Association between the presence of protein bands in ram seminal plasma and sperm tolerance to freezing.

This study evaluated associations between the presence of protein bands in ram seminal plasma and the quality of sperm frozen with distinct extenders. Ejaculates were frozen in a Tris-egg yolk based extender, including either 5% glycerol or 100mM trehalose. Seminal plasma samples were submitted to unidimensional electrophoresis. Pre-freezing and post-thawing sperm quality was similar between extenders (P>0.05). A total of 26 bands were identified in ram seminal plasma. Pre-freezing sperm motility was increased when the 15, 19 and 80kDa bands were present in seminal plasma (P<0.05). The presence of an 11kDa band in seminal plasma was associated with reduced pre-freezing membrane integrity (P<0.05). After thawing, both sperm motility and membrane integrity were reduced when a 24kDa band was present in seminal plasma (P<0.05). Post-thawing acrosome integrity was greater in the presence of a 31kDa band in seminal plasma (P<0.05). Regardless of the cryoprotectant included in the freezing extender, these six bands may be potential markers for ram sperm tolerance to freezing.

Ultrafast x-ray scattering of xenon nanoparticles: imaging transient states of matter.

Femtosecond x-ray laser flashes with power densities of up to 10(14) W/cm(2) at 13.7 nm wavelength were scattered by single xenon clusters in the gas phase. Similar to light scattering from atmospheric microparticles, the x-ray diffraction patterns carry information about the optical constants of the objects. However, the high flux of the x-ray laser induces severe transient changes of the electronic configuration, resulting in a tenfold increase of absorption in the developing nanoplasma. The modification in opaqueness can be correlated to strong atomic charging of the particle leading to excitation of Xe(4+). It is shown that single-shot single-particle scattering on femtosecond time scales yields insight into ultrafast processes in highly excited systems where conventional spectroscopy techniques are inherently blind.

Infected Viabahn stent graft in the superficial femoral artery.

We present a case of an infected stent graft in the superficial femoral artery (SFA). A 67-year-old woman underwent excision of an infected Viabahn stent graft. At exploration there was no apparent artery around the majority of the stent graft, suggesting that the SFA had been autolysed. Infected stents and stent grafts are rare in the SFA position. The risk of infection is likely minimised with standard treatments including drainage of infection prior to stent graft placement and periprocedural antibiotic administration. Successful management will, in most cases, require excision of the stent graft and adjunctive arterial reconstruction, as necessary.

Investigations of dengue-2 susceptibility and body size among Aedes aegypti populations.

The mosquito Aedes aegypti (L.) (Diptera: Culicidae) is the primary global vector for dengue virus (DENV), yet considerable genetic variation exists among populations in terms of its competence to vector DENV. Variability in adult body size has also been observed among various mosquito populations and several studies have reported a relationship between body size and arbovirus dissemination, although most of these relied on artificially derived variation in body size. Here we examine the relationship between body size and disseminated DENV infection among 10 Ae. aegypti populations reared under optimum laboratory conditions. Body size variability was inferred from wing length measurements and DENV competence was evaluated as the proportion of individuals with disseminated infections following exposure to the dengue-2 JAM1409 strain. There were significant differences in mean wing lengths among populations (anova, F(9,22)= 7.10, P < 0.0001), ranging from 2.16 mm (Bangkok population) to 2.79 mm (MOYO-S [susceptible] population). We also observed significant differences among some populations in mean DENV infection rates (Waller-Duncan K-ratio t-test), ranging from 19.54% (MOYO-R [refractory] population) to 56.60% (MOYO-S population). However, we did not observe evidence for significant interactions between body size and DENV dissemination. We suggest that either the two traits are genetically independent or that our ability to detect interactions between them was limited by their respective inheritances as quantitative traits.

Soft x-ray laser spectroscopy on trapped highly charged ions at FLASH.

In a proof-of-principle experiment, we demonstrate high-resolution resonant laser excitation in the soft x-ray region at 48.6 eV of the 2 (2)S(1/2) to 2 (2)P(1/2) transition of Li-like Fe23+ ions trapped in an electron beam ion trap by using ultrabrilliant light from Free Electron Laser in Hamburg (FLASH). High precision spectroscopic studies of highly charged ions at this and upcoming x-ray lasers with an expected accuracy gain up to a factor of a thousand, become possible with our technique, thus potentially yielding fundamental insights, e.g., into basic aspects of QED.

