Mississippi River flood of 2008: observations of a large freshwater diversion on physical, chemical, and biological characteristics of a shallow estuarine lake.

High nitrogen (N) loading to coastal aquatic systems can be expressed as increased algal production and subsequent low dissolved oxygen. In April, 2008, predictions for extreme flood stage for the Lower Mississippi River triggered the opening of the Bonnet Carré Spillway, a major release valve for the river. The spillway diverted approximately 8 km3 of water over one month of operation into Lake Pontchartrain with a concomitant 10000 t of NO3-N. Satellite imagery, physical, water quality, and chlorophyll a (chl a) measurements show that the Mississippi River plume mixed with < 40% of the lake during this time, and much of the nutrient load was transported to the coastal ocean. Nitrate, dissolved reactive phosphorus (P), and dissolved silica (Si) concentrations were 4.8, 5.0, and 3.2 times higher, respectively, within the river plume when compared with those of the lake water. Despite the high nutrient concentrations within the river plume, phytoplankton biomass, evidenced by chl a concentrations, was low. Much of the nutrient load appeared to bypass the lake and was transported to the coastal ocean during the opening of the diversion. The potential removal of a total of 7.6% of the N load from the Mississippi River during the one month of flood level flow may have been a contributing factor in the lower than predicted hypoxia zone off the Louisiana coast during the summer of 2008.

Shock wave therapy for lateral elbow pain.

BACKGROUND: This review is one in a series of reviews of interventions for lateral elbow pain. OBJECTIVES: To determine the effectiveness and safety of extracorporeal shock wave therapy (ESWT) for lateral elbow pain. SEARCH STRATEGY: Searches of the Cochrane Controlled Trials Register (Cochrane Library Issue 2, 2004), MEDLINE, EMBASE, CINAHL, and Science Citation Index (SCISEARCH) were conducted in February 2005, unrestricted by date. SELECTION CRITERIA: We included nine trials that randomised 1006 participants to ESWT or placebo and one trial that randomised 93 participants to ESWT or steroid injection. DATA COLLECTION AND ANALYSIS: For each trial two independent reviewers assessed the methodological quality and extracted data. Methodological quality criteria included appropriate randomisation, allocation concealment, blinding, number lost to follow up and intention to treat analysis. Where appropriate, pooled analyses were performed. If there was significant heterogeneity between studies or the data reported did not allow statistical pooling, individual trial results were described in the text. MAIN RESULTS: Eleven of the 13 pooled analyses found no significant benefit of ESWT over placebo. For example, the weighted mean difference for improvement in pain (on a 100-point scale) from baseline to 4-6 weeks from a pooled analysis of three trials (446 participants) was -9.42 (95% CI -20.70 to 1.86) and the weighted mean difference for improvement in pain (on a 100-point scale) provoked by resisted wrist extension (Thomsen test) from baseline to 12 weeks from a pooled analysis of three trials (455 participants) was -9.04 (95% CI -19.37 to 1.28). Two pooled results favoured ESWT. For example, the pooled relative risk of treatment success (at least 50% improvement in pain with resisted wrist extension at 12 weeks) for ESWT in comparison to placebo from a pooled analysis of two trials (192 participants) was 2.2 (95% CI 1.55 to 3.12). However this finding was not supported by the results of four other individual trials that were unable to be pooled. Steroid injection was more effective than ESWT at 3 months after the end of treatment assessed by a reduction of pain of 50% from baseline (21/25 (84%) versus 29/48 (60%), p<0.05). Minimal adverse effects of ESWT were reported. Most commonly these were transient pain, reddening of the skin and nausea and in most cases did not require treatment discontinuation or dosage adjustment. AUTHORS' CONCLUSIONS: Based upon systematic review of nine placebo-controlled trials involving 1006 participants, there is "Platinum" level evidence that shock wave therapy provides little or no benefit in terms of pain and function in lateral elbow pain. There is "Silver" level evidence based upon one trial involving 93 participants that steroid injection may be more effective than ESWT.

Grandma's hands: parental perceptions of the importance of grandparents as secondary caregivers in families of children with disabilities.

This study examines parental perceptions of the importance of grandparents as providers of routine care to children with disabilities and the impact of such assistance on parental well-being. Data are drawn from a survey and follow-up interactive interviews. Findings of the survey indicate that: 1) grandparents are a common source of weekly assistance-significantly more common than other relatives or friends and neighbors; 2) where grandparents participate, the number of other sources of support is also higher; and 3) help from grandparents has a positive, while the number of other sources of help has a negative, relationship to parental ability to maintain a positive emotional outlook and to avoid physical exhaustion. Findings of the interactive interviews suggest that: 1) grandparent participation can promote pride and "normalized attitudes" by helping grandparents to get to know the child with a disability on an intimate basis; 2) when grandparents do not participate, parents may feel the need to manage the information given to and the emotional responses experienced by grandparents who have not had a chance to get know and love the child through frequent, direct contact; and 3) parents are very concerned that if grandparents themselves begin to need help due to increased age and disability, they will not ask for it because of fear that parents are already overburdened by the unusual demands of their parenting roles.

