Heat-Induced Hyperactivation

Purpose: The objectives of this study were (1) to determine the sperm hyperactivation and related kinematic parameters at 40°C after using four sperm wash procedures and (2) to correlate the heat-induced hyperactivation data with cases of clinical pregnancies from either artificial insemination or standard in vitro fertilization (IVF). Methods: Semen samples (n = 51) were collected by ejaculation, and semen analyses were carried out to determine the pretreatment data. Sperm kinematic measurements were performed using the Hamilton Thorn HTM-C computer-aided sperm analyzer. Hyperactivation was determined using the sort module on the HTM-C. Membrane integrity was assessed using the hypoosmotic sperm swelling procedure. Sperm morphology and acrosomal status were also determined using the Spermac stain. Each semen specimen was divided and processed through either the swim-up wash, the 1-h test-yolk buffer (TYB) wash, the 1 mg/ml pentoxifylline stimulant procedure, or the two-layer 90:47% gradient colloidal solution procedure. The washed sperm were incubated at 25 or at 40° C for 4 hr. After incubation, kinematic parameters were assessed for the posttreatment data. Semen specimens were obtained on different occasions for artificial insemination or standard IVF. Data from intracytoplasmic sperm injection cases were not included to avoid confounding factors. Live births and/or pregnancies with fetal heartbeat examined by ultrasound were considered clinical pregnancies. Results: Heat-induced hyperactive motility was significantly higher in sperm of the male partner of pregnant (n = 7) patients compared with nonpregnant (n = 44) patients (mean ± SE, 10.0 ± 3.3 versus 5.5 ± 0.8%) after TYB processing fallowed by 4 hr of incubation at 40°C. This was also observed after colloid (Percoll) processing (11.6 ± 4.6 versus 5.8 ± 0.8%). There were no differences in hyperactivation after 4 hr at 23°C between pregnant and nonpregnant cases. Parameters such as count, volume, motility, viability, and acrosomal status were not different for the groups. However, the percentage of sperm with normal morphology (WHO classification) was twice as high in the pregnant group versus the nonpregnant group. Conclusions: Heat-induced hyperactivation was associated with fertile sperm and was predictive of pregnancy obtained after artificial insemination or IVF. The association was evident only after TYB or Percoll sperm processing. The study could not confirm the finding of significant decreases in motility after heat treatment of sperm derived from infertile males. The mechanism for heat-induced hyperactivation did not involve membrane integrity or the sperm acrosome, although an involvement of heat shock proteins was postulated. Interestingly, there were no pregnancies when sperm did not exhibit heat-induced hyperactivation.     

Adverse effects of increased body weight on quantitative measures of mammographic image quality

OBJECTIVE: The purpose of our study was to show that compressed breast thickness on mammograms in overweight and obese women exceeds the thickness in normal-weight women and that increased thickness results in image degradation. SUBJECTS AND METHODS: Three hundred consecutive routine mammograms were reviewed. Patients were categorized according to body mass index. Compression thickness, compressive force, kilovoltage, and milliampere-seconds were recorded. Geometric unsharpness and contrast degradation were calculated for each body mass index category. RESULTS: Body mass index categories were lean (3%), normal (36%), overweight (36%), and obese (25%). Body mass index was directly correlated with compressed thickness. In the mediolateral oblique view, the mean thickness of the obese category exceeded normal thickness by 18 mm (p < 0.01), corresponding to a 32% increase in geometric unsharpness. Mean obese thickness exceeded lean thickness by 33 mm (p < 0.01), corresponding to a 79% increase in unsharpness. Similar trends were observed for the craniocaudal view. In the mediolateral oblique projection, there was an increase of 1.0 kVp (p < 0.01) for obese compared with normal and 1.7 kVp (p < 0.01) between lean and obese, corresponding, respectively, to a 16% and a 25% decrease in image contrast because of scatter and kilovoltage changes. Milliampere-seconds increased by 47% on the mediolateral oblique images in the obese category compared with normal body mass index. CONCLUSION: An increased body mass index was associated with greater compressed breast thickness, resulting in increased geometric unsharpness, decreased image contrast, and greater potential for motion unsharpness.     

