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Low Rate (low + rate)
Kinds of Low Rate Selected AbstractsCesarean Delivery in Native American Women: Are Low Rates Explained by Practices Common to the Indian Health Service?BIRTH, Issue 3 2005Sheila F. Mahoney CNM ABSTRACT:,Background: Studying populations with low cesarean delivery rates can identify strategies for reducing unnecessary cesareans in other patient populations. Native American women have among the lowest cesarean delivery rates of all United States populations, yet few studies have focused on Native Americans. The study purpose was to determine the rate and risk factors for cesarean delivery in a Native American population. Methods: We used a case-control design nested within a cohort of Native American live births, , 35 weeks of gestation (n = 789), occurring at an Indian Health Service hospital during 1996,1999. Data were abstracted from the labor and delivery logbook, the hospital's primary source of birth certificate data. Univariate and multivariate analyses examined demographic, prenatal, obstetric, intrapartum, and fetal factors associated with cesarean versus vaginal delivery. Results: The total cesarean rate was 9.6 percent (95% CI 7.2,12.0). Nulliparity, a medical diagnosis, malpresentation, induction, labor length > 12.1 hours, arrested labor, fetal distress, meconium, and gestations < 37 weeks were each significantly associated with cesarean delivery in unadjusted analyses. The final multivariate model included a significant interaction between induction and arrested labor (p < 0.001); the effect of arrested labor was far greater among induced (OR 161.9) than noninduced (OR 6.0) labors. Other factors significantly associated with cesarean delivery in the final logistic model were an obstetrician labor attendant (OR 2.4; p = 0.02) and presence of meconium (OR 2.3; p = 0.03). Conclusions: Despite a higher prevalence of medical risk factors for cesarean delivery, the rate at this hospital was well below New Mexico (16.4%, all races) and national (21.2%, all races) cesarean rates for 1998. Medical and practice-related factors were the only observed independent correlates of cesarean delivery. Implementation of institutional and practitioner policies common to the Indian Health Service may reduce cesarean deliveries in other populations. [source] Low rate of oral human papillomavirus (HPV) infection in women screened for cervical HPV infection in Southern Italy: A cross-sectional study of 140 immunocompetent subjectsJOURNAL OF MEDICAL VIROLOGY, Issue 8 2009Nicoletta Termine Abstract Even though the natural history of cervical and oral human papillomavirus (HPV) infection has been investigated intensely, the possibility that HPV may infect both sites in the same subject is not well documented. This study investigated the frequency of concurrent oral and cervical HPV infection in southern Italian women, in the light of some selected socio-behavioral variables. One hundred forty women (mean age: 36 years), with known cervical HPV status, were analyzed for oral HPV. Age, smoking/drinking habits, clinical and socio-behavioral history were assessed by personal interviews. Oral mucosal cells were collected by oral brushing and HPV DNA was sought by the use of nested PCR amplification followed by direct DNA sequencing and the commercial assay INNOLiPA HPV Genotyping (Innogenetics N.V., Ghent, Belgium). The data were analyzed by using the chi-square test and a logistic regression (logit) model (P,<,0.05 statistically significant). Oral HPV infection was detected in 2/140 (1.4%) cases, being present in 2/76 (2.6%) women with cervical HPV infection and 0/64 uninfected women (P,=,0.19). A lack of type-specific concordance in the two patients with concurrent infection was observed. In the sample of population examined, HPV cervical infection does not seem to predispose to oral transmission, even in the presence of oral,genital sexual habits, thus suggesting the independence of infection at the two mucosal sites. J. Med. Virol. 81:1438,1443, 2009. © 2009 Wiley-Liss, Inc. [source] Extended treatment of older cigarette smokersADDICTION, Issue 6 2009Sharon M. Hall ABSTRACT Aims Tobacco dependence treatments achieve abstinence rates of 25,30% at 1 year. Low rates may reflect failure to conceptualize tobacco dependence as a chronic disorder. The aims of the present study were to determine the efficacy of extended cognitive behavioral and pharmacological interventions in smokers , 50 years of age, and to determine if gender differences in efficacy existed. Design Open randomized clinical trial. Setting A free-standing, smoking treatment research clinic. Participants A total of 402 smokers of , 10 cigarettes per day, all 50 years of age or older. Intervention Participants completed a 12-week treatment that included group counseling, nicotine replacement therapy (NRT) and bupropion. Participants, independent of smoking status, were then assigned randomly to follow-up conditions: (i) standard treatment (ST; no further treatment); (ii) extended NRT (E-NRT; 40 weeks of nicotine gum availability); (iii) extended cognitive behavioral therapy (E-CBT; 11 cognitive behavioral sessions over a 40-week period); or (iv) E-CBT plus E-NRT (E-combined; 11 cognitive behavioral sessions plus 40 weeks nicotine gum availability). Measurements Primary outcome variable was 7-day point prevalence cigarette abstinence verified biochemically at weeks 24, 52, 64 and 104. Findings The most clinically important findings were significant main effects for treatment condition, time and the treatment × time interaction. The E-CBT condition produced high cigarette abstinence rates that were maintained throughout the 2-year study period [(week 24 (58%), 52 (55%), 64 (55%) and 104 (55%)], and was significantly more effective than E-NRT and ST across that period. No other treatment condition was significantly different to ST. No effects for gender were found. Conclusions Extended cognitive behavioral treatments can produce high and stable cigarette abstinence rates for both men and women. NRT does not add to the efficacy of extended CBT, and may hamper its efficacy. Research is needed to determine if these results can be replicated in a sample with a greater range of ages, and improved upon with the addition of medications other than NRT. [source] Prevalence of Constipation Symptoms in Fecally Incontinent Nursing Home ResidentsJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2009John F. Schnelle PhD OBJECTIVES: To determine the prevalence of constipation symptoms and the