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21.
Matrix metalloproteinases (MMPs) and cysteine cathepsins (CCs) can break down unprotected type I collagen fibrils in dentin matrix. This study investigated the use of potassium fluoride (KF) as a potential inhibitor of MMPs and CCs in dentin. Demineralized dentin beams were divided into groups (n = 10 in each group) and incubated in artificial saliva (AS, control), either alone or with one of seven concentrations of KF (6–238 mM fluoride) for 1, 7, and 21 d. After 21 d, all groups were further aged in AS for 6 months. Total MMP activity was screened using the colorimetric MMP assay. The activities of MMP‐2 and MMP‐9 were investigated using gelatin zymography. At the end of each incubation, changes in loss of dry mass and CC‐mediated or total dissolution of collagen peptides were measured via precision weighing, C‐terminal crosslinked telopeptide of type I collagen (CTX), and hydroxyproline (HYP) assays. The beams were examined using scanning electron microscopy. After 21 d, total MMP activities, dry mass loss, and CTX release for the groups exposed to 179 and 238 mM fluoride were significantly lower compared with the control group. After 6 months, all groups showed similar total MMP activity, dry mass loss, and HYP release, and CTX levels were significantly lower when the fluoride concentration was ≥24 mM. Calcium fluoride (CaF2)‐like precipitates were observed over the beams. In summary, KF significantly inhibited the catalytic activity of dentin matrix‐bound CCs but did not seem to be effective for MMP‐mediated activity.  相似文献   
22.
The following study was conducted to adapt the Auditory Consonant Trigram Test (ACT) to Turkish, acquire a new and larger set of normative data, and finally investigate the reliability and validity of the adapted version. The data were collected from a sample of 236 healthy individuals. To test the validity of the Turkish version of ACT, the normative results of ACT were first compared with those obtained from the Digit Span Test (DST) backwards section. Secondly, the ACT performance of 53 schizophrenic patients was compared with that of a matched group selected from the normative sample. Age and education variables influenced performance, whereas gender did not in the normal sample. The ACT and DST backwards scores were positively correlated. As expected, the ACT performance was worse in schizophrenic patients compared to controls. The internal consistency of the adapted version of ACT was found to be at a reliable level (a=0.8535). The Turkish version of ACT can be considered to be a reliable and valid measure of working memory.  相似文献   
23.
We studied the effects of treatment with SMe1EC, a hexahydropyridoindole antioxidant, on vascular reactivity, endothelial function, and oxidonitrosative stress level of thoracic aorta in young and old rats with or without diabetes mellitus. The rats were grouped as young control (YC 3 months old), old control (OC 15 months old), young diabetic (YD), old diabetic (OD), young control treated (YCT), old control treated (OCT), young diabetic treated (YDT), and old diabetic treated (ODT). Diabetes was induced by streptozotocin injection and subsequently SMe1EC2 (10 mg/kg/day, p.o.) was administered to YCT, OCT, YDT, and ODT rats for 5 months. In young and old rats, diabetes resulted in hypertension, weight loss, hyperglycemia, and hypertriglyceridemia, which were partially prevented by SMe1EC2. SMe1EC2 also inhibited the diabetes-induced increase in aorta levels of AGEs (advanced glycosylation end-protein adducts), 4-HNE (4-hydroxy-nonenal-histidine), 3-NT (3-nitrotyrosine), and RAGEs (receptors for AGEs). The contractions of the aorta rings to phenylephrine (Phe) and KCL did not significantly change, but acetylcholine (ACh) and salbutamol relaxations were reduced in OC compared to YC rats. Diabetes induction increased Phe contractions in YC and OC rats, KCL contractions in YC rats, and did not cause further inhibition in already inhibited ACh and salbutamol relaxations in OC rats. We have achieved the lowest levels of ACh relaxation in YD rats compared to other groups. SMe1EC2 did not change the response of aorta to ACh, salbutamol and Phe in YC rats, and ameliorated ACh relaxations in OC and YD but not in OD rats. In YDT and ODT rats, increased Phe and KCL contractions, high blood pressure, and impaired salbutamol relaxations were amended by SMe1EC2. Phe contractions observed in YD and OD rats as well as KCl contractions observed in OC rats were the lowest levels when the rats were treated with SMe1EC2. When the bath solution was shifted to cyclopiazonic acid (CYP) or CYP plus Ca2+-free medium, the contraction induced by a single dose of Phe (3?