Gender gap in cystic fibrosis mortality

The authors conducted the largest study to date of survival in cystic fibrosis. The study cohort consisted of all patients with cystic fibrosis seen at Cystic Fibrosis Foundation-accredited care centers in the United States between 1988 and 1992 (n = 21,047), or approximately 85% of all US patients diagnosed with cystic fibrosis. Cox proportional hazards regression analysis was used to compare the age-specific mortality rates of males and females and to identify risk factors serving as potential explanatory variables for the gender-related difference in survival. Among the subjects 1-20 years of age, females were 60% more likely to die than males (relative risk = 1.6, 95% confidence interval 1.4-1.8). Outside this age range, male and female survival rates were not significantly different. The median survival for females was 25.3 years and for males was 28.4 years. Nutritional status, pulmonary function, and airway microbiology at a given age were strong predictors of mortality at subsequent ages. Nonetheless, differences between the genders in these parameters, as well as pancreatic insufficiency, age at diagnosis, mode of presentation, and race, could not account for the poorer survival among females. Even after adjustment for all these potential risk factors, females in the age range 1-20 years remained at greater risk for death (relative risk = 1.6, 95% confidence interval 1.2-2.1). The authors concluded that in 1- to 20-year-old individuals with cystic fibrosis, survival in females was poorer than in males. This "gender gap" was not explained by a wide variety of potential risk factors.

Detection of 16 gamma-ray pulsars through blind frequency searches using the Fermi LAT

Pulsars are rapidly rotating, highly magnetized neutron stars emitting radiation across the electromagnetic spectrum. Although there are more than 1800 known radio pulsars, until recently only seven were observed to pulse in gamma rays, and these were all discovered at other wavelengths. The Fermi Large Area Telescope (LAT) makes it possible to pinpoint neutron stars through their gamma-ray pulsations. We report the detection of 16 gamma-ray pulsars in blind frequency searches using the LAT. Most of these pulsars are coincident with previously unidentified gamma-ray sources, and many are associated with supernova remnants. Direct detection of gamma-ray pulsars enables studies of emission mechanisms, population statistics, and the energetics of pulsar wind nebulae and supernova remnants.

Defining a pulmonary exacerbation in cystic fibrosis

OBJECTIVES

Despite the central importance of pulmonary exacerbations (PExs) as an outcome measure in cystic fibrosis clinical trials, no standardized definition of PEx exists. We conducted a prospective, multicenter study to establish a standardized PEx definition and score for use in clinical trials, based on clinical status rather than on treatment decisions.

STUDY DESIGN

Subjects were 246 patients enrolled in the placebo arm of a randomized, controlled trial of tobramycin for inhalation. Physician-investigators completed PEx questionnaires on all subjects at scheduled intervals during the 6-month study, indicating new or worsening symptoms, physical examination findings, and impression of PEx status (presence or absence and severity). Logistic regression was used to assess the relative importance of each of the characteristics in predicting a PEx.

RESULTS

We developed 2 PEx scores that use easily ascertained symptoms and chest examination findings; one also includes change in forced expiratory volume in 1 second over the preceding month. Both scores were sensitive and specific for predicting the presence of a PEx (sensitivity, 86%; specificity, 86%). The scores were validated in subjects in the intervention arm of the trial.

CONCLUSION

We hope that the proposed PEx score might serve as a standardized outcome measure for future clinical trials in cystic fibrosis, allowing meaningful comparisons of study results.

Prevalence of chronic prostatitis in men with premature ejaculation

OBJECTIVES

To investigate the prevalence of chronic prostatitis in men with premature ejaculation. The etiology of premature ejaculation is currently considered psychological in nature. However, the possibility that urologic, hormonal, or neurologic factors may contribute to this condition should be considered in its management.

METHODS

We evaluated segmented urine specimens before and after prostatic massage and expressed prostatic secretion specimens from 46 patients with premature ejaculation and 30 controls by bacteriologic localization studies. The incidence of premature ejaculation in the subjects with chronic prostatitis was also evaluated.

RESULTS

Prostatic inflammation was found in 56.5% and chronic bacterial prostatitis in 47.8% of the subjects with premature ejaculation, respectively. When compared with the controls, these novel findings were statistically significant (P <0.05).

CONCLUSIONS

Considering the role of the prostate gland in the mechanism of ejaculation, we suggest a role for chronic prostate inflammation in the pathogenesis of some cases of premature ejaculation. Since chronic prostatitis has been found with a high frequency in men with premature ejaculation, we stress the importance of a careful examination of the prostate before any pharmacologic or psychosexual therapy for premature ejaculation.