effects of a brief toileting assistance trial on constipation in a sample of fecally incontinent nursing home (NH) residents. DESIGN: Observational study. SETTING: Five NHs. PARTICIPANTS: One hundred eleven fecally incontinent NH residents. MEASURES: Research staff measured bowel movement frequency every 2 hours for 10 days. The following week, residents were offered toileting assistance every 2 hours for 2 days to determine resident straining, time required for a bowel movement, and resident perceptions of feeling empty after a bowel movement. Constipation data were abstracted from the medical record. RESULTS: The frequency of bowel movements during usual NH care was low (mean=0.32 per person per day), and most episodes were incontinent. The frequency of bowel movements increased significantly, to 0.82 per person per day, and most episodes were continent during the 2 days that research staff provided toileting assistance. Eleven percent of residents showed evidence of straining, and 21% of the time after a continent bowel movement, residents reported not feeling empty. Five percent of participants had medical record or Minimum Data Set documentation indicative of constipation symptoms. CONCLUSION: Low rates of bowel movements during the day that are potentially indicative of constipation were immediately improved during a 2-day trial of toileting assistance in approximately 68% of the residents, although other symptoms of constipation remained in a subset of residents who increased toileting frequency. [source] Secular changes in the quality of published randomized clinical trials in rheumatologyARTHRITIS & RHEUMATISM, Issue 3 2002Catherine L. Hill Objective To assess the quality of published randomized clinical trials (RCTs) in rheumatology and to determine whether there has been improvement in quality between 2 time periods, 1987,1988 and 1997,1998. Methods Using MEDLINE and a hand search of selected rheumatology journals, we identified RCTs of adult rheumatic diseases published in English in 1987,1988 or 1997,1998. We examined trial quality with an expanded version of the Jadad scale, which assesses the adequacy of reported random sequence generation, allocation concealment, blinding, and analysis. All trials were read by 1 reviewer, with prior standardization using a random sample read by 2 reviewers. We also evaluated "high"- versus "low"-impact journals based on citation index. Results Two hundred forty RCTs (1987,1988 119 RCTs, 1997,1998 121 RCTs) were assessed. Results showed improvement in the quality of the trials, but the rates of reported random sequence generation, allocation concealment, power, and intent-to-treat analyses were persistently low. Low rates of reports of random sequence generation, allocation concealment, and intent-to-treat analyses were present even in the high-impact journals. Conclusion There has been improvement in the quality of reporting of RCTs in rheumatology between 1987,1988 and 1997,1998. However, methodologic problems such as lack of allocation concealment, inadequate random sequence generation, lack of reporting of power, and lack of intent-to-treat analyses remain common. Many of these problems are established sources of bias in RCTs and are easily rectifiable. [source] Low rates of colorectal, cervical, and breast cancer screening in Asian Americans compared with non-Hispanic whitesCANCER, Issue 1 2006Cultural influences or access to care? Abstract BACKGROUND Asian Americans have lower cancer screening rates compared with non-Hispanic whites (NHWs). Little is known about mechanisms that underlie disparities in cancer screening. The objectives of the current study were 1) to determine the relation between nativity, years in the United States, language, and cancer screening in NHWs and Asian Americans, independent of access to care and 2) to determine whether Asians reported different reasons than NHWs for not obtaining cancer screening. METHODS This population-based study included 36,660 NHWs, 1298 Chinese, 944 Filipinos, 803 Koreans, 857 Vietnamese, and 1036 Other Asians from the 2001 California Health Interview Survey. The main study outcomes were 1) self-reported colorectal, cervical, and breast cancer screening and 2) reasons for not obtaining cancer screening. RESULTS After adjusting for access to care, several Asian subgroups still had significantly lower rates of all types of cancer screening compared with NHWs. Adjusting for nativity, years in the United States, and English language attenuated the relation between Asian ethnicity and lower rates of colorectal and breast cancer screening. When they were asked what the most important reason was for not having each screening test, foreign-born Asians were significantly more likely than United States-born NHWs to report that they "didn't have problems/symptoms" (P<.01). CONCLUSIONS Nativity, years in the United States, and English language may be markers of cultural differences that are mediating cancer screening disparities. Foreign-born Asians may believe that cancer screening is in response to symptoms rather than tests that are used prior to the development of symptoms. Health education messages must consider how to communicate effectively that "cancer screening is valuable, because it finds cancer before it is advanced enough to cause symptoms." Cancer 2006. © 2006 American Cancer Society. [source] Microcystic Adnexal Carcinoma Involving a Large Portion of the Face: When Is Surgery Not Reasonable?DERMATOLOGIC SURGERY, Issue 11 2005Daniel Brian Eisen MD Background. We report a case of microcystic adnexal carcinoma (MAC) involving a large portion of the face, one of the largest of any MAC reported thus far in this area, and review the literature regarding the nature of the tumor and available treatments. We also review all of the reported cases of metastases and the possible role of radiation in the etiopathogenesis of this tumor. Objective. To review the literature about what is known about therapy for MAC and what options are available to patients who have this disease. Materials and Methods. Case report and review of the literature. Results. Of the 274 cases of MAC thus far reported, there are 6 cases of metastases, only 1 of which resulted in death. Conclusion. Mohs surgery should be the treatment of choice for this tumor; however, when extirpation entails sufficiently large morbidity, given the low rate of metastases and mortality, observation is a reasonable alternative. DANIEL BRIAN EISEN, MD, AND DAVID ZLOTY, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source] Late Inguinal Metastasis