Amorphouslike diffraction pattern in solid metallic titanium.

Amorphouslike diffraction patterns of solid elemental titanium have been detected under high pressure and high temperature using in situ energy-dispersive x-ray diffraction and a multianvil press. The onset pressure and the temperature of formation of amorphous titanium is found to be close to the alpha-beta-omega triple point in the P-T phase diagram. Amorphous Ti has been found to be thermally stable up to 1250 degrees C for at least 3 min at some pressures. By analyzing the conditions for producing amorphous elemental Zr and Ti, we observed a multi-phase-point amorphization phenomenon for preparing single-element bulk amorphous metals. The results reported may open a new way to preparing single-element bulk amorphous metals with a high thermal stability.

Prevalence of retinopathy in Caucasian type 2 diabetic patients from the South of Brazil and relationship with clinical and metabolic factors.

Diabetic retinopathy (DR) is a sight-threatening chronic complication of diabetes mellitus and is the leading cause of acquired blindness in adults. In this cross-sectional study, we investigated the prevalence of and the factors associated with DR in an analysis of 210 consecutive and unrelated Brazilian Caucasians with type 2 diabetes mellitus. Retinopathy was evaluated by ophthalmoscopy and/or biomicroscopy through dilated pupils. The relationship between clinical and metabolic variables and the presence of DR was assessed by logistic regression analysis. DR was detected in 99 of the 210 patients (47%). In the univariate logistic regression analyses, male sex, duration of diabetes, body mass index, glycated hemoglobin, C-peptide, LDL cholesterol, smoking, and albumin excretion rate were found to be associated with the presence of DR. However, the multiple logistic regression analysis showed that only duration of diabetes (odds ratio (OR) = 1.15, 95% CI = 1.09-1.22; P < 0.001), glycated hemoglobin (OR = 1.21, 95% CI = 1.01-1.46; P = 0.047) and albumin excretion rate > 100 microg/min (OR = 12.72, 95% CI = 3.89-41.56; P < 0.001) were independently associated with DR. Although DR was found to be frequent among Brazilian type 2 diabetic patients, its prevalence was within the range observed in other Caucasian populations. Our findings emphasize the need for good glycemic control in order to prevent or delay the onset of DR, since the most well-known risk factors for the development of this complication in type 2 diabetes mellitus, such as duration of diabetes, glycated hemoglobin and albumin excretion rate were independently related to DR.

Prevalence of retinopathy in Caucasian type 2 diabetic patients from the South of Brazil and relationship with clinical and metabolic factors

Diabetic retinopathy (DR) is a sight-threatening chronic complication of diabetes mellitus and is the leading cause of acquired blindness in adults. In this cross-sectional study, we investigated the prevalence of and the factors associated with DR in an analysis of 210 consecutive and unrelated Brazilian Caucasians with type 2 diabetes mellitus. Retinopathy was evaluated by ophthalmoscopy and/or biomicroscopy through dilated pupils. The relationship between clinical and metabolic variables and the presence of DR was assessed by logistic regression analysis. DR was detected in 99 of the 210 patients (47 percent). In the univariate logistic regression analyses, male sex, duration of diabetes, body mass index, glycated hemoglobin, C-peptide, LDL cholesterol, smoking, and albumin excretion rate were found to be associated with the presence of DR. However, the multiple logistic regression analysis showed that only duration of diabetes (odds ratio (OR) = 1.15, 95 percent CI = 1.09-1.22; P < 0.001), glycated hemoglobin (OR = 1.21, 95 percent CI = 1.01-1.46; P = 0.047) and albumin excretion rate >100 µg/min (OR = 12.72, 95 percent CI = 3.89-41.56; P < 0.001) were independently associated with DR. Although DR was found to be frequent among Brazilian type 2 diabetic patients, its prevalence was within the range observed in other Caucasian populations. Our findings emphasize the need for good glycemic control in order to prevent or delay the onset of DR, since the most well-known risk factors for the development of this complication in type 2 diabetes mellitus, such as duration of diabetes, glycated hemoglobin and albumin excretion rate were independently related to DR.

A targeted approach to the identification of candidate genes determining susceptibility to Plasmodium gallinaceum in Aedes aegypti.

