Electrostatically Guided Rydberg Positronium

We report experiments in which positronium (Ps) atoms were guided using inhomogeneous electric fields. Ps atoms in Rydberg-Stark states with principal quantum number n=10 and electric dipole moments up to 610 D were prepared via two-color two-photon optical excitation in the presence of a 670  V cm^{-1} electric field. The Ps atoms were created at the entrance of a 0.4 m long electrostatic quadrupole guide, and were detected at the end of the guide via annihilation gamma radiation. When the lasers were tuned to excite low-field-seeking Stark states, a fivefold increase in the number of atoms reaching the end of the guide was observed, whereas no signal was detected when high-field-seeking states were produced. The data are consistent with the calculated geometrical guide acceptance.

Controlling Positronium Annihilation with Electric Fields

We show that the annihilation dynamics of excited positronium (Ps) atoms can be controlled using parallel electric and magnetic fields. To achieve this, Ps atoms were optically excited to n=2 sublevels in fields that were adjusted to control the amount of short-lived and long-lived character of the resulting mixed states. Inclusion of the former offers a practical approach to detection via annihilation radiation, whereas the increased lifetimes due to the latter can be exploited to optimize resonance-enhanced two-photon excitation processes (e.g., 1^{3}S→2^{3}P→nS/nD), either by minimizing losses through intermediate state decay, or by making it possible to separate the excitation laser pulses in time. In addition, photoexcitation of mixed states with a 2^{3}S_{1} component represents an efficient route to producing long-lived pure 2^{3}S_{1} atoms via single-photon excitation.

A trap-based pulsed positron beam optimised for positronium laser spectroscopy

We describe a pulsed positron beam that is optimised for positronium (Ps) laser-spectroscopy experiments. The system is based on a two-stage Surko-type buffer gas trap that produces 4 ns wide pulses containing up to 5 × 10(5) positrons at a rate of 0.5-10 Hz. By implanting positrons from the trap into a suitable target material, a dilute positronium gas with an initial density of the order of 10(7) cm(-3) is created in vacuum. This is then probed with pulsed (ns) laser systems, where various Ps-laser interactions have been observed via changes in Ps annihilation rates using a fast gamma ray detector. We demonstrate the capabilities of the apparatus and detection methodology via the observation of Rydberg positronium atoms with principal quantum numbers ranging from 11 to 22 and the Stark broadening of the n = 2 → 11 transition in electric fields.

Selective production of Rydberg-stark states of positronium

Rydberg positronium (Ps) atoms have been prepared in selected Stark states via two-step (1s→2p→nd/ns) optical excitation. Two methods have been used to achieve Stark-state selection: a field ionization filter that transmits the outermost states with positive Stark shifts, and state-selected photoexcitation in a strong electric field. The former is demonstrated for n=17 and 18 while the latter is performed for n=11 in a homogeneous electric field of 1.9  kV/cm. The observed spectral intensities and their dependence on the polarization of the laser radiation are in agreement with calculations that include the perturbations of the intermediate n=2 manifold. Our results pave the way for the generation of Rydberg Ps atoms with large electric dipole moments that are required for the realization of schemes to control their motion using inhomogeneous electric fields, an essential feature of some proposed Ps free-fall measurements requiring focused beams of long-lived atoms.

The C-terminal tail of tetraspanin proteins regulates their intracellular distribution in the parasite Trichomonas vaginalis

The parasite Trichomonas vaginalis is the causative agent of trichomoniasis, a prevalent sexually transmitted infection. Here, we report the cellular analysis of T.vaginalis tetraspanin family (TvTSPs). This family of membrane proteins has been implicated in cell adhesion, migration and proliferation in vertebrates. We found that the expression of several members of the family is up-regulated upon contact with vaginal ectocervical cells. We demonstrate that most TvTSPs are localized on the surface and intracellular vesicles and that the C-terminal intracellular tails of surface TvTSPs are necessary for proper localization. Analyses of full-length TvTSP8 and a mutant that lacks the C-terminal tail indicates that surface-localized TvTSP8 is involved in parasite aggregation, suggesting a role for this protein in parasite : parasite interaction.