of a Well-Differentiated Subungual Squamous Cell Carcinoma after Radical Toe AmputationDERMATOLOGIC SURGERY, Issue 7 2005Kuo-Chin Huang MD Background Although squamous cell carcinoma (SCC) is commonly found on sun-exposed skin, this malignancy in nail beds is rare. There is a very low rate of metastases, especially for well-differentiated lesions without bony involvement. Objective To present a case of late inguinal metastasis after radical toe amputation 3 years previously for subungual SCC. Materials and Methods Case report. Results The patient received modified inguinal lymphadenectomy and adjuvant radiation therapy. No recurrence or metastases were observed for 12 months. Conclusion For patients with subungual SCC postsurgery, it is important to regularly evaluate for a minimum of 3 years, despite the very low rate of metastases. [source] Electrosurgery, Pacemakers and ICDs: A Survey of Precautions and Complications Experienced by Cutaneous SurgeonsDERMATOLOGIC SURGERY, Issue 4 2001Hazem M. El-Gamal MD Background. Minimal information is available in the literature regarding the precautions implemented or complications experienced by cutaneous surgeons when electrosurgery is used in patients with pacemakers or implantable cardioverter-defibrillators (ICDs). The literature pertinent to dermatologists is primarily based on experiences of other surgical specialties and a generally recommended thorough perioperative evaluation. Objective. To determine what precautions are currently taken by cutaneous surgeons in patients with pacemakers or ICDs, and what types of complications have occurred due to electrosurgery in a dermatologic setting. Methods. In the winter of 2000, a survey was mailed to 419 U.S.-based members of the American College of Mohs Micrographic Surgery and Cutaneous Oncology (ACMMSCO). Results. A total of 166 (40%) surveys were returned. Routine precautions included utilizing short bursts of less than 5 seconds (71%), use of minimal power (61%), and avoiding use around the pacemaker or ICD (57%). The types of interference reported were skipped beats (eight patients), reprogramming of a pacemaker (six patients), firing of an ICD (four patients), asystole (three patients), bradycardia (two patients), depleted battery life of a pacemaker (one patient), and an unspecified tachyarrhythmia (one patient). Overall there was a low rate of complications (0.8 cases/100 years of surgical practice), with no reported significant morbidity or mortality. Bipolar forceps were utilized by 19% of respondents and were not associated with any incidences of interference. Conclusions. Significant interference to pacemakers or ICDs rarely results from office-based electrosurgery. No clear community practice standards regarding precautions was evident from this survey. The use of bipolar forceps or true electrocautery are the better options when electrosurgey is required. These two modalities may necessitate fewer perioperative precautions than generally recommended, without compromising patient safety. [source] Side-to-side stapled intra-thoracic esophagogastric anastomosis reduces the incidence of leaks and stenosisDISEASES OF THE ESOPHAGUS, Issue 1 2008D. J. Raz SUMMARY. Trans-hiatal esophagectomy with a hand-sewn anastomosis was for 2 decades the preferred approach in our institution for patients with esophageal cancer. In our experience, this anastomotic technique was associated with a 12% leak rate and a 48% rate of stricture requiring dilatation. We sought to determine if a side-to-side intra-thoracic anastomosis was associated with a lower rate of anastomotic stricture and leak. Thirty-three consecutive patients with distal esophageal cancer or Barrett's esophagus with high grade dysplasia underwent a trans-thoracic esophagectomy with a side-to-side stapled intra-thoracic anastomosis. The overall morbidity was 27%, with no anastomotic stricture or leaks. One patient died (3%). The median time to the resumption of an oral diet was 7 days (range 5,28), and the median length of stay in hospital was 9 days (range 6,45). Trans-thoracic esophagectomy with a side-to-side stapled anastomosis is safe and it is associated with a very low rate of anastomotic complications. We consider this to be the procedure of choice for patients with distal esophageal cancers. [source] Colon interposition in the treatment of esophageal caustic strictures: 40 years of experienceDISEASES OF THE ESOPHAGUS, Issue 6 2007J. Ð. Knez SUMMARY., The objective of this article was to analyze 40 years of experience of colon interposition in the surgical treatment of caustic esophageal strictures from the standpoints of our long-term personal experience. Colon interposition has proved to be the most suitable type of reconstruction for esophageal corrosive strictures. The choice of colon graft is based on the pattern of blood supply, while the type of anastomosis is determined by the stricture level and the part of colon used for reconstruction. In the period between 1964 and 2004, colon interposition was performed in 336 patients with a corrosively scared esophagus, using the left colon in 76.78% of the patients. In 87.5% a colon interposition was performed, while in the remaining patients an additional esophagectomy with colon interposition had to be done. Hypopharyngeal strictures were present in 24.10% of the patients. Long-term follow-up results were obtained in the period between 1 to up to 30 years. Early postoperative complications occurred in 26.48% of patients, among which anastomosic leakage was the most common. The operative mortality rate was 4.16% and late postoperative complications were present in 13.99% of the patients. A long-term follow up obtained in 84.82% of the patients found excellent functional results in 75.89% of them. We conclude that a colon graft is an excellent esophageal substitute for patients with esophageal corrosive strictures, and when used by experienced surgical teams it provides a low rate of postoperative morbidity and mortality, and long-term good and functional quality of life. [source] Overbank deposition along the concave side of the Red River meanders, Manitoba, and its geomorphic significanceEARTH SURFACE PROCESSES AND LANDFORMS, Issue 13 2005Gregory R. Brooks Abstract Slow earth sliding is pervasive along the concave side of Red River meanders that impinge on Lake Agassiz glaciolacustrine deposits. These failures form elongated, low-angled (c. 6 to 10°) landslide zones along the valleysides. Silty overbank deposits that accumulated during the 1999 spring freshet extend continuously along the