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991.
Headache induced by a nitric oxide donor (nitroglycerin) responds to sumatriptan. A human model for development of migraine drugs 总被引:5,自引:0,他引:5
Experimental "vascular" headache in humans may be used in characterizing new migraine drugs. The effects of sumatriptan on nitroglycerin-(NTG)-induced headache and arterial responses were therefore studied. Following a double-blind randomized crossover design, 10 healthy volunteers received sumatriptan 6 mg s.c. or placebo succeeded by 20 min NTG (0.12 mg/kg/min) infusion. Headache was rated on a 10 points scale. Temporal and radial artery diameters and velocity in the middle cerebral artery (MCA) were measured with ultrasound. Sumatriptan reduced the NTG-induced headache, median score 1.5 versus 4 after placebo ( p <0.01) and decreased temporal and radial artery diameters 75±3 and 86±3% of baseline respectively ( p <0.05), Blood velocity in the MCA was unaffected. The NTG model may prove to be a valuable tool in the development of future migraine drugs. The results suggest that NTG headache in non-migraineurs may share mechanisms with migraine headache. 相似文献
992.
993.
Paul R. Burton Wendy Brown Cheryl Laurie Melissa Richards Sohail Afkari Kenneth Yap Anna Korin Geoff Hebbard Paul E. O’Brien 《Obesity surgery》2009,19(7):905-914
Background Laparoscopic adjustable gastric bands (LAGB) are a safe and effective treatment for obesity. Conflicting data exist concerning
their effect on the esophagus, gastroesophageal junction, and mechanism of action. These patients will increasingly require
accurate assessment of their esophageal function.
Methods Twenty LAGB patients underwent high-resolution video manometry with the LAGB empty, 20% under, 20% over, and at their optimal
volume. Twenty obese controls were also studied. Effects on esophageal motility, the lower esophageal sphincter (LES), and
the gastroesophageal junction were measured. Transit during liquid and semisolid swallows was assessed.
Results The intraluminal pressure at the level of LAGB was a mean of 26.9 (19.8) mm Hg. This pressure varied depending on the volume
within the LAGB and was separate to and distal to the lower esophageal sphincter LES. The LES was attenuated compared to controls
(10 vs 18 mm Hg; p < 0.01) although relaxed normally. Esophageal motility was well preserved at optimal volume compared to 20% overfilled, with
77% normal swallows vs 51%, p = 0.008. Repetitive esophageal contractions were observed in 40% of swallows at optimal volume compared to 16% in controls,
p = 0.024. In comparison to controls, the transit of liquid, 21 vs 8 s (p < 0.001), and semisolids, 50 vs 16 s (p < 0.001), was delayed.
Conclusions In LAGB patients, the LES is attenuated, although relaxes normally. Esophageal motility is preserved, although disrupted by
overfilling the band. In the optimally adjusted LAGB, a delay in transit of liquids and semisolids through the esophagus and
band is produced, along with an increase in repeated esophageal contractions.
Paul Burton has received funding from the National Health and Medical Research Council (NHMRC) and the Royal Australasian
College of Surgeons. 相似文献
994.
Nicholas A. Faure Walker Joseph M. Norris Taimur T. Shah Tet Yap Paul Cathcart Caroline M. Moore Hashim U. Ahmed Mark Emberton Suks Minhas 《Urologic oncology》2018,36(2):67-76
Objectives
To systematically review erectile function (EF) outcomes following primary whole gland (WG) and focal ablative therapies for localized prostate cancer to ascertain whether the treatment modality or intended treatment volume affects the time taken to recover baseline EF.Method and materials
A systematic review was performed according to the preferred reporting items for systematic review and meta-analysis statement. Inclusion criteria were men with localized prostate cancer treated with primary, ablative therapy. Primary outcome was the return to baseline EF measured with objective, validated symptoms scores. Secondary outcome was use of phosphodiesterase inhibitors or erectile aids. Meta-analysis was not performed owing to heterogenous outcome measures.Results
Of 222 articles identified in February 2017, 55 studies which reported EF after ablative therapy were identified but only 17 used validated outcome measures and met inclusion criteria. WG cryotherapy was used in 2 studies, WG high-intensity focused ultrasound (HIFU) in 5, focal cryotherapy in 2, focal HIFU in 3, focal phototherapy or laser therapy in 4, vascular-targeted photodynamic therapy in 3, and irreversible electroporation in 2. WG cryotherapy was associated with a significant decline in EF at 6 months with minimal improvement at 36 months. Baseline IIEF-15 of patients undergoing focal HIFU fell 30 points at 1 month but returned to baseline by 6 months. The remaining focal therapies demonstrated minimal or no effect on EF, but the men in these studies had small foci of disease. The review is limited by lack of randomized studies and heterogenous outcome measures.Conclusions
Most studies assessing the outcomes of focal therapy on sexual function were not of high quality, used heterogenous outcomes, and had relatively short follow up, highlighting the need for more robustly designed studies using validated patient reported outcome measures for comparison. However, FT in general resulted in less effect on EF than WG ablation. 相似文献995.
