Is heat shock protein a potential protective mechanism against ischemia-reperfusion injury?
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Animals↗
Biomedical subjects
C Y Su
Publications and source records attributed to C Y Su.
Intraocular use of fluconazole in the management of ocular fungal infection.
In this study, we investigate the efficacy and safety of intraocular use of fluconazole in the treatment of ocular fungal infection. Ten patients with intraocular fungal infections were examined. Among these patients, eight were infected with keratomycosis with intraocular spreading, one had postoperative fungal endophthalmitis after cataract operation with an intraocular lens implant, and another suffered from endogenous fungal endophthalmitis. In addition to the conventional local application with or without systemic administration of antifungal drugs, all ten patients were treated with intraocular administration of 5-10 micrograms/ml of fluconazole. The ocular fungal infections resolved in nine patients without obvious side effect. One failed in the antifungal treatment with loss of vision. In our experience, the results revealed that fluconazole is a safe and effective antifungal agent that can be administered intraocularly. We suggest that intraocular administration of this drug could be considered as an alternative or additional choice for the treatment of severe ocular fungal infections.
Adult↗
Constitutive and inducible hsp70s are involved in oxidative resistance evoked by heat shock or ethanol.
Improved cardiac post-ischemic recovery after whole-body hyperthermia is correlated with an increased expression of the heat shock proteins (hsps). The inducible hsp70 (hsp70i) has a known cardioprotective effect against ischemia/reperfusion injury. Here, we studied whether other hsps are also involved in cardioprotection. Using rat heart-derived H9c2 myocytes, we observed that preheating at 43 degreesC for 20 min conferred resistance to hydrogen peroxide (H2O2). The resistance to mild H2O2 toxicity (3-5 micro mol/10(7) cells) appeared early and persisted, whereas the resistance to moderate H2O2 toxicity (6-9 micro mol/10(7) cells) was detectable only at 20-44 h post heat shock. No resistance was observed at higher doses of hydrogen peroxide (10-12 micro mol/10(7) cells), indicating that severe toxicity exceeds the capacity of the induced protective mechanism. Coincidentally, this thermal regimen elicited a rapid and prolonged increase in the cellular level of hsp70i, and a delayed and transient induction of the constitutive hsp70 (hsp70c). Nuclear translocations of hsp70i and hsp70c also occurred upon heat stimulation. A homogeneous distribution of the accumulated hsp70i and hsp70c throughout the nuclei and cytoplasm paralleled the development of heat-induced resistance to moderate H2O2 challenge. Application of another hsp inducer, ethyl alcohol, evoked a similar pattern of H2O2 resistance, and hsp induction and distribution. Our results suggest that induction and subcellular distribution of hsp70s contribute importantly to cellular antioxidant defenses, and that a co-operation between hsp70i and hsp70c may improve cardiac preservation during oxidative insult.
Animals↗
Stable overexpression of the constitutive form of heat shock protein 70 confers oxidative protection.
We have previously reported that thermal preconditioning confers an oxidative resistance in rat heart-derived H9c2 myocytes. The development of this resistance is associated with a co-expression of both inducible (hsp70i) and constitutive (hsp70c) forms of the 70-kD heat shock proteins, suggesting an antioxidant role for these proteins. Overexpression of hsp70i has been shown to render cells more tolerant to oxidative challenge. The present study sought to determine whether increases in hsp70c, the constitutive member of this protein family, are also positively correlated to oxidative protection. A rat cDNA encoding hsp70c was inserted into a mammalian expression vector, allowing transcription of the inserted gene to be regulated by a powerful cytomegaloviral promoter. After introduction of this construct into H9c2 myocytes, stable clones were obtained. Western and Northern blot analysis of the derived clones showed a two-fold increase in hsp70c mRNA and protein concentrations. These clones were more resistant to thermal killing when compared to control cells transfected with the vector alone, implicating a functional role for the overexpressed hsp70c protein. hsp70c-enriched cells also exhibited a marked resistance to oxidative challenges, including exposure to hydrogen peroxide (H2O2), hydroxyl radical, menadione, and hypoxia/reoxygenation. These findings indicate that hsp70c overexpression provides a protective effect against endogenous or exogenously generated reactive oxygen species (ROS), suggesting that hsp70c actively participates in the heat shock-induced oxidative protection.
Animals↗
Internal carotid artery aneurysm presenting as an unusual nasopharyngeal mass.
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Adult↗
Revision surgery of a stenotic speaking shunt in near-total laryngectomy patients.
A near-total operation to create a speaking shunt is generally considered a suitable option in most T3 laryngopharyngeal cancer cases. However, some of these cases incur postoperative problems, including aspiration and shunt stenosis. In this 8-year study, 15 of 60 patients who had received near-total laryngectomies could not speak well with their shunts. Revision surgery was performed on 11. Under local anesthesia, the lumen of the stenotic segment of the shunt was opened. A 4-F silicone tube was stented in the shunt. Then, for mildly stenotic cases, the small mucosal defect of the shunt was covered by a sternohyoid myofascial flap. For moderate to severe cases, the larger mucosal defect was reconstructed with a free skin graft. Thereafter, a sternohyoid muscle flap was used to cover the skin graft, which would finally form the inner lining of the new speaking shunt. The outcome was that 9 of the 11 patients acquired intelligible shunt speech. These results demonstrate that the augmentation procedures described herein have considerable potential for restoring the function of a stenotic speaking shunt in a near-total laryngectomy.