landslide zones over hundreds of metres and aggraded the lower slopes over a distance 50 to 80 m from the channel margin. The aggradation is not obviously related to meander curvature or location within a meander. Along seven slope profiles surveyed in 1999 near Letellier, Manitoba, the deposits locally are up to 21 cm thick and generally thin with increasing distance from, and height above, the river. Local deposit thickness relates to distance from the channel, duration of inundation of the landslide surface, mesotopography, and variations in vegetation cover. Immediately adjacent to the river, accumulated overbank deposits are up to 4 m thick. The 1999 overbank deposits also were present along the moderately sloped (c. 23 to 27°) concave banks eroding into the floodplain, but the deposits are thinner (locally up to c. 7 cm thick) and cover a narrower area (10 to 30 m wide) than the deposits within the landslide zones. Concave overbank deposition is part of a sediment reworking process that consists of overbank aggradation on the landslide zones, subsequent gradual downslope displacement from earth sliding, and eventually reworking by the river at the toe of the landslide. The presence of the deposits dampens the outward migration of the meanders and contributes to a low rate of contemporary lateral channel migration. Concave overbank sedimentation occurs along most Red River meanders between at least Emerson and St. Adolphe, Manitoba. © Her Majesty the Queen in right of Canada. [source] Arsenite induces delayed mutagenesis and transformation in human osteosarcoma cells at extremely low concentrationsENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 5 2003Kanae Mure Abstract Arsenite is a human multisite carcinogen, but its mechanism of action is not known. We recently found that extremely low concentrations (,0.1 ,M) of arsenite transform human osteosarcoma TE85 (HOS) cells to anchorage-independence. In contrast to other carcinogens which transform these cells within days of exposure, almost 8 weeks of arsenite exposure are required for transformation. We decided to reexamine the question of arsenite mutagenicity using chronic exposure in a spontaneous mutagenesis assay we previously developed. Arsenite was able to cause a delayed increase in mutagenesis at extremely low concentrations (,0.1 ,M) in a dose-dependent manner. The increase in mutant frequency occurred after almost 20 generations of growth in arsenite. Transformation required more than 30 generations of continuous exposure. We also found that arsenite induced gene amplification of the dihydrofolate reductase (DHFR) gene in a dose-dependent manner. Since HOS cells are able to methylate arsenite at a very low rate, it was possible that active metabolites such as monomethylarsonous acid (MMAIII) contributed to the delayed mutagenesis and transformation in these cells. However, when the assay was repeated with MMAIII, we found no significant increase in mutagenesis or transformation, suggesting that arsenite-induced delayed mutagenesis and transformation are not caused by arsenite's metabolites, but by arsenite itself. Our results suggest that long-term exposure to low concentrations of arsenite may affect signaling pathways that result in a progressive genomic instability. Environ. Mol. Mutagen. 41:322,331, 2003. © 2003 Wiley-Liss, Inc. [source] Toxicokinetics of polycyclic aromatic hydrocarbons in Eisenia andrei (Oligochaeta) using spiked soilENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2000Tjalling Jager Abstract The accumulation of four polycyclic aromatic hydrocarbons ([PAHs]; phenanthrene, pyrene, fluoranthene, and ben-zo[a]pyrene) was tested in the earthworm Eisenia andrei in a spiked artificial soil medium. A typical peak in the body residues was observed for all PAHs around day 7, which could not be explained from changes in the total soil concentration. It is argued that the most likely cause of this peak is a decrease in the concentration in pore water, the main bioavailable phase for earthworms. This decrease is caused by biodegradation while the low rate of mass transfer from the solid state precludes replenishment. To describe the data, bioavailability was assumed to decline exponentially in time, but the shape of the accumulation curves suggests a more abrupt change. Estimates of the uptake rate (k1) are similar for all PAHs when expressed on soil solution basis (approximately 2,000 L/kg/d); the elimination rate (k2) shows a decrease with Kow as expected, but the values tend to be slightly lower than literature data. The dynamic bioconcentration factors (k1/k2) agree well with an equilibrium partitioning between soil water and the phases inside the organism. [source] MULTIVARIATE QUANTITATIVE GENETICS AND THE LEK PARADOX: GENETIC VARIANCE IN MALE SEXUALLY SELECTED TRAITS OF DROSOPHILA SERRATA UNDER FIELD CONDITIONSEVOLUTION, Issue 12 2004Emma Hine Abstract Single male sexually selected traits have been found to exhibit substantial genetic variance, even though natural and sexual selection are predicted to deplete genetic variance in these traits. We tested whether genetic variance in multiple male display traits of Drosophila serrata was maintained under field conditions. A breeding design involving 300 field-reared males and their laboratory-reared offspring allowed the estimation of the genetic variance-covariance matrix for six male cuticular hydrocarbons (CHCs) under field conditions. Despite individual CHCs displaying substantial genetic variance under field conditions, the vast majority of genetic variance in CHCs was not closely associated with the direction of sexual selection measured on field phenotypes. Relative concentrations of three CHCs correlated positively with body size in the field, but not under laboratory conditions, suggesting condition-dependent expression of CHCs under field conditions. Therefore condition dependence may not maintain genetic variance in preferred combinations of male CHCs under field conditions, suggesting that the large mutational target supplied by the evolution of condition dependence may not provide a solution to the lek paradox in this species. Sustained sexual selection may be adequate to deplete genetic variance in the direction of selection, perhaps as a consequence of the low rate of favorable mutations expected in multiple trait systems. [source] FROM MICRO- TO MACROEVOLUTION THROUGH QUANTITATIVE GENETIC VARIATION: POSITIVE EVIDENCE FROM FIELD CRICKETSEVOLUTION, Issue 10 2004Mattieu Bégin Abstract . -Quantitative genetics has been introduced to evolutionary