An abnormal, convex systolic anterior motion of the mitral valve, somewhat similar to that seen in idiopathic hypertrophic subaortic stenosis (hypertrophic obstructive cardiomyopathy) and occasionally in atrial septal defect, was found on the echocardiogram in 8 out of 9 patients with angiographically (7 patients) and/or clinically (2 patients) diagnosed left ventricular aneurysm secondary to myocardial infarction. The only patient whose echocardiogram failed to demonstrate convex systolic anterior motion was the only patient who had an inferior wall aneurysm; the rest of the group had anterior and/or apical aneurysms. In contrast to patients with typical idiopathic hypertrophic subaortic stenosis, the convex systolic anterior motion of the mitral valve observed in our patients tended to 'peak' rather than 'plateau'. Through the basis for this abnormal septal motion in our patients is uncertain, alterations in left vantricular configuration, plus a relatively vigorously contracting posterior left ventricular wall in the presence of abnormal interventricular septal motion, are probable contributory factors. Though non specific, in the proper clinical and echocardiographic setting convex systolic anterior motion of the mitral valve may be another sign of left ventricular aneurysm. 相似文献
996.
CY Silva KL Brown AK Kurban M Mahalingam 《Indian journal of dermatology, venereology and leprology》2012,78(5):611-619
Background: The incidence of psoriatic alopecia in psoriatic patients is underwhelming, given the prevalence of psoriasis in the North American population. Recently, a 60-year-old Albanian female, lacking a significant medical history for psoriasis, presented to our clinic with a 1-year history of "dandruff" associated with itch, hair thinning, and histopathologic evidence consistent with prior reports of "psoriatic alopecia." Aims: The absence of preceding or concomitant psoriasis suggests that the patient's alopecia is an antecedent manifestation of psoriasis, thus prompting this retrospective study to ascertain better the relationship between alopecia and psoriasis. Methods: We performed a retrospective review of 33 scalp biopsies on 31 patients having histopathologic diagnosis of psoriasis belonging to 31 patients seen between 2007 and 2010. Results: Alopecia was a presenting feature in 48% of cases with definitive clinical and/or histopathologic diagnosis of psoriasis (scale crust with neutrophils, psoriasiform epidermal hyperplasia, and hypogranulosis). The most common follicular-related changes were infundibular dilatation (87%) followed by perifollicular fibrosis (77%), perifollicular lymphocytic inflammation (68%), thinning of the follicular infundibulum (55%), and fibrous tracts (28%). Of interest, sebaceous glands were absent in 60% and atrophic in 25% of cases. Conclusion: While a major limitation of this study is that it is a retrospective one, given that these changes are common to varying degrees in all lymphocytic scarring alopecias, we posit that psoriatic alopecia likely represents a secondary clinical change to a primary process and is not a unique histopathologic entity. A prospective study with a control group that includes lymphocytic scarring alopecias from non-psoriatic patients is required to support our findings. 相似文献
997.
Shier Nee Saw Jess Yi Ru Low May Han Huang Ong Yu Wei Poh Citra Nurfarah Zaini Mattar Arijit Biswas Choon Hwai Yap 《Annals of biomedical engineering》2018,46(7):1066-1077
Intrauterine Growth Restriction (IUGR) is a serious and prevalent pregnancy complication that is due to placental insufficiency and IUGR babies suffer significantly higher risks of mortality and morbidity. Current detection rate for IUGR is generally poor and thus an alternative diagnostic tool is needed to improve the IUGR detection. Elastography, a non-invasive method that measures the tissue stiffness, has been proposed as one such technique. However, to date, we have limited information on the mechanical properties of IUGR placenta. In this study, we investigated the mechanical properties of normal and IUGR placentae and prescribed a suitable hyperelastic model to describe their mechanical behaviors. A total of 46 normal and 43 IUGR placenta samples were investigated. Results showed that placenta samples were isotropic, but had a high spatial variability of stiffness. The samples also had significant viscoelasticity. IUGR placenta was observed to be slightly stiffer than normal placenta but the difference was significant only at compression rate of 0.25 Hz and with 20% compression depth. Three simple hyperelastic models—Yeoh, Ogden and Fung models, were found to be able to fit the experimentally measured mechanical behaviors, and Fung model performed slightly better. These results may be useful for optimizing placenta elastography for the detection of IUGR. 相似文献
998.