Aged↗
Keratomycosis with an unusual clinical manifestation--a case report.
We report a case of keratomycosis which had recurrent, deep stromal infiltration and an endothelial plaque for half a year after the original corneal foreign body injury. The subject had an unusual clinical picture of deep corneal infiltration and later hair-like material growing from the endothelial plaque into the anterior chamber. Repeated corneal scrapings for smears and cultures all showed negative during the initial treatment. We tried anterior chamber paracentesis and endothelial aspiration and got a positive finding of Cladosporium infection. This case is presented because of the difficulty of diagnosis and management of fungal keratomycosis.
Cladosporium↗
Stereomorphologic observation of bone tissue response to hydroxyapatite using SEM with the EDTA-KOH method.
To obtain further information on the interaction of hydroxyapatite (HA) and the bony implantation bed, 20- to 40- mesh dense HA particles were implanted into the tibiae of dogs. Following healing periods of 2 weeks, 1 month, and 3 months, the specimens were retrieved and prepared by either conventional preparatory procedures for scanning electron microscopy (SEM) of the EDTA-KOH method. Under SEM observation, the interparticular osteogenesis among HA particles progressed in a programmed sequence. Ample blood supply and osteoblasts initially presented in the interparticular space. The secretion of bone matrix resulted in the formation of immature bone. This scaffold was then transformed into mature lamellar bone during the following bone remodeling process. The serial changes closely resembled the pattern viewed in controls that did not implant HA. A spatial relationship between bone cells and HA was clearly demonstrated. In particular, the osteoblasts displayed an extremely flat appearance with many microappendages. The microappendages anchored cells to the HA surface and fused with granular material covering the HA crystals. The more characteristic cellular morphology was revealed by the EDTA-KOH method. Microscopic pictures clearly identified the three-dimensional images of ruffled borders of osteoclasts and the slender cytoplasmic processes of osteocytes. This study provided further evidence for the favorable biological response of HA to bone cells as well as the value of the EDTA-KOH method in examining the stereomorphology of bone cells.
Animals↗
Aspiration and speech shunt stenosis in near-total laryngectomy patients.
A near-total laryngectomy or near-total laryngopharyngectomy with the creation of a speech shunt was carried out on 66 laryngopharyngeal cancer patients. Intelligible shunt speech was obtained in 50 patients (76%), while stenosis of the shunt occurred in 13 patients (20%), and asymptomatic aspiration in 4 (6%). Poor voice production was usually due to shunt stenosis, a fibrotic band surrounding the shunt, or local recurrence of tumor. Perioperative wound infection and postoperative irradiation did not interfere with the development of shunt speech. In 12 patients with shunt stenosis, revision surgeries were performed to augment the shunt openings. During these procedures, the stenotic shunt was opened and a silastic tube was introduced into the shunt lumen to serve as a stent. For the moderately to severely stenotic shunt, the mucosal defect present was covered with a free skin graft or a sternocleidomastoid myoperiosteal flap. Following treatment, results demonstrated that 10 of the 12 patients acquired satisfactory shunt speech. In two unsuccessful cases, the causes of failure were wound infection and graft necrosis and were presumed to be complications of previous irradiation.
Adult↗
The relapse patterns and outcome of postoperative recurrent tongue cancer.
PURPOSE: The relapse patterns and salvage treatment results for patients who developed locoregional recurrence after surgery for squamous cell carcinoma of the tongue were retrospectively analyzed. MATERIALS AND METHODS: Between April 1986 and January 1995, 77 cases with recurrent squamous cell carcinoma of the tongue were evaluated. Most of them were males in the early stages of initial disease. Although the surgical margins were negative in most cases (67 of 77), relapse eventually occurred. The relapse patterns showed 15 patients with primary recurrence, 45 patients with regional neck lymph node (LN) relapse, and 17 patients with relapse in both sites. RESULTS: Salvage treatment was given to most of the patients, but their median survival time was only 9 months. Survival data were analyzed and compared with different types of relapse patterns, salvage treatments, disease-free intervals, age, and sex. In univariate analysis, the neck LN relapse and shorter relapse-free interval (< 6 months) were poor prognostic factors (P < .05), and surgical treatment showed a trend for better salvage results (P = .0575). In multivariate analysis, patients with neck LN relapse had the worst outcome (P < .05). CONCLUSIONS: Recurrence of tongue cancer is not uncommon, but there are little data in literature regarding the prognosis. Although this study showed poor salvage results, various prognoses could be predicted on the bases of the different relapse patterns and salvage methods.
Adult↗
Perineural invasion of the trigeminal nerve in patients with nasopharyngeal carcinoma. Imaging and clinical correlations.
