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1.
Melatonin reduces oxidative stress and improves vascular function in pulmonary hypertensive newborn sheep
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Flavio Torres Alejandro González‐Candia Camilo Montt Germán Ebensperger Magdalena Chubretovic María Serón‐Ferré Roberto V. Reyes Aníbal J. Llanos Emilio A. Herrera 《Journal of pineal research》2015,58(3):362-373
Pulmonary hypertension of the newborn (PHN) constitutes a critical condition with severe cardiovascular and neurological consequences. One of its main causes is hypoxia during gestation, and thus, it is a public health concern in populations living above 2500 m. Although some mechanisms are recognized, the pathophysiological facts that lead to PHN are not fully understood, which explains the lack of an effective treatment. Oxidative stress is one of the proposed mechanisms inducing pulmonary vascular dysfunction and PHN. Therefore, we assessed whether melatonin, a potent antioxidant, improves pulmonary vascular function. Twelve newborn sheep were gestated, born, and raised at 3600 meters. At 3 days old, lambs were catheterized and daily cardiovascular measurements were recorded. Lambs were divided into two groups, one received daily vehicle as control and another received daily melatonin (1 mg/kg/d), for 8 days. At 11 days old, lung tissue and small pulmonary arteries (SPA) were collected. Melatonin decreased pulmonary pressure and resistance for the first 3 days of treatment. Further, melatonin significantly improved the vasodilator function of SPA, enhancing the endothelial‐ and muscular‐dependent pathways. This was associated with an enhanced nitric oxide‐dependent and nitric oxide independent vasodilator components and with increased nitric oxide bioavailability in lung tissue. Further, melatonin reduced the pulmonary oxidative stress markers and increased enzymatic and nonenzymatic antioxidant capacity. Finally, these effects were associated with an increase of lumen diameter and a mild decrease in the wall of the pulmonary arteries. These outcomes support the use of melatonin as an adjuvant in the treatment for PHN. 相似文献
2.
Ferdynand Hebal Elissa Port Catherine J. Hunter Bryan Malas Jared Green Marleta Reynolds 《Journal of pediatric surgery》2019,54(4):656-662
Background/purpose
Computed tomography (CT) derived Haller Index (HI) remains the standard for quantifying severity in patient with pectus excavatum (PE). Optical scanning described in literature reports optimistic results and new indices that correlate with HI. This study assessed the feasibility of a handheld White Light Scanner (WLS) to obtain 3D measurements and indices of PE deformity.Methods
From April 2015–April 2017, WLS scanning was conducted by orthotists during clinical visits. Included were children with PE up to 18?years. Analysis assessed correlation of a WLS-derived severity index, Hebal-Malas Index (HMI), with physician measured PE Depth (PED), and CT-derived HI.Results
Of 195 participants, 185(94%) patients with PE were scanned and 127(69%) had complete WLS data. For 88 patients undergoing monitoring, HMI correlated with PED (r?=?0.42, p?=?0.004). For 39 patients with pre-operative CT, HMI demonstrated strong correlation with HI (r?=?0.87, p < 0.0001).Conclusions
WLS demonstrated high feasibility of scanning PE. WLS-derived HMI best correlates with HI for patients with severe pectus deformity. Our current data is suggestive that WLS is best applied for severe deformities and yet to be established for milder deformities. Future yearly WLS will provide data on deformity progression and surgical therapy.Level of Evidence
IV.Type of Study
Diagnostic Study. 相似文献3.
C. R. Gálvez V. C. Fernández J. M. R. De Los Reyes M. M. M. Jaén & R. G. Teruel 《International journal of gynecological cancer》2004,14(5):1040-1044
Choriocarcinoma is one of the most serious forms of gestational trophoblastic tumor. It is a malignant tumor from the epithelium of the chorionic villi. The most frequent location site is the uterus. Associated with ectopic pregnancy, it is extremely rare and in general, very aggressive. In 75% of the cases, it items from distant metastasis; therefore, a histological examination of the tubes must be performed in all ectopic pregnancies. Our patient was a 33-year-old woman who was admitted to emergency room (ER) with an intense pain in the right, iliac cavity, and limited genital bleeding. During the exploration, there was abdominal pain, with doubtful signs of peritoneal irritation. The vaginal ultrasound offered an image that was compatible with an extra uterine pregnancy in the left appendages. At emergency, right salpingectomy was performed via laparotomy. The patient was treated with polychemotherapy and contraceptives for a year, with no recurrence of the disease. Control follow-up was performed using beta-human chorionic gonadotropin (HCG) testing on a weekly basis during the first month and then bi-monthly during the first year of follow-up. 相似文献
4.