Gamma-ray emission concurrent with the nova in the symbiotic binary V407 Cygni

Novae are thermonuclear explosions on a white dwarf surface fueled by mass accreted from a companion star. Current physical models posit that shocked expanding gas from the nova shell can produce x-ray emission, but emission at higher energies has not been widely expected. Here, we report the Fermi Large Area Telescope detection of variable gamma-ray emission (0.1 to 10 billion electron volts) from the recently detected optical nova of the symbiotic star V407 Cygni. We propose that the material of the nova shell interacts with the dense ambient medium of the red giant primary and that particles can be accelerated effectively to produce pi(0) decay gamma-rays from proton-proton interactions. Emission involving inverse Compton scattering of the red giant radiation is also considered and is not ruled out.

Lack of sexual activity from erectile dysfunction is associated with a reversible reduction in serum testosterone

The role of androgenic hormones in human sexuality, in the mechanism of erection and in the pathogenesis of impotence is under debate. While the use of testosterone is common in the clinical therapy of male erectile dysfunction, hypogonadism is a rare cause of impotence. We evaluated serum testosterone levels in men with erectile dysfunction resulting either from organic or non-organic causes before and after non-hormonal impotence therapy. Eighty-three consecutive cases of impotence (70% organic, 30% non-organic, vascular aetiology being the most frequent) were subjected to hormonal screening before and after various psychological, medical (prostaglandin E1, yohimbine) or mechanical therapies (vascular surgery, penile prostheses, vacuum devices). Thirty age-matched healthy men served as a control group. Compared to controls, patients with impotence resulting from both organic and non-organic causes showed reduced serum levels of both total testosterone (11.1 +/- 2.4 vs. 17.7 +/- 5.5 nmol/L) and free testosterone (56.2 +/- 22.9 vs. 79.4 +/- 27.0 pmol/L) (both p < 0.001). Irrespective of the different aetiologies and of the various impotence therapies, a dramatic increase in serum total and free testosterone levels (15.6 +/- 4.2 nmol/L and 73.8 +/- 22.5 pmol/L, respectively) was observed in patients who achieved normal sexual activity 3 months after commencing therapy (p < 0.001). On the contrary, serum testosterone levels did not change in patients in whom therapies were ineffective. Since the pre-therapy low testosterone levels were independent of the aetiology of impotence, we hypothesize that this hormonal pattern is related to the loss of sexual activity, as demonstrated by its normalization with the resumption of coital activity after different therapies. The corollary is that sexual activity may feed itself throughout the increase in testosterone levels.

The effects of iodoprophylaxis on thyroid size during pregnancy

Thyroid gland size was ultrasonographically determined in 35 pregnant women who live in an area with moderate iodine deficiency. Iodide salt was administered to group A (n = 17), whereas group B (n = 18) was used as a control. Each group was tested for thyroid-stimulating hormone serum levels, iodine excretion, and thyroid volume. In both groups thyroid-stimulating hormone levels were similar and did not change throughout pregnancy. The iodine excretion at the third trimester in the treated group was significantly (p less than 0.01) higher than that of group B (100.0 +/- 39.0 versus 50.0 +/- 37.0 micrograms iodine per 24 hours, respectively). Initially, thyroid volume did not differ between the two groups. At the end of pregnancy, no difference was found in thyroid size in group A, whereas in the untreated women it increased significantly (p less than 0.0001) with a mean increase of 1.6 +/- 0.6 ml (16.2% +/- 6.0%). These results show that the increased thyroid size in the control group was mainly a result of relative iodine deficiency and that iodoprophylaxis should be warranted even in areas with moderate iodine deficiency to prevent the increase in thyroid size and, probably, to avoid the risk of maternal and fetal hypothyroidism.

Management of syncope referred urgently to general hospitals with and without syncope units

OBJECTIVE

We tested the hypothesis that management of patients with syncope admitted urgently to a general hospital may be influenced by the presence of an in-hospital structured syncope unit.

BACKGROUND

The management of syncope is not standardized. Methods We compared six hospitals equipped with a syncope unit organized inside the department of cardiology with six matched hospitals without such facilities. The study enroled all consecutive patients referred to the emergency room from 5 November 2001 to 7 December 2001 who were affected by transient loss of consciousness as their principal symptom.