Esophageal atresia and tracheal stenosis: use of three-dimensional CT and virtual bronchoscopy in neonates, infants, and children

OBJECTIVE: The objective of this study was to evaluate the use of three-dimensional CT and virtual bronchoscopy in the treatment of neonates, infants, and children with esophageal atresia and tracheal stenosis. CONCLUSION: Long-gap (n = 1) and short-gap (n = 5) esophageal atresia, long-segment stenosis (n = 2), patent poststenting trachea (n = 1), normal trachea without fistula (n = 1), and tracheal bronchus (n = 1) were studied. Fistulas between the lower esophagus and carina were noted in all six cases of esophageal atresia. All CT findings correlated with operative or bronchoscopy findings. Sensitivity and specificity were 100%. Three-dimensional CT and virtual bronchoscopy are accurate and useful techniques in the preoperative assessment of esophageal atresia and tracheal stenosis in neonates, infants, and children.     

NSAID-induced peptic ulcers and Helicobacter pylori infection: implications for patient management.

The conflicting data about the influence of Helicobacter pylori infection on the ulcer risk in patients receiving NSAIDs can be accounted for by the heterogeneity of study designs and the diversified host response to H. pylori. Factors that will affect the outcome include the choice of H. pylori diagnostic tests, previous ulcer complications, concurrent use of acid suppressants, NSAID-naive versus long-term users, low-dose aspirin (acetylsalicylic acid) versus non-aspirin NSAIDs and whether the result was derived from a pre-specified endpoint or post hoc subgroup analysis. Current evidence suggests that H. pylori eradication reduces the ulcer risk for patients who are about to start receiving NSAIDs but not for those who are already on long-term NSAID therapy. Since treatment with a proton pump inhibitor (PPI) worsens H. pylori-associated corpus gastritis, H. pylori should be tested for, and eradicated if present, before starting long-term prophylaxis with PPIs. Patients with H. pylori infection and a history of ulcer complications who require NSAIDs should receive concomitant PPIs or misoprostol after curing the infection. Among patients receiving low-dose aspirin, who have H. pylori infection and previous ulcer complications, long-term treatment with a PPI further reduces the risk of complicated ulcers if H. pylori eradication fails or if patients use concomitant non-aspirin NSAIDs. Current data on the gastric safety of COX-2 selective NSAIDs in H. pylori-infected patients are conflicting. Limited data suggest that the gastroduodenal sparing effect of rofecoxib is negated by H. pylori infection in patients who have had prior upper gastrointestinal events. In light of potential cardiovascular risk with COX-2 selective NSAIDs, it is important to weigh the potential adverse effects against the benefits for an individual patient.     

Influence of respiration and portal pressure on transabdominal duplex Doppler ultrasound measurement of portal blood flow: a porcine model for experimental studies

Transabdominal duplex Doppler ultrasonography (TDDU) is commonly used for measuring hepatic blood flow (HBF) in clinical practice. Flow velocity and the cross-sectional area (CSA) of vessels are obtained separately and used to compute blood flow. Respiration and changes in portal pressure are known to cause variations in the CSA of the portal vein, but the impact of these parameters on TDDU measurement of portal blood flow is unclear. Eight Yorkshire pigs (20.7-25.1 kg) were used for the study. TDDU determination of portal blood flow was carried out using CSA of the portal vein obtained at inspiration (maximal) and at expiration (minimal) for computation, and the differences obtained were compared. Determination of HBF was carried out simultaneously on the same animals using diisopropyliminodiacetic acid (DISIDA) clearance. A physiological increase in portal pressure was then created by 50% hepatectomy and TDDU measurement similarly carried out on the second postoperative day. Computing portal blood flow in the intact liver using maximal and minimal CSA gave rise to a mean difference of 7.0 ml kg(-1) min(-1) (P < 0.001). A significant correlation was obtained between HBF and portal flow computed from maximal CSA (Pearson's correlation = 0.85, P < 0.033). The respiratory index of the portal vein (maximal CSA/minimal CSA) decreased from 1.5 to 1.2 after hepatectomy, which also caused a 90% increase in portal pressure. Respiration and portal pressure thus significantly impact on TDDU determination of HBF, and in this porcine model, computation using maximal CS more accurately reflects HBF.     