The malaria parasite, Plasmodium, has evolved an intricate life cycle that includes stages specific to a mosquito vector and to the vertebrate host. The mosquito midgut represents the first barrier Plasmodium parasites encounter following their ingestion with a blood meal from an infected vertebrate. Elucidation of the molecular interaction between the parasite and the mosquito could help identify novel approaches to preventing parasite development and subsequent transmission to vertebrates. We have used an integrated Bulked Segregant Analysis-Differential Display (BSA-DD) approach to target genes expressed that are in the midgut and located within two genome regions involved in determining susceptibility to P. gallinaceum in the mosquito Aedes aegypti. A total of twenty-two genes were identified and characterized, including five genes with no homologues in public sequence databases. Eight of these genes were mapped genetically to intervals on chromosome 2 that contain two quantitative trait loci (QTLs) that determine susceptibility to infection by P. gallinaceum. Expression analysis revealed several expression patterns, and ten genes were specifically or preferentially expressed in the midgut of adult females. Real-time PCR quantification of expression with respect to the time of blood meal ingestion and infection status in mosquito strains permissive and refractory for malaria revealed a differential expression pattern for seven genes. These represent candidate genes that may influence the ability of the mosquito vector to support the development of Plasmodium parasites. Here we describe their isolation and discuss their putative roles in parasite-mosquito interactions and their use as potential targets in strategies designed to block transmission of malaria.

Leg symptoms in peripheral arterial disease: associated clinical characteristics and functional impairment.

CONTEXT: Persons with lower-extremity peripheral arterial disease (PAD) are often asymptomatic or have leg symptoms other than intermittent claudication (IC). OBJECTIVE: To identify clinical characteristics and functional limitations associated with a broad range of leg symptoms identified among patients with PAD. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional study of 460 men and women with PAD and 130 without PAD, who were identified consecutively, conducted between October 1998 and January 2000 at 3 Chicago-area medical centers. MAIN OUTCOME MEASURES: Ankle-brachial index score of less than 0.90; scores from 6-minute walk, accelerometer-measured physical activity over 7 days, repeated chair raises, standing balance (full tandem stand), 4-m walking velocity, San Diego claudication questionnaire, Geriatric Depression Score Short-Form, and the Walking Impairment Questionnaire. RESULTS: All groups with PAD had poorer functioning than participants without PAD. The following values are for patients without IC vs those with IC. Participants in the group with leg pain on exertion and rest (n = 88) had a higher (poorer) score for neuropathy (5.6 vs 3.5; P<.001), prevalence of diabetes mellitus (48.9% vs 26.7%; P<.001), and spinal stenosis (20.8% vs 7.2%; P =.002). The atypical exertional leg pain/carry on group (exertional leg pain other than IC associated with walking through leg pain [n = 41]) and the atypical exertional leg pain/stop group (exertional leg pain other than IC that causes one to stop walking [n = 90]) had better functioning than the IC group. The group without exertional leg pain/inactive (no exertional leg pain in individual who walks

Carotid endarterectomy in octogenarians: comparison with patient characteristics and outcomes in younger patients.

OBJECTIVES: Carotid endarterectomy has been shown to be of clear benefit to selected patients. However, recent trials of carotid endarterectomy versus best medical therapy have excluded octogenarians, and some authors have suggested that carotid endarterectomy would have an unfavorable cost-benefit relationship in octogenarians. We compared patients and results for carotid endarterectomy in octogenarians and younger patients. METHODS: We reviewed the results for 582 primary carotid endarterectomies (90 in octogenarians and 492 in younger patients) performed in 528 patients between February 1, 1985, and January 31, 1998 (all data were collected prospectively for the most recent 301 carotid endarterectomies). Conventional surgical technique was used with general anesthesia, selective shunting, and selective patching. Main outcome measures were perioperative and late ipsilateral stroke and death. RESULTS: The two groups were similar with respect to indications for carotid endarterectomy and patient characteristics, except that octogenarians were more likely to have histories of congestive heart failure or hypertension and less likely to have histories of smoking or chronic lung disease. Carotid endarterectomy was performed for asymptomatic disease in 27% of the octogenarians and 33% of the younger patients (P =.31). Stenosis was >/=80% in 90% of the octogenarians and 78% of the younger patients (P =.014). Perioperative strokes, all of which were ipsilateral, occurred in one octogenarian (1.1%) and eight younger patients (1.6%, P = 1.00). No octogenarians and two younger patients died within 30 days of surgery (P = 1.00). Length of stay and direct costs associated with carotid endarterectomy were similar for octogenarians and younger patients. Late strokes occurred in two octogenarians (one ipsilateral) and four younger patients (two ipsilateral). Life table estimates of freedom from ipsilateral stroke at 2 years were 98% and 97% for octogenarians and younger patients, respectively (log-rank P =.69), and life table estimates of patient survival at 4 years were 81% and 89% for octogenarians and younger patients, respectively (P =.11). Octogenarians represented an increasing fraction of the carotid endarterectomies performed during the study period. CONCLUSIONS: Octogenarians selected for carotid endarterectomy were similar to younger patients with respect to indications for carotid endarterectomy and comorbidities. Early mortality, early and late neurologic outcome, complications, and resource utilization were similar for the two groups, and more than 75% of octogenarians survived 4 years after undergoing carotid endarterectomy. Cost-benefit analyses for carotid endarterectomy, which are highly sensitive to expected patient survival, might not be pertinent to individual patient situations. Intellectually intact octogenarians without unusually severe comorbidities are good candidates for and should be offered the benefits of carotid endarterectomy.