×?10?6 M) was more inhibited in YD and OD than in YC but not in OC rats. In SMe1EC2-treated rats, neither the presence of CFM nor CFM plus CYP exhibited a significant change in response of aorta to a single dose of Phe. These findings suggest that α1-adrenergic receptor signaling is activated in both age groups of diabetic rats, diabetes activates K+-depolarization and calcium mobilization via CaV especially in the aorta of young rats, and sensitizes the aorta of old rats to the regulating effect of SMe1EC2. ACh relaxations were inhibited in YC rats, increased in OC rats and unchanged in YD and OD rats when aortic rings pretreated with TEA, an inhibitor of calcium-activated K+ channels (KCa), or 4-aminopyridine (4-AP), an inhibitor of voltage-sensitive K+ channels (KV). ACh relaxations were inhibited in YCT, OCT, and YDT rats in the presence of 4-AP or TEA. In ODT rats, 4-AP did not change ACh relaxation but TEA inhibited. These findings suggest that the contribution of Kv and KCa to ACh relaxation is likely upregulated by SMe1EC2 when the relaxations were inhibited by aging or diabetes. We conclude that SMe1EC2 might be a promising agent for aging and diabetes related vascular disorders.  相似文献   
24.
Torsion of the fallopian tube accompanying hydrosalpinx is a rare occurrence in the pediatric population. This report describes a 13 year old sexually inactive girl with isolated tubal torsion due to hydrosalpinx. The girl had lower left abdominal pain for two days. The physical examination revealed left lower quadrant tenderness with a firm round anterior mass on rectal examination. Abdominal ultrasound showed left tubal enlargement with free pelvic peritoneal fluid. Magnetic Resonance Imaging (MRI) showed engorgement and dilatation of the left fallopian tube without contrast enhancement suspicious of tubal torsion. At operation, torsion of the left tube on its longitudinal axis was observed, and a salpingectomy was performed.  相似文献   
25.
Development of secondary amyloidosis is an infrequent complication in patients with Behçet's syndrome (BS). It has been reported that multiple systemic involvement, long disease duration, and male gender are major clinical factors accompanying the development of amyloidosis in BS. We report a case of secondary amyloidosis in a patient diagnosed as having BS with a positive pathergy test 9 years previously and who had isolated mucocutaneous involvement. Regular use of colchicine since the diagnosis and somewhat mild progress of the disease could not prevent the development of secondary amyloidosis in this patient. He is alive and receives hemodialysis regularly.  相似文献   
26.
Three clusters of Chryseobacterium meningosepticum infections in a tertiary health center in July 2006 and January 2007 involving 8 newborns and 5 older children were investigated. The index patient was from the neonatal intensive care unit, and the older patients were from other pediatric wards. Cultures were obtained from the environment and from health care workers' hands as part of an outbreak investigation. C meningosepticum was isolated from hand cultures obtained from a senior resident and from environmental cultures obtained from powdered infant formula, an electrical button, a computer keyboard, phone, a doorknob, and an Ambu bag. Antibiogram typing and enterobacterial repetitive intergenic consensus sequence polymerase chain reaction indicated that all of the isolates were epidemiologically related. Nine patients improved on antimicrobial treatment, and 4 premature infants died after the infection. C meningosepticum is a well-known etiologic agent for nosocomial infections involving newborns and immunocompromised patients. Wet and dry environmental surfaces and equipment may act as a source or play a role in disseminating the microorganism. Outbreaks may be controlled with strong emphasis on infection control measures.  相似文献   
27.
Objective: The aim of present study was to evaluate the indications and the complications associated with neonatal exchange transfusion (ET) performed for hyperbilirubinemia.