Protein palmitoylation inhibition by 2-bromopalmitate alters gliding, host cell invasion and parasite morphology in Toxoplasma gondii

Protein palmitoylation is the reversible covalent attachment of palmitic acid onto proteins. This post-translational modification has been shown to play a part in diverse processes such as signal transduction, cellular localization and regulation of protein activity. Although many aspects of protein palmitoylation have been identified in mammalian and yeast cells, little is known of this modification in Toxoplasma gondii. In order to determine the functional role of protein palmitoylation in T. gondii, tachyzoites were treated with the palmitoylation inhibitor 2-bromopalmitate (2-BP). Parasites treated with 2-BP displayed a significant increase in non-circular trails which were longer than those trails left by non-treated parasites. Furthermore, 2-BP treatment reduced the invasion process to the host cells. Long-term treatment of intracellular tachyzoites resulted in major changes in parasite morphology and shape in a dose-dependent manner. These results suggest that palmitoylation could be modifying proteins that are key players in gliding, invasion and cytoskeletal proteins in T. gondii.

Correlation between Alt a 1 levels and clinical symptoms in Alternaria alternata-monosensitized patients

BACKGROUND

Alternaria alternata is a risk factor for developing asthma.Alt a 1, which has been described as the major allergen in A alternata, shows a good correlation with A alternata spores only when they have germinated.

OBJECTIVES

The objective of this study was to determine the correlation between spore counts and clinical symptoms in patients with allergic asthma and/or rhinitis monosensitized to A alternata.

METHODS

Two types of samplers were used to determine exposure: a Burkard spore trap to collect A alternata spores and a high-volume air sampler to collect airborne particles. A total of 366 air filters were collected. Alt a 1 levels were measured by monoclonal antibody-based enzyme-linked immunosorbent assay. Eighteen monosensitized patients were asked to record their daily symptoms throughout the year.

RESULTS

A alternata spores were detected throughout the year, whereas Alt a 1 was detected only between March and December. Symptoms showed positive and significant correlations with spore counts (r=0.459, P<.001), and Alt a 1 levels (r=0.294, P<.001). The correlation between spores and Alt a 1 was low. The negative binomial model proved that an increase of 10 pg/m3 in Alt a 1 levels increased the number of symptoms at a 3-day lag by 5%.

CONCLUSIONS

In patients who are allergic to A alternata, Alt a 1 levels can be considered an important marker for predicting the risk of respiratory symptoms.

The impact of conservation on the status of the world's vertebrates

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species.

Grass pollen, aeroallergens, and clinical symptoms in Ciudad Real, Spain

BACKGROUND

In allergic individuals, onset of symptoms is related to atmospheric pollen grain counts and aeroallergen concentrations. However, this relationship is not always clear.

OBJECTIVES

To analyze the correlation between grass pollen grain and aeroallergen concentrations in Ciudad Real, Spain, during the year 2004 and establish their association with symptoms in patients with allergic asthma, rhinitis, or both.

METHODS

Two different samplers were used to assess allergen exposure: a Burkard spore trap to collect pollen grains and a high-volume air sampler to collect airborne particles. Individual filters were extracted daily in phosphate-buffered serum and analyzed by enzyme-linked immunosorbent assay based on serum containing high titers of specific immunoglobulin (Ig) E to grasses. The study population comprised 27 grass-allergic patients whose symptoms and medication were recorded daily.

RESULTS

Grass pollens were detected between April 28 and July 18. There was a positive correlation between pollen grain counts and symptoms (r = 0.62; P > .001). Grass aeroallergens were detected not only during the grass pollination period, but also before and after this period. There was also a very significant correlation between aeroallergen levels and symptoms (r = 0.76; P < .0001). The threshold level for grass pollen was 35 grains/m3.

CONCLUSIONS

Grass-related allergenic activity is present throughout the year, demonstrating the existence of aeroallergens outside the pollen season. Symptoms in allergic patients may be related to airborne particle concentrations. This fact should be taken into account in the clinical follow-up and management of allergic patients.

Air pollution and seasonal asthma during the pollen season. A cohort study in Puertollano and Ciudad Real (Spain)

BACKGROUND

Many studies have demonstrated a positive association between air pollutants and emergency visits for asthma. However, few studies have included pollen when analysing this relationship in mild-moderate asthmatic patients.

OBJECTIVE

To determine the importance of the pollutants such as ozone (O(3)), particles (PM(10)), nitrogen dioxide (NO(2)) and sulphur dioxide (SO(2)) in the clinical course of mild-moderate pollen-allergic asthmatic patients from two Spanish towns in La Mancha: Puertollano (high pollution levels) and Ciudad Real (low pollution levels).