biologists with the suggestion that microevolution could be directly linked to macroevolutionary patterns using, among other parameters, the additive genetic variance/ covariance matrix (G) which is a statistical representation of genetic constraints to evolution. However, little is known concerning the rate and pattern of evolution of G in nature, and it is uncertain whether the constraining effect of G is important over evolutionary time scales. To address these issues, seven species of field crickets from the genera Gryllus and Teleogryllus were reared in the laboratory, and quantitative genetic parameters for morphological traits were estimated from each of them using a nested full-sibling family design. We used three statistical approaches (T method, Flury hierarchy, and Mantel test) to compare G matrices or genetic correlation matrices in a phylogenetic framework. Results showed that G matrices were generally similar across species, with occasional differences between some species. We suggest that G has evolved at a low rate, a conclusion strengthened by the consideration that part of the observed across-species variation in G can be explained by the effect of a genotype by environment interaction. The observed pattern of G matrix variation between species could not be predicted by either morphological trait values or phylogeny. The constraint hypothesis was tested by comparing the multivariate orientation of the reconstructed ancestral G matrix to the orientation of the across-species divergence matrix (D matrix, based on mean trait values). The D matrix mainly revealed divergence in size and, to a much smaller extent, in a shape component related to the ovipositor length. This pattern of species divergence was found to be predictable from the ancestral G matrix in agreement with the expectation of the constraint hypothesis. Overall, these results suggest that the G matrix seems to have an influence on species divergence, and that macroevolution can be predicted, at least qualitatively, from quantitative genetic theory. Alternative explanations are discussed. [source] Isoprenoid biosynthesis in plants , 2C -methyl- d -erythritol-4-phosphate synthase (IspC protein) of Arabidopsis thalianaFEBS JOURNAL, Issue 19 2006Felix Rohdich The ispC gene of Arabidopsis thaliana was expressed in pseudomature form without the putative plastid-targeting sequence in a recombinant Escherichia coli strain. The recombinant protein was purified by affinity chromatography and was shown to catalyze the formation of 2C -methyl- d -erythritol 4-phosphate from 1-deoxy- d -xylulose 5-phosphate at a rate of 5.6 µmol·min,1·mg,1 (kcat 4.4 s,1). The Michaelis constants for 1-deoxy- d -xylulose 5-phosphate and the cosubstrate NADPH are 132 and 30 µm, respectively. The enzyme has an absolute requirement for divalent metal ions, preferably Mn2+ and Mg2+, and is inhibited by fosmidomycin with a Ki of 85 nm. The pH optimum is 8.0. NADH can substitute for NADPH, albeit at a low rate (14% as compared to NADPH). The enzyme catalyzes the reverse reaction at a rate of 2.1 µmol·min -1·mg -1. [source] Reduced fertility of mouse epididymal sperm lacking Prss21/Tesp5 is rescued by sperm exposure to uterine microenvironmentGENES TO CELLS, Issue 10 2008Misuzu Yamashita Although the acrosome reaction and subsequent penetration of sperm through the egg zona pellucida (ZP) are essential for mammalian fertilization, the molecular mechanism is still controversial. We have previously identified serine protease Tesp5 identical to Prss21 on the mouse sperm surface as a candidate enzyme involved in sperm penetration through the ZP. Here we show that despite normal fertility of male mice lacking Prss21/Tesp5, the epididymal sperm penetrates the ZP only at a very low rate in vitro, presumably owing to the reduced ability to bind the ZP and undergo the ZP-induced acrosome reaction. The ability of Prss21-null sperm to fuse with the egg in vitro was also impaired severely. Intriguingly, the reduced fertility of Prss21-null epididymal sperm was rescued by exposure of the sperm to the uterine microenvironment and by in vitro treatment of the sperm with uterine fluids. These data suggest the physiological importance of sperm transport through the uterus. [source] Pristine New Zealand forest soil is a strong methane sinkGLOBAL CHANGE BIOLOGY, Issue 1 2004Sally J. Price Abstract Methanotrophic bacteria oxidize methane (CH4) in forest soils that cover ,30% of Earth's land surface. The first measurements for a pristine Southern Hemisphere forest are reported here. Soil CH4 oxidation rate averaged 10.5±0.6 kg CH4 ha,1 yr,1, with the greatest rates in dry warm soil (up to 17 kg CH4 ha,1 yr,1). Methanotrophic activity was concentrated beneath the organic horizon at 50,100 mm depth. Water content was the principal regulator of (r2=0.88) from the most common value of field capacity to less than half of this when the soil was driest. Multiple linear regression analysis showed that soil temperature was not very influential. However, inverse co-variability confounded the separation of soil water and temperature effects in situ. Fick's law explained the role of water content in regulating gas diffusion and substrate supply to the methanotrophs and the importance of pore size distribution and tortuosity. This analysis also showed that the chambers used in the study did not affect the oxidation rate measurements. The soil was always a net sink for atmospheric CH4 and no net CH4 (or nitrous oxide, N2O) emissions were measured over the 17-month long study. For New Zealand, national-scale extrapolation of our data suggested the potential to offset 13% of CH4 emissions from ca. 90 M ruminant animals. Our average was about 6.5 times higher than rates reported for most Northern Hemisphere forest soils. This very high was attributed to the lack of anthropogenic disturbance for at least 3000,5000 years and the low rate of atmospheric nitrogen deposition. Our truly baseline data could represent a valid preagricultural, preindustrial estimate of the soil sink for temperate latitudes. [source] Water Resource Implications of 18O and 2H Distributions in a Basalt Aquifer SystemGROUND WATER, Issue 6 2000Kathryn R. Larson Ongoing decline of water levels in the confined basalt aquifers of the Pullman-Moscow Basin of Washington and Idaho has prompted study of the timing, amount and distribution of recharge to the system. Previous radiocarbon ages indicate residence times on the order of 103 years and greater and suggest a low rate of recharge to the lower basalt aquifer since the end of