The interrelationship of wind instrument technic, orthodontic treatment, and orofacial myology.

This article identifies, defines and reviews the synergy between orofacial myofunctional and orthodontic health with regard to wind instrument performance, and summarizes the skills involved in playing an instrument. (i.e. embouchure, articulation, breath support.) Criteria and strategies for choosing an instrument are outlined via orthodontic classifications, therapeutic value or contraindication and team approaches. The author concludes that a team-oriented approach on the part of the professions cited in this article are of the ultimate good for the student/patient.

Colonic epithelial cell proliferation in hereditary non-polyposis colorectal cancer.

BACKGROUND: Despite the recent discovery of four genes responsible for up to 90% of all cases of hereditary non-polyposis colorectal cancer (HNPCC), there will still be families in whom predictive testing is not possible. A phenotypic biomarker would therefore be useful. An upwards shift of the proliferative compartment in colonic crypts is reported to be one of the earliest changes in premalignant mucosa. AIMS: To assess the role of crypt cell proliferation as a phenotypic biomarker in HNPCC. PATIENTS: Thirty five patients at 50% risk of carrying the HNPCC gene (21 of whom subsequently underwent predictive testing and hence gene carrier status was known) and 18 controls. METHODS: Crypt cell proliferation was measured at five sites in the colon using two different techniques. Labelling index was determined using the monoclonal antibody MIB1 and whole crypt mitotic index was measured using the microdissection and crypt squash technique. The distribution of proliferating cells within the crypts was also assessed. RESULTS: There were no significant differences in the total labelling index or mean number of mitoses per crypt, nor in the distribution of proliferating cells within the crypt, between the study and control groups at any site. When the 21 patients in whom gene carrier status was known were analysed separately there were no significant differences in the measured indices of proliferation between the HNPCC gene carriers and non-gene carriers. CONCLUSION: Crypt cell proliferation is not a discriminative marker of gene carriage in HNPCC.

Hereditary non-polyposis colorectal cancer.

Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant condition in which affected individuals develop colorectal cancer or extracolonic cancers, most commonly endometrial, at an early age. Recent advances in molecular genetics have led to the identification and sequencing of four genes thought to be responsible for the majority of cases of hereditary non-polyposis colorectal cancer. A description of the disease along with details of the underlying genetics and pathological features are presented. Current management and screening policies in these pedigrees are not clearly established. This article discusses some of the controversies in the light of predictive testing.

Efficacy of an in-feed formulation of ivermectin against somatic larvae of Strongyloides ransomi in pregnant swine.

OBJECTIVE: To confirm that ivermectin fed for 7 days to pregnant sows controls transmission of Strongyloides ransomi larvae to pigs via the colostrum or milk. ANIMALS: 24 mixed-breed sows. PROCEDURE: The sows were infected with 250,000 S ransomi larvae on 3 occasions (days 63, 64, or 65, days 71 or 73, and days 78, 79, or 80 of gestation). Eight sows received ivermectin at a dosage of 100 micrograms of ivermectin/kg of body weight/d from days 92 to 99 of gestation, and 8 sows were treated from days 103 to 110 of gestation; 8 remaining sows received unmedicated vehicle. Numbers of S ransomi larvae were counted in samples of colostrum or milk collected 1, 2, and 7 days after parturition. At 7 and 14 days after parturition, fecal samples were collected from each sow and from 4 pigs from each litter for determination of nematode egg counts; at the latter date, pigs were euthanatized and necropsied for worm counting. RESULTS: Pigs born to ivermectin-treated sows had significantly (P < 0.01) fewer adult S ransomi than did those born to control sows; efficacy was 100%. Treated sows had significantly (P < 0.05) fewer S ransomi larvae in colostrum/milk samples taken 1, 2, and 7 days after parturition than did control sows; efficacy was 100%, with the exception of 1 S ransomi larva found in a milk sample from 1 treated sow at 2 days after parturition. CONCLUSION AND CLINICAL RELEVANCE: Ivermectin fed to sows during the last third of gestation at a dosage of 100 micrograms/kg/d for 7 consecutive days is highly efficacious for control of transmission of infective S ransomi larvae to pigs via colostrum or milk.

