A close shave? Performance of P2/N95 respirators in healthcare workers with facial hair: results of the BEARDS (BEnchmarking Adequate Respiratory DefenceS) study.

P2/N95 filtering face piece respirators (FFRs) protect healthcare workers (HCWs) from airborne infections. This study assessed the impact of facial hair on quantitative respirator fit in 105 male HCWs, of whom 38 were clean shaven, and assessed the prevalence of male facial hair at the study facility. Only 34 (32%) male HCWs overall achieved an adequate FFR fit, including 47% of clean-shaven men. No full-bearded HCWs achieved a fit. Adequate respirator fit decreased significantly with increasing facial hair (P<0.01 for trend). Facial hair was present on 49% of male employees. This study supports quantitative fit testing prior to P2/N95 respirator use.

Sexual health and rehabilitation after ovarian suppression treatment (SHARE-OS): a clinical intervention for young breast cancer survivors.

PURPOSE: Each year, thousands of young breast cancer (BC) patients confront the difficult decision to medically suppress ovarian function and undergo abrupt, premature menopause to reduce risk of cancer recurrence. Unlike natural menopause, young women undergoing ovarian suppression (OS) face severe and disruptive side effects. Profound sexual dysfunction is one of the most prevalent, distressing side effects of OS treatment. Unmanaged sexual dysfunction is also a primary predictor of non-adherence to this potentially life-saving treatment. We developed and tested a brief, psychosexual intervention targeted to manage sexual dysfunction and psychological distress after OS in young BC survivors. METHODS: Twenty young BC survivors with sexual dysfunction received a single 4-h group intervention that included sexual health rehabilitation, body awareness exercises, and mindfulness-based cognitive therapy (MBCT) skills followed by a single tailored booster telephone call 1-month later. Assessment of female sexual function and psychological distress was completed at baseline and 2 months post-intervention. RESULTS: Analyses examined changes pre- to post-intervention. Female sexual health improved significantly from baseline to follow-up (n = 19, p < 0.02). Anxiety was also significantly improved at the 2-month (p < 0.000) timepoint, compared with baseline 1. Moderate-to-large effect sizes were observed regarding changes in sexual function and psychological distress. CONCLUSIONS: Significant improvements in sexual functioning and psychological distress were observed 2 months post-intervention. IMPLICATIONS FOR CANCER SURVIVORS: These results demonstrate that delivery of a targeted intervention in brief, low-intensity group setting is a promising model for reducing distressing sexual dysfunction in young BC survivors on OS treatment.

Synchronization of two ensembles of atoms.

We propose a system for observing the correlated phase dynamics of two mesoscopic ensembles of atoms through their collective coupling to an optical cavity. We find a dynamical quantum phase transition induced by pump noise and cavity output coupling. The spectral properties of the superradiant light emitted from the cavity show that at a critical pump rate the system undergoes a transition from the behavior of two independent oscillators to the phase locking that is the signature of quantum synchronization.

[Preoperative cardiac assessment using dobutamine stress echocardiography]. / Evaluation du risque cardiaque avant chirurgie programmée par l'échocardiographie dobutamine.

Postoperative myocardial ischaemia is the leading cause of life expectancy impairment after high cardiac risk surgical procedures. Preoperative identification of patients at high risk for such complication helps reducing its postoperative incidence through therapeutic adjustments. The former relies upon preoperative selection of patients who are candidates for cardiac testing using dobutamine stress echocardiography, according to ACC/AHA guidelines. This exam evaluates echographic myocardial response to a pharmacological stress induced by dobutamine infusion. Its aim is to reproduce part of the stress the myocardium will undergo during surgical procedure. A stress induced myocardial ischaemia suggests such a complication could occur postoperatively. A positive dobutamine stress echocardiography justifies to prescribe preoperative anti-ischaemic treatment in order to reduce the cardiac risk of the further surgical procedure. Moreover, it justifies clear definition of perioperative haemodynamic objectives. Whatever the result of the dobutamine stress echocardiography, cardiac ischaemia should be monitored up to the third postoperative day on the basis of a daily 12-lead electrocardiogram recording and daily plasmatic troponin Ic measurement.

Nerve growth factor- and neurotrophin-3-releasing guidance channels promote regeneration of the transected rat dorsal root.