METHODS

We used a Poisson regression model to study a cohort of 137 patients from Puertollano and Ciudad Real during two pollen seasons (2000-2001) and analysed the relationship between air pollutant and pollen levels and daily symptoms, the medication used and peak-flow measurements.

RESULTS

The number of asthma symptoms and the mean values of the PM(10), SO(2) and NO(2) levels were higher in Puertollano than in Ciudad Real. In Puertollano, the risk of asthma increased by 6% with a 3-day lag for PM(10), by 8% with a 3-day lag for O(3), by 4% with a 1-day lag for SO(2) and by 15% with a 3-day lag for O(3) when its values exceeded the health threshold (P < 0.05).

CONCLUSIONS

The air pollution levels in Puertollano were associated with an increased risk of asthma symptoms in pollen-allergic asthmatic patients com pared with a similar group from Ciudad Real.

Contrast-enhanced sonography during uterine artery embolization for the treatment of leiomyomas

Uterine artery embolization (UAE) is a successful and safe treatment for symptomatic leiomyomas. However, rare complications such as premature menopause and uterine necrosis can arise because of embolization of non-target tissues. We studied the feasibility of using contrast-enhanced sonography with intravenous SonoVue just before, during and after complete occlusion of both uterine arteries. In a patient with multiple, large, symptomatic leiomyomas, contrast-enhanced imaging established that the UAE was technically successful and that myometrial vascularity was not reduced. Our case suggests that ultrasound contrast agents may have a role in monitoring UAE and thus may help prevent ischemic complications. Further studies are required to confirm this.

[Prospective clinical and sonographic assessment of uterine artery embolization as the treatment of symptomatic uterine leiomyomata]

OBJECTIVE

To evaluate the effectiveness of the uterine artery embolization as the treatment of symptomatic uterine leiomyomata.

PATIENTS AND METHODS

Eighty-five women with symptoms caused by uterine leiomyomata underwent uterine artery embolization as an alternative to surgery from january 1997 to june 2000. The effectiveness of this method was evaluated by clinical and sonographic examination.

RESULTS

The recession average was of 18.9 months. There were ten failures. We had immediate failures (n = 5) with a case of technical failure, one endometrium cancer, one adenomyosis, one larger subserosal leiomyomata and one parametrial leiomyomata. We had recurrences (n = 5) with the occurrence of new leiomyomatas (1 intramural and 3 submucosal) and an evolution of previous leiomyomata. The average volume reduction was 51% for the uterus and 65% for the main fibroid at one year follow-up. Minor complications occurred in 5%. Permanent amenorrhoea was observed for 3.75% of the women. Using cox model, no predictive factors of embolisation effectiveness were found.

DISCUSSION AND CONCLUSION

In the treatment of symptomatic uterine leiomyoma, uterine artery embolization is an effective alternative to surgery. After one year and half, we had 12.5% of failures.

Familial choanal atresia with maxillary hypoplasia, prognathism, and hypodontia

We report on two sibs and a cousin with bilateral choanal atresia. At 2 months, one sib died of complications following surgical correction of her defects. We evaluated her brother and cousin at age 7 and 9 years, respectively. Both had a tall forehead, maxillary hypoplasia, prognathism, and absence of certain deciduous and permanent teeth. Psychomotor development was appropriate for age. Roentgenocephalometric analyses of several relatives showed that one grandfather of these children and two of the five uncles and aunts also had maxillary hypoplasia and/or prognathism. To our knowledge, this condition has not been described previously and may represent a newly recognized autosomal dominant condition with incomplete penetrance and variable expressivity caused by a defect of neural crest development.

[Guidelines of the Spanish Society of Cardiology on valve heart disease]

Valvular heart diseases, which continue to be a major cause of morbidity and mortality world wide, have undergone radical changes since the first valve prostheses were implanted 40 years ago. These changes have been the result of both scientific progress and improved standard of living in developed countries. The availability of penicillin to treat streptococcal pharyngitis and less crowded living conditions have now made rheumatic fever uncommon in these countries. However, other forms of valve impairment have appeared over the past several years. The etiology of some of these valvular diseases remains obscure (e. g. myxomatous mitral valve); others, such as the senile type of calcific aortic valve stenosis, seem to be the price to be paid for the extension of life expectancy. With regard to diagnosis, echocardiography has constituted a formidable tool for visualizing anatomic valve changes, interpreting complex hemodynamic derangements, and evaluating repercussion on the left ventricle. In addition, the iteration of this non-invasive examination has allowed a much better understanding of the natural history of non-severe valvular disease and therefore of the precise timing for surgical intervention, without awaiting, in most cases, the appearance of advanced symptomatology. This has also been possible because of the great advances in cardiac surgery which can be summarised as: a) the improvement in extracorporeal circulation and myocardial preservation techniques; b) the greatly improved biologic and mechanic valve substitutes; c) the introduction of imaginative mitral valve repair procedures, and d) the use of intraoperative transesophageal echocardiography to assess the adequacy of valve repair. At the same time, percutaneous catheter balloon valvuloplasty has emerged as a valid alternative to mitral surgical commissurotomy for mitral stenosis. All these changes, and many more that can not be described in this brief summary, make a review of the management of patients with valve heart disease appropriate.