RESULTS

There were 279 patients in the syncope unit hospitals and 274 in the control hospitals. In the study group, 30 (11%) patients were referred to the syncope unit for evaluation. In the study group, 12% fewer patients were hospitalized (43 vs 49%, not significant) and 8% fewer tests were performed (3.3+/-2.2 vs 3.6+/-2.2 per patient, not significant). In particular, the study group patients underwent fewer basic laboratory tests (75 vs 86%, P=0.002), fewer brain-imaging examinations (17 vs 24%, P=0.05), fewer echocardiograms (11 vs 16%, P=0.04), more carotid sinus massage (13 vs 8%, P=0.03) and more tilt testing (8 vs 1%, P=0.000). In the study group, there was a +56% rate of final diagnosis of neurally mediated syncope (56 vs 36%, P=0.000).

CONCLUSION

Although only a minority of patients admitted as an emergency are referred to the syncope unit, overall management is substantially affected. It is speculated that the use of a standardized approach, such as that typically adopted in the syncope unit, is able to influence overall practice in the hospital.

A comparison of peak sputum tobramycin concentration in patients with cystic fibrosis using jet and ultrasonic nebulizer systems. Aerosolized Tobramycin Study Group

STUDY OBJECTIVE

To determine whether adequate concentrations of a new formulation of tobramycin could be delivered to the lower respiratory tract of patients with cystic fibrosis (CF) using a jet nebulizer delivery system.

DESIGN

A multicenter, open-label, randomized, crossover study.

SETTING

Ten tertiary care, university-affiliated, teaching hospitals in the United States.

PATIENTS AND CONTROL SUBJECTS

Sixty-eight patients recruited from 10 CF Foundation centers and who were at least 8 years of age, had a diagnosis of CF, and expectorated daily sputum. No control subjects enrolled.

INTERVENTIONS

Each patient received one administration of aerosolized tobramycin from each of the three nebulizer systems in random order. Each administration was separated by a minimum of 48 h. The two jet nebulizer systems tested were the Sidestream (Medic-Aid; Sussex, UK), and the Pari LC (Pari Respiratory Equipment; Richmond, Va), with a DeVilbiss Pulmoaide compressor (DeVilbiss Health Care; Somerset, Pa), both administering 300 mg tobramycin in 5 mL of 1/4 normal saline solution (NS). Patients were also administered 600 mg tobramycin in 30 mL of 1/2 NS with the UltraNeb 99/100 (DeVilbiss).

MEASUREMENTS

Sputum and serum tobramycin concentration and pulmonary function were monitored. An adequate peak sputum tobramycin concentration was defined as > 128 microg/g sputum at any of three time points (10, 60, or 120 min) after completion of treatments.

RESULTS

The peak tobramycin concentrations in expectorated sputum were 687+/-663 microg/g (mean+/-SD) with the Pari LC and 489+/-402 microg/g with the Sidestream. Adequate peak sputum tobramycin concentration was achieved in 93% of the patients with the Sidestream, and in 87% of the patients with the Pari LC. Peak sputum concentrations were found to be substantially higher when patients received tobramycin administered with the UltraNeb 99/100, 1,498+/-1,331 microg/g with 30% of patients having levels exceeding 2,000 microg/g. Serum tobramycin concentrations were < or = 4 microg/mL for all patients following administration with each nebulizer.

CONCLUSIONS

Adequately high sputum tobramycin concentrations were documented in sputum in > 85% of patients following the administration of 300 mg/5 mL formulation of tobramycin aerosolized by the two jet nebulizer delivery systems, Sidestream and Pari LC. The single tobramycin administration delivered by these two systems is well-tolerated.

The Fermi Gamma-Ray Space Telescope discovers the pulsar in the young galactic supernova remnant CTA 1

Energetic young pulsars and expanding blast waves [supernova remnants (SNRs)] are the most visible remains after massive stars, ending their lives, explode in core-collapse supernovae. The Fermi Gamma-Ray Space Telescope has unveiled a radio quiet pulsar located near the center of the compact synchrotron nebula inside the supernova remnant CTA 1. The pulsar, discovered through its gamma-ray pulsations, has a period of 316.86 milliseconds and a period derivative of 3.614 x 10(-13) seconds per second. Its characteristic age of 10(4) years is comparable to that estimated for the SNR. We speculate that most unidentified Galactic gamma-ray sources associated with star-forming regions and SNRs are such young pulsars.

Detection of high-energy gamma-ray emission from the globular cluster 47 Tucanae with Fermi

We report the detection of gamma-ray emissions above 200 megaelectron volts at a significance level of 17sigma from the globular cluster 47 Tucanae, using data obtained with the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope. Globular clusters are expected to emit gamma rays because of the large populations of millisecond pulsars that they contain. The spectral shape of 47 Tucanae is consistent with gamma-ray emission from a population of millisecond pulsars. The observed gamma-ray luminosity implies an upper limit of 60 millisecond pulsars present in 47 Tucanae.