Pleistocene time. By contrast, more recent hydrodynamic flow modeling studies invoke a larger Holocene recharge rate through the unconfined loess unit to the upper and lower basalt aquifers, which implies relatively short residence times (102 years). Stable isotopes were used to independently assess contrasting recharge models by comparing 18O/16O and D/H ratios of late-Holocene shallow ground water and deep ground water. Linear regression of local precipitation ratios yields ,D = 6.9 ,18O ,18.5. There is no evidence of fractionation of ground water ratios by recharge processes or water-rock interactions. Deep basalt ground water ,18O values are depleted by 0.4 to 4.9 per mil relative to shallow, recently recharged ground waters and have ,18O values statistically distinct from waters sampled from other stratigraphic units. These findings suggest that the deep waters in the basin were not precipitated under current climate conditions and that aquifer recharge rates to the deep basalt aquifer are substantially lower than have been recently estimated. This in turn suggests that a sustainable ground water exploitation scheme must reduce reliance on the deep ground water resource. [source] Hepatitis C virus quasispecies in the natural course of HCV-related disease in patients with haemophiliaHAEMOPHILIA, Issue 1 2004G. Tagariello Summary., Patients with haemophilia show high prevalence of hepatitis C infection but low rate of progressive liver disease when they are not co-infected with HIV. The balance between host immune system and hepatitis C virus (HCV) variability seems to play a major role in the evolution of the HCV-related disease. To address this point we have studied, in a group of selected patients with haemophilia, the composition and in some cases the evolution, of the highest variable envelope gene within the hypervariable region 1 (HVR1) of the HCV, which is the region more directly exposed to the host immune response. Five of 12 patients show a very high homogeneity of the HVR1 and four of those had severe progressive liver disease. These results seem to confirm the major role of the immunity in driving the variability of the HCV rather than the high degree of different HCV strains to which haemophiliacs have been in touch with, during their long-term replacement therapy. Our results seem in keeping with other studies on different type of patients, where a low degree of quasispecies variability has been demonstrated in relationship with the progression and the severity of their liver disease. [source] Thirty-day Outcomes of Emergency Department Patients Undergoing Electrical Cardioversion for Atrial Fibrillation or FlutterACADEMIC EMERGENCY MEDICINE, Issue 4 2010Frank Xavier Scheuermeyer MD Abstract Objectives:, While the short-term (<7-day) safety and efficiency of electrical cardioversion for emergency department (ED) patients with atrial fibrillation or flutter have been established, the 30-day outcomes with respect to stroke, thromboembolic events, or death have not been investigated. Methods:, A two-center cohort of consecutive ED patients undergoing cardioversion for atrial fibrillation or flutter between January 1, 2000, and September 30, 2007, was retrospectively investigated. This cohort was probabilistically linked with both a regional ED database and the provincial health registry to determine which patients had a subsequent ED visit or hospital admission, stroke, or thromboembolic event or died within 30 days. In addition, trained reviewers performed a detailed chart abstraction on 150 randomly selected patients, with emphasis on demographics, vital signs, medical treatment, and predefined adverse events. Hemodynamically unstable patients or those whose condition was the result of an underlying acute medical diagnosis were excluded. Data were analyzed by descriptive methods. Results:, During the study period, 1,233 patients made 1,820 visits for atrial fibrillation or flutter to the ED. Of the 400 eligible patients undergoing direct-current cardioversion (DCCV), no patients died, had a stroke, or had a thromboembolic event in the following 30 days (95% confidence interval [CI] = 0.0 to 0.8% for all outcomes). A total of 141 patients were included in the formal chart review, with five patients (3.5%, 95% CI = 0.5% to 6.6%) failing cardioversion, six patients (4.3%, 95% CI = 0.9% to 7.6%) having a minor adverse event that did not change disposition, and five patients (3.5%, 95% CI = 0.5% to 6.6%) admitted to hospital at the index visit. Conclusions:, Cardioversion of patients with atrial fibrillation or flutter in the ED appears to have a very low rate of long-term complications. ACADEMIC EMERGENCY MEDICINE 2010; 17:408,415 © 2010 by the Society for Academic Emergency Medicine [source] Long-term follow-up of nevirapine-treated patients in a single-centre cohortHIV MEDICINE, Issue 8 2009M Colafigli Objectives We reviewed the safety and efficacy of nevirapine (NVP)-based therapy in all patients initiating NVP-containing combined antiretroviral therapy [cART (,3 drugs)] in our clinic since 1994. Methods Patient characteristics and laboratory values from the start of the NVP-based cART regimen to the last available follow-up or to NVP discontinuation were retrieved from an observational database. Results Five hundred and seventy-three patients were treated with NVP-based cART for a median of 18.4 (range 0.1,128.8) months. The 1-year cumulative estimated probability of discontinuing NVP-containing regimens for toxicity was 0.203. Only 1.9% developed a grade 3 alanine aminotransferase (ALT) elevation. Significant increases in high-density lipoprotein cholesterol were observed up to month 12 except in treatment-naïve patients, where the increase was limited to 3 months. Discontinuation because of cutaneous reaction was predicted independently by female gender [Hazard Ratio (HR) 3.21, P<0.001] and Centers for Disease Control class C (HR 0.50, P=0.012). Discontinuation because of liver toxicity was predicted independently by anti-hepatitis C virus positivity (HR 3.84, P<0.001). In patients starting NVP-containing cART with undetectable viral loads, the 5-year estimated probability of viral load >400 HIV-1 RNA copies/mL was 0.34. Conclusions Long-term follow-up with an NVP-containing cART showed a low rate of discontinuation caused by liver toxicity and the maintenance of virological suppression in patients switched with undetectable viral loads. [source] Utility of the Gyrus open forceps in hepatic parenchymal transectionHPB, Issue 3 2009Matthew R. Porembka Abstract Objective:, This study aimed