[Guidelines of the Spanish Society of Cardiology for clinical practice in exercise testing]

Most exercise testing is performed in adults with known or suspected ischemic heart disease. In the last few years cardiac imaging techniques have been applied in this field, improving the information obtained with the procedure. However, the exceptions to this rule are emerging rapidly not only in healthy people (asymptomatic individuals, athletes, handicapped people) but also in cardiac patients (advanced congestive heart failure, hypertension, rhythm disorders, congenital heart disease, etc.). All the-se issues justify the need for a multidisciplinary consensus document in Spain. This paper reviews and updates the methodological aspects of the stress test, including those related to oxygen consumption measurements. The main aim of this review was to determine the role of exercise testing in the evaluation of ischemic heart disease as well as the applications of imaging stress testing. The usefulness of this test in other non-ischemic cardiac disorders and in selected subsets of healthy people is also reviewed.

[Varicella pneumonia during pregnancy after double exposure in the 2nd trimester. Value of seroprophylaxis]

We report on a case of varicella pneumonia at 29 weeks of gestation after double contact during the second trimester of pregnancy although passive immunotherapy by polyvalent immunoglobulins was used. Our case report highlights the difficulties of varicella pneumonia diagnosis that was here confirmed by seroconversion and the presence of pathognomonic microcalcifications, on a pulmonary X-ray, realized two years after pregnancy. Although the absence of publications asserting the efficacy of immunotherapy by polyvalent immunoglobulins to prevent maternal complications of varicella during pregnancy, they remain widely employed in such cases. Our point of view is that this indication must be revisited.

Case report and review of the literature: primary twin ovarian pregnancy

A case report of primary twin ovarian pregnancy is presented. A 36 year old woman, gravida 4 para 3, was admitted to the hospital for suspected ectopic pregnancy, with vaginal bleeding at 11 weeks after her last menstrual period, associated with pelvic pain. An endovaginal ultrasonography led to the diagnosis of twin ovarian right ectopic pregnancy with two dead fetuses associated with a compartmentalized haemoperitoneum. Unilateral oophorectomy was carried out by laparotomy. Histological studies confirmed an uni-ovular di-amniotic ovarian pregnancy. Seven cases of ovarian twin pregnancies are reviewed in the literature. This case is the first one where diagnosis has been made by endovaginal sonography.

[Epidemiology of neurosensorial deafness in the Foral Community of Navarra]

Congenital deafness is a relatively frequent disorder that shows a heterogeneous aetiology. Knowledge and the control of some risk factors have decreased the incidence of acquired deafness and increased the relative importance of genetic cause. In an attempt to investigate the clinical relevance of congenital deafness and the mechanisms of prevention in our population, a clinical and genetic study of cases with neurosensorial deafness born in Navarra between 1975 and 1990 was carried out. A total of eighty-one cases were identified, giving an incidence of 0.8 per thousand. Thirty per cent of the cases showed deafness associated with defects. Cause of deafness was identified in seventy per cent of the cases with whom a detailed clinical and genetic study could be performed (n=50). Genetic factors were responsible for the disorder in more than half of these cases. The most frequent hereditary factor was of the autosomic recessive type. This was associated with a more severe form of hearing loss.