Graft-versus-host disease prevention by methotrexate combined with cyclosporin compared to methotrexate alone in patients given marrow grafts for severe aplastic anaemia: long-term follow-up of a controlled trial

Forty-six patients with aplastic anaemia (median age 23 years) were given cyclophosphamide followed by infusion of marrow from an HLA-identical family member. To evaluate postgrafting prophylaxis for graft-versus-host disease (GVHD), the patients were entered into a randomized prospective trial comparing a combination of methotrexate and cyclosporin (n = 22) to methotrexate alone (n = 24). Methotrexate/cyclosporin significantly reduced the incidence and severity of acute GVHD and improved early survival. This report updates the results of the randomized trial with followup ranging from 3 to more than 6 years. The methotrexate/cyclosporin regimen did not interfere with sustained engraftment, and there were no significant differences in the incidence of early or late graft rejection among the two treatment groups (10% v 4%). The incidence of chronic GVHD was higher among methotrexate/cyclosporin-treated patients (58% v 36%; P = 0.18). Two patients in each treatment group still require treatment for chronic GVHD, while treatment is no longer needed in the other patients. Projected 4-year survival is 73% in patients given methotrexate/cyclosporin compared to 58% in patients given methotrexate alone (P = 0.16). Having achieved a reduction in the incidence of acute GVHD and associated early mortality without impairing engraftment, it is clear that future progress in marrow grafting for aplastic anaemia must come in the area of chronic GVHD.

Incorporating the time dimension in receiver operating characteristic curves: a case study of prostate cancer

Early diagnosis of disease has potential to reduce morbidity and mortality. Biomarkers may be useful for detecting disease at early stages before it becomes clinically apparent. Prostate-specific antigen (PSA) is one such marker for prostate cancer. This article is concerned with modeling receiver operating characteristic (ROC) curves associated with biomarkers at various times prior to the time at which the disease is detected clinically, by two methods. The first models the biomarkers statistically using mixed-effects regression models, and uses parameter estimates from these models to estimate the time-specific ROC curves. The second directly models the ROC curves as a function of time prior to diagnosis and may be implemented using software packages with binary regression or generalized linear model routines. The approaches are applied to data from 71 prostate cancer cases and 71 controls who participated in a lung cancer prevention trial. Two biomarkers for prostate cancer were considered: total serum PSA and the ratio of free to total PSA. Not surprisingly, both markers performed better as the interval between PSA measurement and clinical diagnosis decreased. Although the two markers performed similarly eight years prior to diagnosis, it appears that total PSA performed better than the ratio measure at times closer to diagnosis. The area under the ROC curve was consistently greater for total PSA than for the ratio four and two years prior to diagnosis and at the time of diagnosis.

Detecting chlorophyll, Secchi disk depth and surface temperature in a sub-alpine lake using Landsat imagery

Some bio-physical parameters, such as chlorophyll a concentration, Secchi disk depth and water surface temperature were mapped in the sub-alpine Lake Iseo (Italy) using Landsat Thematic Mapper (TM) data acquired on the 7 March 1997. In order to adequately investigate the water-leaving radiance, TM data were atmospherically corrected using a partially image-based method, and the atmospheric transmittance was measured in synchrony with the satellite passage. An empirical approach of relating atmospherically corrected TM spectral reflectance values to in situ measurements, collected during the satellite data acquisition, was used. The models developed were used to map the chlorophyll concentration and Secchi disk depth throughout the lake. Both models gave high determination coefficients (R2 = 0.99 for chlorophyll and R2 = 0.85 for the Secchi disk) and the spatial distribution of chlorophyll concentration and Secchi disk depth was mapped with contour intervals of 1 mg/m3 and 1 m, respectively. A scene-independent procedure was used to derive the surface temperature of the lake from the TM data with a root mean square error of 0.3 degrees C.