The cognitive–behavioural model of hoarding disorder: Evidence from clinical and non‐clinical cohorts 下载免费PDF全文
Michael Kyrios Christopher Mogan Richard Moulding Randy O. Frost Keong Yap Daniel B. Fassnacht 《Clinical psychology & psychotherapy》2018,25(2):311-321
The cognitive–behavioural model of hoarding disorder incorporates information processing difficulties, maladaptive attachment to possessions, erroneous beliefs about the nature of possessions, and mood problems as etiologically significant factors, although developmental experiences such as a compromised early family environment have also been proposed in an augmented model. This study examined the specificity and relevance of variables highlighted in the augmented cognitive–behavioural model. Various clinical participants (n = 89) and community controls (n = 20) were assessed with structured clinical interviews to verify diagnosis. Participants completed self‐report measures of hoarding severity, cognitions, meta‐memory, and early developmental experiences (e.g., memories of warmth and security in one's family). Hoarding cohorts (with and without obsessive–compulsive disorder) reported poor confidence in memory, but relative to other groups (obsessive–compulsive disorder without hoarding disorder, anxiety disorders, and healthy controls), hoarding‐relevant cognitions, need to keep possessions in view, and concerns about the consequences of forgetting were significantly higher. Hoarding groups reported the lowest recollections of warmth in their family, although no differences were found between hoarding and non hoarding clinical cohorts for uncertainty about self and others. Nonetheless, clinical cohorts reported generally higher scores of uncertainty than healthy controls. When predicting hoarding severity, after controlling for age and mood, recollections of lack of warmth in one's family was a significant predictor of hoarding severity, with hoarding‐related cognitions and fears about decision‐making being additional unique predictors. The study supports the augmented cognitive–behavioural model of hoarding, inclusive of the importance of early developmental influences in hoarding. 相似文献
999.
Hadi Wiputra Guat Ling Lim Khong Chun Chua R. Nivetha Sanah Merchant Soomar Arijit Biwas Citra Nurfarah Zaini Mattar Hwa Liang Leo Choon Hwai Yap 《Annals of biomedical engineering》2017,45(10):2335-2347
In both adult human and canine, the cardiac right ventricle (RV) is known to exhibit a peristaltic-like motion, where RV sinus (inflow region) contracts first and the infundibulum (outflow region) later, in a wave-like contraction motion. The delay in contraction between the sinus and infundibulum averaged at 15% of the cardiac cycle and was estimated to produce an intra-ventricular pressure difference of 15 mmHg. However, whether such a contractile motion occurs in human fetuses as well, its effects on hemodynamics remains unknown, and are the subject of the current study. Hemodynamic studies of fetal hearts are important as previous works showed that healthy cardiac development is sensitive to fluid mechanical forces. We performed 4D clinical ultrasound imaging on eight 20-weeks old human fetuses. In five fetal RVs, peristaltic-like contractile motion from the sinus to infundibulum (“forward peristaltic-like motion”) was observed, but in one RV, peristaltic-like motion was observed from the infundibulum to sinus (“reversed peristaltic-like motion”), and two RVs contraction delay could not be determined due to poor regression fit. Next, we performed dynamic-mesh computational fluid dynamics simulations with varying extents of peristaltic-like motions for three of the eight RVs. Results showed that the peristaltic-like motion did not affect flow patterns significantly, but had significant influence on energy dynamics: increasing extent of forward peristaltic-like motion reduced the energy required for movement of fluid out of the heart during systolic ejection, while increasing extent of reversed peristaltic-like motion increased the required energy. It is currently unclear whether the peristaltic-like motion is an adaptation to reduce physiological energy expenditure, or merely an artefact of the cardiac developmental process. 相似文献
1000.