[Effect of prosthesis type and size on the hemodynamic response of mitral valve prostheses to exertion]

BACKGROUND

Doppler echocardiography is current tool for hemodynamic evaluation of mitral prosthetic heart valves. It's accepted that the area and the gradients by Doppler echocardiography are not influenced at rest by valvular type and valvular size. We evaluated the influence of valvular type, mechanical-biological, and size on exercise hemodynamic of normally-functioning mitral prosthesis. Thirty-seven patients with mitral prosthesis, mean age 56 +/- 10 years, underwent exercise Doppler echocardiography. Peak and mean prosthetic gradient were obtained at rest, during and at maximal exercise with a nonimaging transducer. Mechanical prosthesis were 23 and biological valves 14. Valvular size was less than 26 mm in 7 patients and more than 28 mm in 20 patients. Exercise increased the heart rate from 80 +/- 14 to 143 +/- 22 (p < 0.001), peak gradient from 11.4 +/- 4 to 26.1 +/- 7 mm Hg (p < 0.001) and mean gradient from 4.8 +/- 1 to 13.7 +/- 5 mm Hg (p < 0.001). We found similar peak (11.4 +/- 3 & 11.3 +/- 4) and mean gradient (3.4 +/- 1 & 2.9 +/- 0.7) at rest between mechanical and biological valves; at maximum exercise, peak (26 +/- 7 & 26 +/- 6) and mean gradient (13.9 +/- 6 & 13.2 +/- 4) were also similar. Prosthesis with > 28-mm-size compared with prosthesis < 26-mm-size showed minor peak gradient at second step (21.3 +/- 4 & 26.4 +/- 6, p < 0.05) and at peak exercise (25.4 +/- 7 & 29.8 +/- 8, ns). Hemodynamics on exercise using Doppler echocardiography was not influenced by valvular type (mechanical-biological) in normal mitral prosthesis. However, mitral prosthesis of small size showed worse on hemodynamics exercise than bigger ones.

Repair of radiation-induced vesicovaginal fistula with a rectus abdominis myocutaneous flap

The cutaneous RAM flap was used successfully to repair a radiation-induced vesicovaginal fistula. Patient selection is important, ideally one with a fatty lower abdominal wall and without a previous incision transecting the inferior rectus muscle below the umbilicus. The RAM flap has excellent vascularity, allows augmentation of the bladder, and permits an extraperitoneal approach, factors that are important when operating in an irradiated field.

A computer system for epidemiological surveillance

In epidemiological surveillance, it is imperative that any unusual increase in reported cases be detected as quickly as possible. In the surveillance unit at "Pedro Kourí," it was necessary to create a computer system for the surveillance of transmissible diseases in order to manage such variables as morbidity, mortality, and the circulation of causal agents. As usage flexibility is a fundamental requirement, we developed VIGILA as a system readily adaptable to any level of the country's health organizations (national, provincial, or municipal). VIGILA permits the storage, validation, and statistical analysis of morbidity and mortality data, and it also allows the user to apply these features to causal agent information. These manipulations are all performed in the context of a specific transmissible disease. The stored information can be displayed in different types of statistical formats, such as calculated rates, accumulates and medians. The user can also design his/her own tables for display. In addition, the program offers graphics that depict the endemic forecast for a specific region and age group. Reliable forecasts based on temporal models of an epidemiological indicator are necessary for the prediction of the non-epidemic indicator and for the elaboration of an alert threshold. The endemic forecast or endemic channel is calculated by means of a modified version of R. Serfling's model [1] which adapts to data series with stationary characteristics. In this case, the model is fixed for the medical attention protocol and the circulation of agents of a specific transmissible disease. The parameters of the model are estimated by the least square method. The confidence limits are calculated with the T-Student distribution [2]. To enter information about a specific disease and level of health concern, the user must define the disease under analysis, the principal territory under surveillance and its dependencies, the causal agents of the disease, and the frequency with which the disease is reported. This system stores the number of cases (morbidity) and death (mortality) that occurred in the territories and age groups defined during entry. To facilitate the calculation of morbidity and mortality rates, information pertaining to the number of territory habitants and their age groups is also stored. The laboratory data includes the number of analyzed samples in the territories and age groups defined in the data entry, and the samples that were positive to the defined agents. Among the principal uses of the system are: calculation of cumulative cases, rates, and cumulative rates for the specific period of analysis, territory, and age group; comparison of these health indicators with the previous year's indicators or with the median of the previous years' indicators' calculation of the endemic forecast that permits the user to observe the epidemiological situation by territories and age groups; and the early detection of an increase in disease occurrence. The system also offers a geographical representation of the epidemiological situation in the territories, showing a map with the evaluation of each territory with respect to four possible risk factors. VIGILA is available in both DOS and WINDOWS 3.1 formats. This system allows the evaluation of the situation at a specific point in time in the analyzed territories, and may alert the infection control team to an epidemic early enough to allow implementation of control measures.