Dorsal roots have a limited regeneration capacity after transection. To improve nerve regeneration, the growth-promoting effects of the neurotrophins nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3) were evaluated. The proteins were continuously released by synthetic nerve guidance channels bridging a 4-mm gap in the transected dorsal root. Four weeks after lesion, the regenerated nerve cables were analyzed for the presence of myelinated and unmyelinated axons. While BDNF showed a limited effect on axonal regeneration (863 +/- 39 axons/regenerated nerve, n = 6), NGF (1843 +/- 482) and NT-3 (1495 +/- 449) powerfully promoted regeneration of myelinated axons compared to channels releasing the control protein bovine serum albumin (293 +/- 39). In addition, NGF, but not BDNF nor NT-3, had a potent effect on the regeneration of unmyelinated axons (NGF, 55 +/- 1.4; BDNF, 4 +/- 0.3; NT-3, 4.7 +/- 0.3 axons/100 microm(2); n = 6). The present study suggests that synthetic nerve guidance channels slowly and continuously releasing the neurotrophins NGF and NT-3 can overcome the limited regeneration of transected dorsal root.

Diuretic renography and angiotensin converting enzyme inhibitor renography.

Renovascular hypertension and renal outlet obstruction are two clinical conditions well evaluated by nuclear medicine techniques. They both require a specific intervention to challenge a specific aspect of renal functional reserve. Diuretic renography is the oldest common example in nuclear medicine where functional change in the kidney is provoked for diagnostic purposes. The kidney's tubular functional reserve, in this instance, is challenged to induce diuresis and increase urine flow. This intervention permits diuretic renography to retain an essential role in the evaluation of hydroureteronephrosis. Captopril renography is a more recent example of a similar principle and depends on a reactive renin-angiotensin system to identify a kidney responsible for RVH. In both renal outlet obstruction and RVH, an anatomic abnormality is also identified (hydronephrosis and RAS, respectively) at some point in the diagnostic workup. The final diagnosis in each instance, however, depends on evidence for a functional disorder, provoked and measured during the radionuclide interventional examination. These serve as excellent examples of the power of functional imaging to identify specific medical disorders.

Does meaning matter? The impact of word knowledge on lateral masking.

BACKGROUND: Many older adults have lost the use of their foveae due to disease. Because of this, they must use peripheral retina to do tasks formerly done using the fovea, such as letter identification and reading. Several researchers have recently proposed that reading in the periphery is limited by lateral masking: the reduced perceptibility of a target when it is surrounded by flanking stimuli. None of these studies tested the perceptibility of letters within words, where the semantic relationship between the target letter and the flanking letters is likely to improve perceptibility. This study sought to determine whether the semantic relationship between the flanking stimuli and the target stimulus affects perceptibility of letters in the periphery. METHODS: Young, normally-sighted observers identified single letters and the middle letters of three-letter words, trigrams, and letters flanked by x's (xax) presented for 150 ms at 10 degrees eccentricity on each of the primary meridia. In the first experiment, subjects identified letters presented alone and letters flanked by one x on either side. In the second experiment, subjects identified the middle letters of words, trigrams, and xax stimuli, which were either presented in blocks or randomly. In the third experiment, only the words and trigrams were used, and subjects were required to both identify the middle letter and simultaneously indicate whether the stimulus was a word or a trigram. RESULTS: The first experiment showed that single letters were identified about 50% more accurately than letters flanked by x's. In the second and third experiments, letter identification was better when the target and flanking letters formed a word than when they formed a trigram and better along the horizontal meridian than along the vertical meridian, which is consistent with previous studies. In the third experiment, the subject's ability to identify the stimulus type had a significant impact on performance. When the stimuli were words, subjects identified the middle letter on 87% of trials when they correctly identified the stimulus and 40% of the trials when they did not; for the trigrams these percentages were 65% and 5%. CONCLUSIONS: When the flanking letters and the target letter formed a word, observers were better able to identify the target than when they did not form a word, and this pattern was mediated by the observers' knowledge of stimulus type. These data suggest that to draw conclusions regarding the impact of lateral masking on reading, the stimuli used should be words, not random-letter strings or other target/flanker combinations.

Parenchymal mean transit time analysis of 99mTc-DTPA captopril renography.