to evaluate if the Gyrus open forceps is a safe and efficient tool for hepatic parenchymal transection. Background:, Blood loss during hepatic transection remains a significant risk factor for morbidity and mortality associated with liver surgery. Various electrosurgical devices have been engineered to reduce blood loss. The Gyrus open forceps is a bipolar cautery device which has recently been introduced into hepatic surgery. Methods:, We conducted a single-institution, retrospective review of all liver resections performed from November 2005 through November 2007. Patients undergoing resection of at least two liver segments where the Gyrus was the primary method of transection were included. Patient charts were reviewed; clinicopathological data were collected. Results:, Of the 215 open liver resections performed during the study period, 47 patients met the inclusion criteria. Mean patient age was 61 years; 34% were female. The majority required resection for malignant disease (94%); frequent indications included colorectal metastasis (66%), hepatocellular carcinoma (6%) and cholangiocarcinoma (4%). Right hemihepatectomy (49%), left hemihepatectomy (13%) and right trisectionectomy (13%) were the most frequently performed procedures. A total of 26 patients (55%) underwent a major ancillary procedure concurrently. There were no operative mortalities. Median operative time was 220 min (range 97,398 min). Inflow occlusion was required in nine patients (19%) for a median time of 12 min (range 3,30 min). Median total estimated blood loss was 400 ml (range 10,2000 ml) and 10 patients (21%) required perioperative transfusion. All patients had macroscopically negative margins. Median length of stay was 8 days. Two patients (4%) had clinically significant bile leak. The 30-day postoperative mortality was zero. Conclusions:, Use of the Gyrus open forceps appears to be a safe and efficient manner of hepatic parenchymal transection which allows rapid transection with acceptable blood loss, a low rate of perioperative transfusion, and minimal postoperative bile leak. [source] Current modalities and new advances in the treatment of basal cell carcinomaINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 5 2006Roger I. Ceilley MD Basal cell carcinoma (BCC) is one of the most common cancers. Surgical extirpation is currently the standard of care for BCC, which is associated with several advantages and disadvantages. Procedures such as surgical excision used to treat superficial BCC (sBCC) and nodular BCC (nBCC) may have high 5-year recurrence rates if tumors are not completely excised. Curettage with electrodesiccation is a common method for treating primary BCC. However, multiple cycles are recommended and the procedure can have unsatisfactory cosmetic results (e.g. scarring and hypopigmentation). Mohs micrographic surgery has a low rate of disease recurrence but is a specialized procedure usually limited to specific indications (e.g. high-risk tumors). Cryosurgery and photodynamic therapy require multiple cycles and are associated with variable cosmetic outcomes and recurrence rates. As with any procedure, potential risks and patient quality-of-life issues need to be considered. In addition, substantial patient and healthcare provider inconvenience limit the practical utility of some modalities. Pharmacologic interventions provide another treatment option as adjunctive or monotherapy. Investigations of imiquimod, a novel immune response modifier, have indicated that this topical, noninvasive agent is safe and well tolerated and may be efficacious in the treatment of BCC. This review will highlight the role of standard treatment modalities and introduce new advances in the treatment of BCC. [source] Predictors of rehospitalization after total weight recovery in adolescents with anorexia nervosaINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 1 2004Josefina Castro Abstract Objective The current study analyzed the variables related to rehospitalization after total weight recovery in adolescents with anorexia nervosa. Method One hundred and one patients first admitted for inpatient treatment, aged 11,19 years, were followed up for 12 months after discharge. Results Twenty-five subjects (24.8%) required readmission after complete weight recovery and 76 (75.2%) did not. Duration of disorder, weight loss, body mass index at first admission, and global body image distortion were similar in the two groups. Patients needing readmission had a lower rate of weight gain (p < .001), a lower mean age (p = .007), a higher mean score on the Eating Attitudes Test (EAT; p = .009), and a higher percentage of hips overestimation (p = .049). In a stepwise logistic regression analysis, these three variables predicted readmission and correctly classified 77.6% of patients. Taken as discrete variables, age younger than 15 years old, EAT score above 55, and a rate of weight gain lower than 150 grams per day were associated with a higher percentage of readmissions. Discussion The variables most clearly related to readmission were young age, abnormal eating attitudes, and a low rate of weight gain. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 22,30, 2004. [source] The STRokE DOC trial technique: ,video clip, drip, and/or ship'INTERNATIONAL JOURNAL OF STROKE, Issue 4 2007B. C. Meyer Rationale To describe the clinical trial methods of a site-independent telemedicine system used in stroke. Aims A lack of readily available stroke expertise may partly explain the low rate of rt-PA use in acute stroke. Although telemedicine systems can reliably augment expertise available to rural settings, and may increase rt-PA use, point-to-point systems do require fixed base stations. Site-independent systems may minimize delay. The STRokE DOC trial assesses whether site-independent telemedicine effectively and efficiently brings rt-PA to a remote population. Design STRokE DOC is a 5-year, 400-participant, noninvasive trial, comparing two consultative techniques at four remote sites. Participants are randomized to acute ,STRokE DOC telemedicine' or ,telephone' consultations. Treatment decision accuracy is adjudicated at two time points, using three levels of data availability and an independent auditor. Study outcomes The primary outcome measure is whether there was a ,correct decision to treat or not to treat using rt-PA' at each of three adjudication levels (primarily at Level #2). Secondary outcomes include the number of thrombolytic recommendations, intracerebral hemorrhage, and 90-day outcomes. Using the STRokE DOC system (or telephone