Frequency of extra-cardiac activity and its effect on 99Tcm-MIBI cardiac SPET interpretation.

There are limited published data concerning the frequency and relative intensity of abdominal activity on 99Tcm-methoxyisobutyl isonitrile (99Tcm-MIBI) myocardial perfusion scans and its effect on interpretation. We undertook a blinded prospective study to evaluate (1) the frequency and intensity of abdominal activity on single photon emission tomography (SPET) scans, (2) its effect on separate evaluation of rest and stress SPET images, and (3) its effect on clinical interpretation. Patients undergoing one-day rest-stress 99Tcm-MIBI scans were randomized to receive 99Tcm-MIBI obtained from one of two radiopharmacies. The rest plus exercise or rest plus intravenous dipyridamole scans of 303 patients were scored separately by three physicians for (1) intensity of abdominal activity and (2) its effect on scan evaluation. Nuclear reports generated independently of the blinded evaluation were reviewed to assess the effect of abdominal activity on clinical interpretation. There were no statistical differences between pharmacies. Abdominal activity was uncommon on the exercise but common on the rest and dipyridamole scans. The exercise scans differed from the rest and dipyridamole scans in the subgroups: intensity of abdominal activity equal to myocardium, and greater than myocardium (P < 0.001). There was no difference between the rest and dipyridamole scans. The effect on evaluation was moderate in 5% of the exercise, 46% of the dipyridamole and 37% of the rest scans, and severe in 1% of the exercise, 3% of the dipyridamole and 12% of the rest scans. Rest differed from exercise (P < 0.001) and from dipyridamole (P < 0.05). There was no difference between the dipyridamole and exercise scans. Based on the clinical reports, abdominal activity was a limitation to scan interpretation for 20 patients; in 5, the inferior wall could not be evaluated. Although abdominal activity was frequently observed on both the dipyridamole and rest scans, it was a limitation to clinical interpretation in a small fraction of the patients.

Clinical impact of colonoscopic screening in first-degree relatives of patients with hereditary non-polyposis colorectal cancer.

Sixty-one asymptomatic individuals with an affected first-degree relative from five large hereditary non-polyposis colorectal cancer (HNPCC) kindreds were screened by colonoscopy. Neoplasms were found in nine (15 per cent) of 61 individuals on the first screen. Five subjects had a single adenoma while two had two adenomas each. There were two patients (3 per cent) with malignant neoplasms: one with a Dukes B adenocarcinoma and one with synchronous Dukes C adenocarcinomas in the caecum and ascending colon. These findings support the hypothesis that adenomas do not occur in large numbers in HNPCC families but, because of the high malignant conversion rate, biennial colonoscopy with removal of polyps seen is recommended.

Subvalvular left ventricular outflow tract obstruction caused by "rhinonodular" calcification.

Cardiac calcification is a common problem in patients with renal failure. Calcific deposits often affect the mitral annulus, the aortic valve, and the coronary arteries. We report an atypical case of cardiac calcification obstructing the left ventricular outflow tract with minimal aortic valve calcification.

Accurate combination of CT and MR data of the head: validation and applications in surgical and therapy planning.

A method is presented for the accurate combination of magnetic resonance (MR) and computed tomographic (CT) images of the head. Our technique is based on user identified 3D landmarks followed by data combination and display as adjacent slices, a single fused slice representation, colour overlay and three-dimensional (3D) rendered scenes. Validation with a point phantom and computer simulation has established the relationship of registration accuracy with point location accuracy, the number of points used and their spatial distribution. The technique is in clinical use in the planning of skull base surgery, transferring MR images acquired without a stereotaxic frame to stereotaxic space, and staging and planning therapy of nasopharyngeal tumours.

Mid-infrared laser reflectance of moist soils.

The effect of varying moisture content on the mid-infrared (9-11-µm) laser backscatter reflectance of different soils was investigated experimentally. Total reflectance was separated into a diffuse and a coherent component. Consistent with observations in the visible and near-infrared spectral regimes, the diffuse mid-infrared reflectance values decrease with increasing gravimetric moisture content. At low moisture contents, this phenomenon is attributed to increased forward scattering, while total internal reflection at the water-air interface results in lower reflectance values at higher moisture contents. The coherent component, however, increases initially for low moisture content as a result of the reduction in surface roughness on moistening, decreases subsequently, and then tends to increase again as the moisture content nears the field capacity of the soil. An empirical model based on the above physical mechanisms is developed for the diffuse component and tested by using the measured data. It is conjectured that the laser reflectance is sensitive to moisture in the surface layer (≃ 0.25-mm depth) and thus may have the potential to monitor near-surface soil moisture.