Methods: This study included overall 306 neonates who underwent ET between 2005 and 2012. The demographic characteristics of patients, causes of jaundice and adverse events occurred during or within 1 week after ET were recorded from their medical files. Those newborns that underwent ET were classified as either “otherwise healthy” or “sick” group.

Results: Of the 306 patients who underwent ET, 244 were otherwise healthy and had no medical problems other than jaundice. The remaining 62 patients were classified as sick that had medical problems other than jaundice ranging from mild to severe. The mean gestational age was 37.6?±?2.5 weeks and the mean peak total bilirubin levels was 25.8?±?6.6?mg/dl. The mean age at presentation was 5.4?±?3.8?d for all infants. The most common cause of hyperbilirubinemia was ABO isoimmunization (27.8%). None of newborns died secondary to ET. Three infants had had necrotizing enterocolitis, and also three infants had had acute renal failure. The most common encountered complications of ET procedure were hyperglycemia (56.5%), hypocalcaemia (22.5%) and thrombocytopenia (16%).

Conclusions: Our data showed that ABO isoimmunization was the most common cause of hyperbilirubinemia. Even mortality was not seen, very rare but major gastrointestinal and renal complications were associated with ET. The majority of adverse events associated with ET were laboratory abnormalities mainly hyperglycemia, hypocalcaemia and thrombocytopenia which were asymptomatic and treatable.  相似文献   
28.

Objectives

Confirmation of the endotracheal tube placement (CoETP) has the utmost importance in the management of an airway. Visualization of tracheal rings or carina with a fiber-optical bronchoscope (FOB) has considered to be a reliable method for the CoETP. However, FOB is expensive, time-consuming, and not always practical. Inexpensive endoscopic USB-cameras were shown to aid intubation successfully and reliably. On the other hand, there have been no studies investigating their use for the CoETP. Tracheal ultrasonography (TUS) is also a new, inexpensive and widely available alternative. A cadaver study has planned to evaluate the diagnostic utility of TUS and a USB-camera.

Methods

This study was conducted in the Anatomy Lab of a University on a fresh frozen female cadaver. Three senior Emergency Physicians have intubated the cadaver, and performed TUS or USB-endoscopy. We have prepared a randomized intubation list (n = 96) in three blocks (3 times 32) as to include equal number of esophageal and tracheal intubations (48 for each). Each EP is performed all three interventions (intubation, TUS and USB-endoscopy) in consecutive blocks of 32 intubations, in turn. The position of the tube has been verified from a 2 cm wide ostium on the proximal trachea.

Results

In this study, all intubations (n = 96, 100%) were correctly identified as tracheal or esophageal with both TUS and USB-camera. Both the sensitivity and specificity of TUS and USB-endoscopy for the CoETP were 100.0%.

Conclusion

The perfect accuracy of TUS and USB-endoscopy, have placed those techniques in a unique position as an alternative in resource-poor situations.  相似文献   
29.

Introduction

The diagnostic accuracy of the FAST exam performed by EM residents were shown to be similar to radiology residents. However, in the last 2 decades, an extended-FAST (E-FAST) protocol including thoracic examination to exclude pneumo- and hemothorax was introduced. The accuracy of emergency physicians (EPs) while performing E-FAST is a less studied area, especially in Europe. The aim of this study was to compare the diagnostic accuracy of the E-FAST exam performed by EM residents with the results of CT scan as a gold standard.

Methods

This was a prospective, observational, diagnostic accuracy study conducted at the ED of a Level 1 Trauma Center. All consecutive adult multiple trauma patients were eligible, and any patient in whom thoraco-abdominal CT was ordered were recruited. Unstable and unavailable patients were excluded. E-FAST examination was performed by EPs as the index test, and CT examinations reported by a blinded academic radiology faculty was the gold standard.

Results

A total of 140 patients were recruited from eligible 144 patients. The final study population was 132 for abdominal and 130 for thorax examinations. In this study, AUC of E-FAST was 0.71 for abdominal free fluid, 0.87 for pneumothorax and 1.00 for pleural effusion. The sensitivity was 42.9% and specificity was 98.4%. The + LR for abdominal free fluid was 26.8 and ? LR was 0.58.

Conclusion

E-FAST examination has an excellent specificity. However, the sensitivity of the test is not high enough to rule-out thoraco-abdominal injuries in trauma patients when performed by EPs.  相似文献   
30.

Purpose

To evaluate the efficiency of perforated punctal plug in acquired punctal stenosis.

Materials and methods

Forty-five eyes of 33 patients who had epiphora due to punctal stenosis were included in this study. After biomicroscopic examination and lacrimal dilatation punctal stenosis was managed with the perforated punctal plugs in all patients. In the following period epiphora, plug tolerance, lacrimal drainage were evaluated and graded. Lacrimal drainage was evaluated with fluorescein dye disappearing test.

Results

The age of the patients ranged between 31 and 80 (mean 55.78 ± 13.11). Preoperatively punctal dilatation and lacrimal system irrigations were performed on all patients. Lacrimal system irrigation was positive in all patients. Perforated punctal plugs were placed in the inferior puncti in all patients. The plugs were explanted 6 months after operation. The follow-up period ranged between 6 and 24 months. Plug tolerance was good in 97.8% of the eyes in the 1st month visit. Epiphora decreased remarkably in 88.9% of the patients 1 month after plug implantation, except one whose plug dropped off spontaneously in 2 weeks. Fluorescein disappearing times were found under 3 min in 97.8% of the eyes after plug explanations.

Conclusion

Punctum stenosis is one of the several disorders that cause lacrimal drainage obstruction. Perforated punctal plugs are found convenient and effective in managing punctal stenosis.  相似文献   
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