Assessment of coagulation system activation using spot urine measurements.

Coagulation system activation is most commonly assessed by measuring levels of one or more proteins in peripheral blood. Because faulty blood-drawing can cause activation of the coagulation system, artifactual elevations of such markers have been reported. We have therefore investigated the possibility of using randomly collected ('spot') urine samples as a non-invasive means of assessing the state of coagulation system activation. Using a commercially available enzyme-linked immunosorbent assay kit designed to measure plasma levels of fragment 1 + 2, we found immunoreactive fragment 2 in healthy control subjects, and significantly increased levels in diabetic and non-diabetic pregnant subjects, and patients with venous thromboembolism, prostate cancer, and diabetes. Measurements of excretion of immunoreactive fragment 2 are worth further study as an adjunct or alternative to plasma-based assays designed to detect or quantify coagulation system activation.

The pre-conditioning incidence of antiphospholipid antibodies is not significantly increased in patients with bone marrow transplant-related organ dysfunction.

Hepatic dysfunction resulting from hepatic veno-occlusive disease (VOD) is a common complication of bone marrow transplantation (BMT). Some investigators believe that hepatic dysfunction, along with pulmonary and central nervous system (CNS) dysfunction, is part of a systemic disorder called multiple organ dysfunction syndrome (MODS). Endothelial damage by pretransplant chemo-radiation and activation of hemostasis are considered early events in the development of hepatic VOD. The pathological mechanism leading to fibrous obliteration of hepatic vessels may also take place in pulmonary and CNS vessels. Since antiphospholipid antibodies (aPA) are associated with venous and arterial thrombosis, which can lead to vessel occlusion, we asked if the incidence of aPA before conditioning was greater in patients who developed MODS following BMT. Samples drawn before pretransplant chemo-radiation from 57 patients who subsequently developed MODS and 55 control patients who did not develop MODS were studied blindly for aPA by ELISA. The number of aPA-positive patients who developed MODS (10/57), compared to the number of aPA-positive patient controls who did not develop MODS (7/55) was not statistically significant (P = 0.48). Our data indicate that the incidence of aPA before conditioning was not greater in patients who developed MODS, including hepatic VOD, following BMT.

Which asymptomatic patients should have carotid endarterectomy?

Carotid endarterectomy for asymptomatic very-high-grade stenosis has been shown to be of clear benefit when compared with best medical treatment in recent prospective randomized studies. However, the benefit of carotid endarterectomy in these trials has been less than most vascular surgeons predicted based on prior nonrandomized studies. Furthermore, vascular surgeons often see patients who do not fit the inclusion criteria for any of the prospective randomized trials and whose potential benefit from endarterectomy may be different from that observed in those trials. Medical comorbidities or other patient characteristics that suggest even small increases in risk for carotid endarterectomy may negate the marginal benefit of the procedure in asymptomatic patients. Potential benefit is also highly dependent on surgeon-specific and hospital-specific perioperative morbidity and mortality. This article addresses some of the factors that may alter the potential benefit of carotid endarterectomy and the implications with respect to recommendations for or against carotid endarterectomy in the individual patient.