UNLABELLED: Proposed renal hemodynamic mechanisms of captopril suggest that quantitation of renographic retention parameters should help identify patients suspected of having renovascular disease. The parenchymal mean transit time (MTT) is theoretically superior to other measures of retention, but data supporting its superiority are few. METHODS: Two groups of subjects were studied with diethylenetriamine pentaacetic acid (DTPA) baseline and captopril renography, one (n = 43) with demographically defined essential hypertension (group I) and the other (n = 60) with a high prevalence of renovascular disease (group II). Abnormal parenchymal MTT values were derived from the statistical confidence limits of group I data and then applied to group II subjects for comparison with angiographic results. RESULTS: Depending on the sensitivity of the threshold chosen, specificity varied, but the overall accuracy of baseline parenchymal MTT for renovascular hypertension detection ranged from 54% to 58%. Change in parenchymal MTT (post-captopril - pre-captopril) accuracy was 55%-61% and was not significantly different. Neither method improved on previously reported quantitative or qualitative criteria. Group II subjects had significantly worse renal function than did group I subjects, and 23% had nondiagnostic renograms. CONCLUSION: Parenchymal MTT analysis of DTPA captopril renography is not more accurate and offers no advantages compared with qualitative renography or with more commonly used renographic measures in our subjects. This may relate to the high prevalence of renal dysfunction in our population. In subjects with renal dysfunction, the low sensitivity and the trend toward low specificity of parenchymal MTT do not support its routine use for the evaluation of renovascular disease among patients suspected of having renovascular hypertension.

John Call Dalton, Jr., MD: America's first neurophysiologist.

Before the discoveries of John Call Dalton, Jr., MD (1824-1889), innervation of laryngeal muscles, long-term effects of cerebellar lesions, and consequences of raised intracranial pressure were poorly understood. Dalton discovered that the posterior cricoarytenoid muscles adducted the vocal cords during inspiration. He confirmed Flourens' observations that acute ablation of the cerebellum of pigeons caused loss of coordination. Dalton observed that properly cared for pigeons gradually recovered "coordinating power." Dalton observed that prolonged raised intracranial pressure caused tachycardia and then fatal bradycardia in dogs. Before Dalton published his photographic atlas of the human brain, neuroanatomy atlases were sketched by Europeans and imported into the United States. Dalton's atlas of the human brain contained precise photographs of vertical and horizontal sections that equal modern works. Before Dalton introduced live demonstrations of animals, physiology was taught by recitation of texts only. Dalton was the first American-born professor to teach physiology employing demonstrations of live animals operated on under ether anesthesia. He wrote an essay advocating experimentation on animals as the proper method of acquiring knowledge of function and that humane animal experimentation would ultimately improve the health of man and animals. His eloquent advocacy for humane experimental physiology quelled attacks by contemporaneous antivivisectionists. Dalton was America's first experimental neurophysiologist.

Orbital involvement as the initial manifestation of sarcoidosis: magnetic resonance imaging findings.

A 74-year-old man had diplopia, painful right ophthalmoplegia, proptosis, conjunctival injection, and facial skin lesions. Magnetic resonance imaging (MRI) revealed infiltration of the right intraorbital adipose tissue. Lesions were mixed low- and high-signal on T2-weighted images and enhanced on fat-suppressed T1-weighted postcontrast images. A skin biopsy revealed numerous noncaseating granulomas consistent with sarcoidosis. Treatment with corticosteroids and chlorambucil led to a full clinical recovery. Sarcoidosis should be considered in the evaluation of orbital pseudotumor in elderly patients, even if no systemic manifestations of sarcoidosis are present.

Reading with eccentric fixation is faster in inferior visual field than in left visual field.

PURPOSE: People with central field loss tend to fixate so that information falls in the inferior or left visual field. Studies of reading from a page of text suggest that using inferior field is advantageous relative to using left visual field. In this study, we investigated whether reading without eye movements in normal peripheral vision is better when text is presented in inferior or left visual field. METHODS: Reading rates were determined for retinally stabilized rapid serial visual presentation sentences of seven letter sizes, presented at 5 degrees in inferior and left visual field of six normal observers. RESULTS: When print size is appropriately magnified for peripheral viewing, reading speed in inferior field is faster than in left visual field. There is no significant difference between inferior and left visual field in the print size required to reach maximum reading speed. CONCLUSIONS: For reading tasks not involving eye movements, there is an advantage in eccentrically fixating such that text falls in inferior rather than left visual field.

Evidence that elevated glucose causes altered gene expression, apoptosis, and neural tube defects in a mouse model of diabetic pregnancy.