The use of an ambulatory,automatic sleep recording device (QUISI™ Version 1.0) in the evaluation of primary snoring and obstructive sleep apnoea

The use of an ambulatory, automatic sleep recording device (QUISI? Version 1.0) in the evaluation of primary snoring and obstructive sleep apnoea Electroencephalogram (EEG) evaluation with polysomnography (PSG) according to the Rechtschaffen & Kales (R&K) rules is time and cost consumptive, but ambulatory polygraphy systems do not allow EEG recording routinely. As a consequence, the number of sleep disordered events cannot be calculated exactly. QUISI is a one‐channel, self‐applicable ambulatory EEG recording device. The present study was designed as a prospective, non‐randomized clinical trial. This investigation evaluated the results of 40 patients with primary snoring and obstructive sleep apnoea measured with level 1 PSG and QUISI simultaneously. Fifteen patients (37.5%) were primary snorers with normal sleep profiles, whereas 25 patients (62.5%) suffered from obstructive sleep apnoea (OSA) with a Respiratory Disturbance Index (RDI) of 38.6 ± 23.8. The mean total sleeping time (TST) was underestimated by 4.5%, while Sleep Efficiency Index (SEI) was understimated by 4.6% by the QUISI device compared with PSG. The correlation between the QUISI and the PSG estimates for single sleep stages demonstrated only moderate correlation. The statistical significance for sleep stage 2 was r = 0.42, P = 0.002; for sleep stage 3/4, r = 0.31, P = 0.02; and for WAKE, r = 0.33, P = 0.01. Sleep stage 2 as well as sleep stage 3/4 were underestimated by QUISI substantially (difference: ?5.6% and ?10.3%), while WAKE was overestimated by QUISI to a larger amount (difference: +10.4%). Sensitivity and specificity of QUISI to recognize pathological sleep profiles compared with PSG/R&K were 0.92 and 0.96 respectively. QUISI is able to evaluate normal versus altered sleep profiles in patients with primary snoring and OSA. Comparing the quartile ranges, we found substantial differences between QUISI and PSG/R&K. QUISI gives an impression of sleep architecture and objective verification of a sleep disturbance in an ambulant setting but cannot replace the sleep laboratory‐based PSG.     

Quantitative computer‐assisted digital‐imaging upper airway analysis for obstructive sleep apnoea*

This was a prospective study of a new objective method which quantitatively analyses the upper airways in patients with obstructive sleep apnoea (OSA). Video‐nasopharyngoscopic examinations of the upper airways of 45 patients were carried out with an endoscopic calibrator. Images of the upper airway during quiet respiration and Mueller's manoeuvre in erect and supine positions were digitized by computer to generate the actual dimensions of obstructive sites. Measurements by the new method were validated by comparing 90 pairs of videoendoscopic images with upper airway magnetic resonance imaging (MRI) measurements at two identical levels. Quantitative precision is 100% for the retropalatal level and 95.6% for the retrolingual level with a tolerance of 0.5 cm² between the two methods. The absolute mean of the difference between the two methods of measurement is 0.08 cm² at the retropalatal level and 0.18 cm² at the retrolingual level. The agreement between the digital‐imaging videoendoscopic and MRI measurements was 93.3% for the retropalatal level and 95.6% for the retrolingual level. Quantitative computer‐assisted digital imaging is a reliable, cost‐effective clinical method of upper airway evaluation in OSA patients. This method allows us to examine the dynamic and static morphology objectively, measure surgical outcomes of upper airway, opening up new avenues for OSA management.     

Spectacle use and reduced unaided vision in third grade students: a comparative study in different educational settings

Background: The development of myopia is influenced by hereditary factors, environmental factors and geneenvironment interaction. Reading and near‐work activity are associated with myopia and myopic progression. This study sought to determine and compare the prevalence of reduced unaided vision and spectacle use among third grade Israeli students from three different educational settings. Method: A sample of 917 students (mean age 8.5 years, range seven to 10 years) was drawn from the three Israeli educational streams: secular, Orthodox and ultra‐Orthodox. Children in the ultra‐Orthodox education pathway begin studying at the age of three years and their daily reading involves sustained near work with increased accommodative effort accompanied by head‐rocking movements. Reduced distance vision was used to indicate the likely development of or an increase in the amount of myopia. Spectacle lenses were measured to determine the prevalence of myopia. Results: Of the 917 students studied, 103 (11.2 per cent) wore spectacles (14.2 per cent of the males and eight per cent of the females); 82.5 per cent of those who wore spectacles were myopic. Males from ultra‐Orthodox schools had the highest rate of reduced unaided vision (72.5 per cent) compared with males from secular schools (27.3 per cent), males from Orthodox schools (59.3 per cent) or with females from all three groups (average of 34.8 per cent, p < 0.0001, chi squared). Males had a higher rate of reduced unaided vision, especially in the Orthodox and ultra‐Orthodox schools. Conclusions: Our study suggests that Jewish ultra‐Orthodox males have a higher prevalence and degree of myopia. The study habits of young children, including exposure to prolonged near tasks, high accommodative demands and possibly optical defocus induced by body sway, may contribute to the development of myopia.