evaluation), medical history, neurologic scales, CT interpretations, and recommendations have been completed on over 200 participants to date. Of the initial 11, nonrandomized, ,run-in' patients, six (65%) were evaluated wirelessly, and five (45%) were evaluated with a site-independent LAN or cable modem. Three (27%) received rt-PA. The adjudication methodology was able to show both agreements and disagreements in these 11 cases. It is feasible to perform site-independent stroke consultations, and adjudicate those cases, using the STRokE DOC system and trial design. Telemedicine efficacy remains to be proven. [source] Clinical, urodynamic and endoscopic characteristics of the Stanford pouch ileal neobladder constructed with absorbable staplesINTERNATIONAL JOURNAL OF UROLOGY, Issue 12 2000M Cemil Uygur Abstract Purpose The clinical, urodynamic and endoscopic aspects of the Stanford pouch ileal neobladder formed with absorbable staples were investigated. Methods A Stanford pouch ileal neobladder was formed using absorbable staples after radical cystoprostatectomy in 30 male patients with the diagnosis of muscle invasive carcinoma of the bladder between 1995 and 1998. The mean age of the patients was 62 (range 41,70) years. Patients were followed with arterial blood gas, serum biochemistry, pouch cystography, urodynamic tests and endoscopy. Results Five (16.7%) patients had early postoperative complications and three were related to the neobladder. One year postoperatively, low grade (I, II) vesicoureteral reflux was present in five (16.7%) cases. The mean preoperative and 6 months postoperative serum creatinine levels were 1.07 ± 0.3 mg/dL and 1.2 ± 0.4 mg/dL, respectively, but the difference was not statistically significant (P = 0.1). Six months postoperatively the mean serum chloride level was 109 ± 4.5 (range 100,113) mmol/L and the mean arterial blood pH was 7.37 ± 0.2 (range 7.3,7.4). Two (6.7%) patients required oral alkaline supplementation because of high chloride levels. All the patients except one were continent throughout the day after 1 year. However, nocturnal enuresis was present in 25 (83.3%) cases. The pouch capacity was increased gradually up to 12 months postoperatively and the mean pouch capacity 12 months postoperatively was 460 ± 95.8 mL. Micturition occurred spontaneously in most patients while some needed abdominal straining. None of the patients had a residual urine of more than 60 mL. The mean maximum flow rate 6 months postoperatively was 9.8 (range 5.4,15.0) mL/s. After 6 months the stapled edge was noticed as a nodular line. One year postoperatively only a white scar could be observed at the suture line. Conclusion The Stanford pouch ileal neobladder constructed using absorbable staples was able to provide a good capacity,low pressure reservoir with a low rate of complications. [source] Global carbonate accumulation rates from Cretaceous to Present and their implications for the carbon cycle modelISLAND ARC, Issue 1 2001T. Nakamori Abstract Global carbonate accumulation rates on the surface of the earth, including not only platforms but also continental margin slopes and deep-sea from the Cretaceous to Present, are estimated by compiling previous geologic studies. These rates are revised, taking account of the erosional effect of the sediments on the platform and deep-sea. Long-term model carbonate fluxes from the ocean to the crust are calculated on the basis of the carbon cycle model (GEOCARB of Berner 1991). The rates based on the actual geologic data indicate much lower values than model fluxes, excluding the Pliocene and Quaternary. The discrepancy could be attributed to the two misunderstandings, namely an overestimate of carbonate accumulation rate for the Quaternary and an incorrect use of the higher Quaternary rate for a boundary condition of the model. The carbonate accumulation rate for the Pliocene to Quaternary is lowered from 29.8 × 1018 mol/Ma (modified from Opdyke & Wilkinson 1988) to 14.8 × 1018 mol/Ma in the present study, assuming that the rate from Quaternary to Pliocene is almost the same as the Miocene value. New model fluxes are recalculated with the new boundary condition in the Quaternary (14.8 × 1018 mol/Ma). Revised model fluxes show general trends of high rates in 120 Ma or 130 Ma, and a low rate in 0 Ma, and are in agreement with the accumulation rate pattern. [source] Tear-film lipid layer morphology and corneal sensation in the development of blinking in neonates and infantsJOURNAL OF ANATOMY, Issue 3 2005John G. Lawrenson Abstract The aim of the study was to evaluate the role of lipid layer thickness and corneal sensation in the development of blinking in neonates. The study group comprised sixty-four neonates and infants (mean age 27.5 ± 15 (sd) weeks, range 3.4,52) whose mothers were attending a general practice healthy baby clinic. Spontaneous eye-blink activity was determined from digital videographic recordings; tear film lipid layer morphology wasexamined using interference patterns produced by the Keeler TearscopeÔ Plus over a five-point grading scale (higher grades are associated with thick and stable lipid films); corneal sensation threshold was assessed with the Non-Contact Corneal Aesthesiometer (NCCA), using the eye-blink response as an objective indication that the cooling stimulus had been felt; palpebral aperture dimensions were measured using calibrated digital still images of the eye in the primary position. The overall mean spontaneous blink-rate was found to be 3.6 (± 0.3) blinks min,1, and the mean interblink time was 21.6 (± 2.8) s. The lowest blink-rates were observed in the 0,17-week age group (average 2 blinks min,1). The blink-rate showed a highly significant correlation with age (r = 0.46, P < 0.01). The overall mean lipid layer grading was 3.6 (± 0.2 SE) arbitrary units. Higher grades were found in the newborn and the mean grading score reduced with age (P < 0.01). The mean sensation threshold to blink (TTB) was 0.69 (0.04 SE) mbar, which did not differ from a control group of older subjects (P > 0.05). There was a rapid increase in palpebral aperture length and width from birth to 1 year old, with surface area increasing by 50% over the same period. We concluded that the low rate of spontaneous eye blink activity in neonates is associated with a thick stable lipid layer that may be a function of a small palpebral aperture. Furthermore, neonates appear to have the capacity to detect ocular surface cooling, which is a major trigger for spontaneous blinking. [source] | ||||||||||||||||||||||||||||||||||||||||||||||