Aneurisma de aorta abdominal infrarrenal en asociación con riñón en herradura: aportación de un caso
Nerea Senarriaga Ruiz de la Illa Reyes Vega Manrique Isabel Lacasa Viscasillas Iñaki Iriarte Soldevilla Miguel Unda Urzaiz 《Actas urologicas espa?olas》2009,33(10):1141-1144
We review the association between surgically resolvable aortic disease and horseshoe kidney with a discussion of diagnostic problems and therapeutic options.Male patient 81 years of age with horseshoe kidney and an abdominal aortic aneurysm that was discovered by chance in an abdominal ultrasound during a check-up for his prostate condition.A retroperitoneal approach was used in order to resect the aneurysm and perform an aorto-aortic bypass with no complications occurring. Two years after the diagnosis, the patient is still asymptomatic from a vascular point of view.The co-presence of horseshoe kidney and aortic disease needing surgical correction is infrequent, but it significantly increases the technical complexity of aortic reconstruction. A literature review is included. 相似文献
5.
Cardiac imaging in the evaluation of patients presenting to the emergency department with chest pain
Conclusions Despite the utility and benefits that each imaging modality has to offer, it is easy to see why there is still no perfect
choice for a noninvasive cardiac imaging modality to assist in the management of chest pain patients. All of the current imaging
techniques have their own significant strengths and weaknesses when compared with other modalities. SPECT and echocardiography
are wellestablished technologies that can directly assess the presence of myocardial ischemia and its functional consequence
on RF; newer and more expensive techniques such as MDCT and CMR can directly assess coronary anatomy and have just started
to be evaluated in the acute chest pain setting. There are no studies that directly compare these technologies, and more data
are clearly needed before the question of whether anatomic imaging versus perfusion/function imaging is the better approach
can be answered. Other comparisons such as relative safety, availability, logistics, and cost-effectiveness between the various
technologies are also lacking.
Of all of the imaging modalities discussed, MCE is the only portable technology. The images do not require expensive software
or other technology for offline processing before interpretation, and any trained cardiologist can read the study at the bedside
or, potentially, over the Internet, providing near-instantaneous results in the acute cardiac setting, where time is of the
essence.
MCE is also relatively cheap compared with other technologies, a potential advantage for payors but not necessarily for payees.
How reimbursement rates and fee structures eventually affect clinical practice is also unknown.
Despite these and other questions that need to be answered before any one technique will be used exclusively, the future of
noninvasive cardiac imaging remains an exciting and ever-changing field. The adaptation of any one of these techniques into
its proper role in the ED Journal of Nuclear Cardiology Wyrick and Wei 753 Volume 13, Number 6;749-55 Cardiac imaging in patients
with chest pain will take considerably more time and effort in terms of research, money, and time-tested clinical experience. 相似文献
6.
Pawan Kumar Dhruva Rao Deborah Clements Michael M. Davies Jared Torkington 《Surgical endoscopy》2007,21(6):1036
We present our comments on the above article. 相似文献
7.
N M Delgado R Reyes A Carranco L Huacuja H Merchant A Rosado 《Archives of andrology》1990,25(2):121-129
The effect of specific glycosaminoglycan-hydrolyzing enzymes on the ruthenium red staining of pig spermatozoa was studied. Washed spermatozoa were incubated at 35 degrees C in buffer or with neuraminidase 0.5 units/ml, heparinase 0.2 mg/ml, or chondroitinase ABC 2.0 units/ml. After incubation sperm cells were washed, stained with ruthenium red and studied under the electron microscope. Anionic sites in the surface of untreated spermatozoa follow regularly the plasma membrane, but present are numerous processes constituting what has been defined as the glycocalyx. Neuraminidase did not affect the distribution of ruthenium red on the surface of the spermatozoa, but eliminated almost completely the processes of the glycocalyx. Heparinase caused loss of the ruthenium red-stained sites on the membrane surface of pig spermatozoa with less influence on the dense processes of the glycocalyx. A similar loss of ruthenium red-stained sites was observed with nitrous acid treatment. A striking effect of treatment with chondroitinase ABC was the production of a typical acrosome reaction. 相似文献
8.
I Madrazo R Franco-Bourland M Aguilera P Reyes G Guízar-Sahagún 《Surgical neurology》1990,33(3):226-227
We have designed a double-lumen inflatable needle for the atraumatic dissection of brain substance. This balloon needle has been successfully used for the ventricular approach in brain grafting procedures to obtain a rounded corticotomy with a diameter of 1.5-2 cm in the treatment of Parkinson's disease. 相似文献
9.
10.
Radiotherapy has been successful in treating localized prostate cancer; however, a subset of patients will experience disease
recurrence. Determination of the recurrence location must be made using pretreatment and posttreatment clinical variables,
imaging, and postradiotherapy biopsy. Patients presumed to have local-only recurrence, optimal clinical risk factors, and
an extended life expectancy may be considered for salvage local treatment. Current options include salvage surgery, cryoablation,
and brachytherapy. Although they are associated with higher morbidity than primary therapy, salvage treatments can be effective
and can still provide patients with a good oncologic and functional outcome. As these modalities continue to improve and patient
selection is optimized, better results will evolve. 相似文献