Congenital malformations, including neural tube defects (NTDs), are significantly increased in the offspring of diabetic mothers. We previously reported that in the embryos of a mouse model of diabetic pregnancy, NTDs are associated with reduced expression of the gene Pax-3, which encodes a transcription factor that regulates neural tube development, and that reduced expression of Pax-3 leads to neuroepithelial apoptosis. In this study, we used three approaches to test whether glucose alone could be responsible for these adverse effects of diabetes on embryonic development. First, primary culture of embryo tissue in medium containing 15 mmol/l glucose inhibited Pax-3 expression compared with culture in medium containing 5 mmol/l glucose. Second, inducing hyperglycemia in pregnant mice by subcutaneous glucose administration significantly inhibited Pax-3 expression (P < 0.05), as demonstrated by quantitative reverse transcription-polymerase chain reaction assay of Pax-3 mRNA, and also increased neural tube apoptosis (P < 0.05). NTDs were significantly increased in glucose-injected pregnancies when blood glucose levels were >250 mg/dl (P < 0.002) but not in moderately hyperglycemic pregnancies (150-250 mg/dl, P = 0.37). Third, phlorizin administration to pregnant diabetic mice reduced blood glucose levels and the rate of NTDs. As seen with glucose-injected pregnancies, the rate of NTDs in phlorizin-treated diabetic pregnancies was related to the severity of hyperglycemia, since NTDs were significantly increased in severely hyperglycemic (>250 mg/dl) diabetic pregnancies (P < 0.001) but not in moderately hyperglycemic pregnancies (150-250 mg/dl, P = 0.35). These two findings, that elevated glucose alone can cause the changes in Pax-3 expression observed during diabetic pregnancy and that the NTD rate rises with significant increases in blood glucose levels, suggest that congenital malformations associated with diabetic pregnancy are caused by disruption of regulatory gene expression in the embryo in response to elevated glucose.

Are the benefits of sentence context different in central and peripheral vision?

BACKGROUND: Sentence context increases reading speed relative to reading unrelated words. Previous studies of normal peripheral retina and in patients with central field loss (CFL) have come to different conclusions regarding the benefits of sentence context for reading in peripheral retina. Studies of normal peripheral vision presented the text to inferior visual field; it is presumed that most of the patients fixated using retina lateral to their scotoma. The goal of the current study was to determine whether the location of the text on the retina interacts with the usefulness of sentence context. METHODS: Normally sighted subjects read sentences and random lists of words presented at the fovea and at 50 to the left of and 50 inferior to fixation in visual field space. Texts were presented using rapid serial visual presentation (RSVP). RESULTS: The ratio of reading rates for sentences to random words (context gain) was the same in the inferior field (2.7 +/- 0.20) and at the fovea (2.6 +/- 0.26); context gain was greater in the left field (7.2 +/- 1.22). CONCLUSIONS: Sentence context increases reading speed regardless of the position of the text on the retina. Reading rates in peripheral retina are not decreased because of an inability to use sentence context.

Phosphorylcholine-containing polyurethanes for the control of protein adsorption and cell attachment via photoimmobilized laminin oligopeptides.

In this study, we synthesized a biomaterial whose surface inhibits non-specific protein and cell attachment. The polymer was designed to mimic the external cell plasma membrane properties through the introduction of particular chemical constituents of the cell membrane: phospholipid polar headgroups. This was done by copolymerizing phosphorylcholine (PC) groups into a polyurethane polymer backbone (PCPUR). Peptides known to induce specific cell attachment were subsequently bound to the surface of this copolymer in a photoadressible manner to obtain surfaces that allowed the attachment of cells in a specific pattern. Two polymers with different phosphorylcholine concentrations were synthesized and their bulk and surface properties were characterized through differential scanning calorimetry, wettability measurements, angle-resolved X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry. Protein and lipid adsorption investigation using optical waveguide light mode spectroscopy showed that the irreversible adsorption of both proteins and lipids is drastically reduced as a result of simultaneous contributions of the PC groups, molecular mobility and strong hydrophilicity of the polymers. Consequently, this leads to a marked reduction in the cellular attachment response, which further decreases with increasing PC concentration. Finally, when the polymer surface was photo-derivatized, attachment of the neural NG108-15 cell line occurred only on the areas of the PCPUR where the laminin CDPGYIGSR peptide sequence was photoimmobilized. Cell attachment was nevertheless found to be non-specific with respect to the peptide sequence used and reasons for such results are therefore discussed.

Effects of cataract and scotoma on visual acuity: a simulation study.

Central field loss (CFL) and cataract both decrease visual acuity. For patients with CFL, visual acuity is further reduced when the acuity target is more visually complex. We tested visual acuity for targets of varying complexity (letters alone, letters flanked by one or two x's on each side, and words) in subjects with normal vision and in the presence of a simulated cataract, simulated scotoma, and their combination (scotoma + cataract). Visual acuity was best with normal vision and worst with scotoma + cataract for all of the acuity targets. There was little difference in visual acuity between the letters alone and flanked letters, and visual acuity was best for words under all vision conditions. The cataract had a greater impact on visual acuity when the subject's central visual field was clear (normal vision) than when it was occluded by the simulated scotoma.