Glove perforation during surgery: what are the risks?

Surgical gloves are important in protecting medical staff from exposure to pathogens during surgery, especially viruses such as hepatitis B and the human immunodeficiency virus. We have studied the incidence and circumstances of surgical glove perforation using a sensitive electronic device. The glove perforation rate during elective general surgery was compared with that seen during an anastomosis workshop, where surgical trainees operated in a laboratory setting. A total of 220 gloves were tested for perforations pre- and postoperatively during general elective surgical procedures. During the surgical training workshop 72 gloves were tested. Fifty-two gloves (24%) were perforated during surgical procedures. Among surgeons, consultants had a significantly lower perforation rate than trainees (26% vs 46%, P < 0.05, chi 2), that for assistants was much lower (9%). The perforation rate for scrub nurses was surprisingly high at 22%. Glove perforation among trainees was significantly lower during workshop procedures than at elective surgery (17% vs 46%, P < 0.05, chi 2), probably because glove perforation occurs commonly at wound closure. Glove perforation remains very common, particularly among surgical trainees. Glove perforation should be reduced by teaching better techniques, especially 'no-touch', particularly for wound closure.

Participation of the cysteinyl leukotrienes in the acute bronchoconstrictor response to inhaled platelet activating factor in man.

To determine whether the effects of platelet activating factor on the airways may be due to the production of leukotrienes we studied the effects of pretreatment with the selective cysteinyl leukotriene antagonist SK&F 104353-Z2 on the airway and cellular responses to inhaled platelet activating factor. Eight healthy men were studied in a randomised, double blind placebo controlled cross-over study. A single dose of platelet activating factor that caused a fall of at least 35% in specific airways conductance (sGaw) was determined initially for each subject. Challenge with this dose of platelet activating factor was then carried out on two further occasions after pretreatment with a single nebulised dose of SK&F 104353-Z2 or placebo. The % reductions in specific airways conductance and of partial flow at 30% of vital capacity (PVmax30) were less after SK&F 104353-Z2 than after placebo (22 versus 34 for sGaw, 19 versus 31 for PVmax30). The mean (95% confidence limits (CL] differences in the maximum % fall from control values for SK&F 104353-Z2 and placebo were -12.6 (-23.8, -1.4) for sGaw and -12.5, (-20.8 -4.2) for PVmax30. The mean % fall in neutrophil count was similar after SK&F 104353-Z2 (46%) and after placebo (50%) (95% CL of difference 13.6, 6.6). Bronchial responsiveness to methacholine did not increase above baseline values in any subject when measured two weeks after challenge by platelet activating factor. This study suggests that leukotrienes play a part in the response to platelet activating factor in man.

Platelet activating factor does not cause a reproducible increase in bronchial responsiveness in normal man.

The reproducibility of acute effects of inhaled PAF on airway calibre, circulating neutrophil count and any subsequent increase in bronchial responsiveness has been studied in six normal subjects and compared to the effects of inhaled lyso-PAF, the inactive precursor and metabolite of PAF. PAF caused acute bronchoconstriction and a transient fall in neutrophil count on two separate occasions in five out of six subjects (minimum percentage of baseline values (mean): first PAF challenge; sGaw 69%, Vmax30 72%; neutrophil count 70%; second PAF challenge; sGaw 61%, Vmax30 74%, neutrophil count 63%). In one subject inhaled PAF caused bronchoconstriction and a transient fall in neutrophil count once, but a second challenge resulted in no detectable changes. There was no significant increase in bronchial responsiveness to methacholine in any subject studied on five occasions over a 2-week period following each PAF challenge. Challenge with lyso-PAF did not cause acute effects or any subsequent changes in bronchial responsiveness. These findings demonstrate that any effects of inhaled PAF on bronchial responsiveness in normal man are small and probably not of clinical significance. It would also be inappropriate to use this human model to study the mechanisms of bronchial hyperresponsiveness or for the preliminary assessment of potential new anti-asthma drugs.

Body temperature in elderly surgical patients.

Body temperatures of 37 elderly surgical patients with fractured hips were measured using tympanic membrane probes. Comparisons were made between patients having the usual body coverings, eight were hypothermic as compared with one of 16 patients with extra body coverings. Temperatures were significantly different between groups intraoperatively (p less than .001) and in the recovery room p less than .002) where the lowest temperatures were recorded. Anxiolytics given preoperatively had a significant negative relationship with lower body temperatures. Careful monitoring of temperatures and extra coverings are recommended for elderly hip fractured patients perioperatively.