Improvement in rejection, engraftment rate and survival without increase in graft-versus-host disease by high marrow cell dose in patients transplanted for aplastic anaemia

Two hundred and fifty-two consecutive patients with severe aplastic anaemia were conditioned by cyclophosphamide and given marrow transplants from HLA-identical siblings or parents. The results were analysed to examine the influence of marrow cell dose on graft rejection, speed of engraftment, survival and acute and chronic graft-versus-host disease (GVHD). Sixty patients received a corrected marrow cell dose below 2.2 x 10(8) nucleated cells per kg body weight, 73 patients between 2.2 and 3.2 x 10(8) cells/kg, 60 patients between 3.3 and 4.2 x 10(8) cells/kg, and 59 patients more than 4.2 x 10(8) cells/kg. The significant association between high marrow cell dose and low risk of graft rejection previously reported was confirmed. In addition, high marrow cell dose resulted in small but statistically significant reductions in time to granulocyte and platelet recoveries in patients with sustained engraftment. High marrow cell dose was also associated with a significant improvement in patient survival, a result solely due to the reduction in the incidence of graft rejection. Neither acute nor chronic GVHD were influenced by marrow cell dose. We conclude that the maximum marrow cell dose should be transplanted in patients with severe aplastic anaemia. Maximum marrow cell doses are likely to decrease the incidence of graft rejection, shorten the time to engraftment thereby decreasing the need for blood products and antibiotic support, and improve overall patient survival.

Sexual inactivity results in reversible reduction of LH bioavailability

We have recently documented significantly reduced serum testosterone (T) levels in patients with erectile dysfunction (ED). To understand the mechanism of this hypotestosteronemia, which was independent of the etiology of ED, and its reversibility only in patients in whom a variety of nonhormonal therapies restored sexual activity, we measured serum luteinizing hormone (LH) in the same cohort of ED patients (n=83; 70% organic, 30% nonorganic). Both immunoreactive LH (I-LH) and bioactive LH (B-LH) were measured at entry and 3 months after therapy. Based on outcome (ie number of successful attempts of intercourse per month), patients were categorized as full responders (namely, at least eight attempts; n=51), partial responders (at least one attempt; n=20) and non-responders (n=16). Compared to 30 healthy men with no ED, baseline B-LH (mean+/-s.d.) in the 83 patients was decreased (13.6+/-5.5 vs 31.7+/-6.9 IU/L, P<0.001), in the face of a slightly increased, but in the normal range, I-LH (5.3+/-1.8 vs 3.4+/-0.9 IU/L, P<0.001); consequently, the B/I LH ratio was decreased (3.6+/-3.9 vs 9.7+/-3.3, P<0.001). Similar to our previous observation for serum T, the three outcome groups did not differ significantly for any of these three parameters at baseline. However, outcome groups differed after therapy. Bioactivity of LH increased markedly in full responders (pre-therapy=13.7+/-5.3, post-therapy=22.6+/-5.4, P<0.001), modestly in partial responders (14.8+/-6.9 vs 17.2+/-7.0, P<0.05) but remained unchanged in non-responders (11.2+/-2.2 vs 12.2+/-5.1). The corresponding changes went in the opposite direction for I-LH (5.2+/-1.7 vs 2.6+/-5.4, P<0.001; 5.4+/-2.2 vs 4.0+/-1.7, P<0.05; 5.6+/-1.2 vs 5.0+/-1.2, respectively), and in the same direction as B-LH for the B/I ratio (3.7+/-4.1 vs 11.8+/-7.8, P<0.001; 4.2+/-4.3 vs 5.8+/-4.2, P<0.05; 2.1+/-0.7 vs 2.6+/-1.3, respectively). We hypothesize that the hypotestosteronemia of ED patients is due to impaired bioactivity of LH. This reduced bioactivity is reversible, provided that resumption of sexual activity is achieved regardless of the therapeutic modality. Because biopotency of pituitary hormones is controlled by the hypothalamus, LH hypoactivity should be due to the hypothalamic functional damage associated to the psychological disturbances which unavoidably follow sexual inactivity.

Advances and Perspectives in Tissue Culture and Genetic Engineering of Cannabis

For a long time, Cannabis sativa has been used for therapeutic and industrial purposes. Due to its increasing demand in medicine, recreation, and industry, there is a dire need to apply new biotechnological tools to introduce new genotypes with desirable traits and enhanced secondary metabolite production. Micropropagation, conservation, cell suspension culture, hairy root culture, polyploidy manipulation, and Agrobacterium-mediated gene transformation have been studied and used in cannabis. However, some obstacles such as the low rate of transgenic plant regeneration and low efficiency of secondary metabolite production in hairy root culture and cell suspension culture have restricted the application of these approaches in cannabis. In the current review, in vitro culture and genetic engineering methods in cannabis along with other promising techniques such as morphogenic genes, new computational approaches, clustered regularly interspaced short palindromic repeats (CRISPR), CRISPR/Cas9-equipped Agrobacterium-mediated genome editing, and hairy root culture, that can help improve gene transformation and plant regeneration, as well as enhance secondary metabolite production, have been highlighted and discussed.