BACKGROUND: A nasopharyngeal carcinoma (NPC) arising from the fossa of Rosenmüller frequently extends to the paranasopharyngeal space. The common clinical manifestations are neck masses, ear symptoms, bloody nasal discharge, and cranial nerve palsy. Among the patients with cranial nerve palsy, trigeminal neuropathy is one of the most observable neurologic manifestations. This study was designed to evaluate trigeminal perineural tumor invasion. METHODS: One hundred and ten patients with newly diagnosed NPC were studied. Both computed tomography and magnetic resonance imaging of the head and neck, including the nasopharynx, were performed during the same visit. The extent of the trigeminal perineural tumor invasion was evaluated and correlated with neurologic symptoms. RESULTS: At the time of diagnosis, facial pain or paresthesia was noted in 23.6% (26 of 110) of the patients. However, 53.6% (59 of 110) of the patients radiologically had demonstrable trigeminal perineural tumor invasion. Perineural invasion of the extracranial portion of the mandibular division (V3) frequently occurred when an NPC encroached on the paranasopharyngeal region. Nevertheless, the patients usually did not have any subjective sensory impairment. Perineural invasion of the intracranial segment of the mandibular and maxillary divisions (V2) might occur when an NPC spread along the V3 through the foramen ovale. The majority of the patients who had tumor invasion of the intracranial paracavernous region suffered from facial pain or paresthesia over the distribution of the V2 and/or V3. Sensory impairment of the opthalmic division was less common. CONCLUSIONS: These findings suggest that patients can tolerate perineural infiltration of the extracranial segment of the trigeminal nerve by NPC in the early stage of the disease when the tumor is still confined beneath the base of the skull. Dysfunction of the trigeminal nerve is closely related to perineural tumor invasion of the intracranial segment.
Adolescent↗
Post-operative pain control with topical steroid injection after hot dissection tonsillectomy.
Electrocautery excision (hot dissection) and scissor/snare dissection (cold dissection are two popular methods used in tonsillectomy. The former causes relatively more post-operative pain but takes less time to perform and is associated with less intra-operative and immediate post-operative bleeding than the latter. To explore post-operative pain control in patients undergoing electrodissection tonsillectomy, a prospective, randomized, one-blind study was designed involving local injections of steroid into the pillar and tonsil bed. The pain levels among the topical injection, deltoid muscle injection and the control group were scored and analyzed. Local steroid injection was found to significantly abate the post-tonsillectomy pain.
Adolescent↗
Nasopharyngeal tuberculosis.
Tuberculosis of the nasopharynx is uncommon and may mimic malignant disease. In this study, 14 patients (17-61 years old; 12 women, 2 men) who were histologically diagnosed as having nasopharyngeal tuberculosis were described. None of them bad known previous history of tuberculosis. Half of our patients had isolated nasopharyngeal tuberculosis with no apparent pulmonary involvement. Eleven patients present with enlarged neck lymph nodes and 6 of the 14 had blood-tinged nasal discharge. A bulging mass, with or without ulceration was the most common nasopharyngeal lesion encountered in 11 patients. Clinically, it appeared to resemble cancer presenting as a nasopharyngeal mass lesion with concomitant enlarged neck lymph nodes. It is important to consider tuberculosis in the differential diagnosis of nasopharyngeal lesions and take biopsy specimens for histological and bacteriological studies.
Adolescent↗
Assessment of skull base involvement in nasopharyngeal carcinoma: comparisons of single-photon emission tomography with planar bone scintigraphy and X-ray computed tomography.
The diagnostic contribution of single-photon emission tomography (SPET) to the detection of bone lesions of the skull base was explored in 200 patients with nasopharyngeal carcinoma (NPC). Comparison of SPET with planar bone scintigraphy showed that SPET improved the contrast and better defined the lesions in 107 out of the 200 patients. Comparison of SPET with X-ray computed tomography (CT) showed that SPET did not miss the lesions detected by CT while CT missed 49% of the lesions detected by SPET. The only false-positive lesion with SPET was detected in the mastoid bone. SPET detected skull base lesions in all of the 35 patients with cranial nerve involvement, while CT missed eight and planar bone scintigraphy missed four. The findings suggest that SPET should be included in the routine check-up examinations of patients with NPC.
Female↗
The fabricated radial forearm flap in pharyngolaryngeal surgery: saliva leakage and its prevention.
Reconstruction of the circular pharyngo-oesophageal defect continues to represent a formidable challenge for the head and neck surgeon. The fabricated radial forearm flap can provide thin and pliable skin and has potential in this one-stage reconstructive surgery. However, major problems with this technique are saliva leakage, fistula formation and stricture of the oesophageal anastomosis. Our experience with this flap for 11 pharyngo-oesophageal reconstructions has given us a better understanding of how to prevent these complications. Fistula formation and stricture were problems in our first two cases. With the 9 following cases, prevention of these complications was achieved by positioning the T-shaped suture lines of the tubed flap posteriorly. Our results suggest that adequate protection of the T-shaped suture lines during fabrication and anastomosis of the forearm flap is important in the prevention of saliva leakage.
Adult↗
Valve section of the eustachian tube.
Research on the eustachian tube (ET) and related paratubal structures was carried out by serial section of the temporal bone-ET specimens. In the cadaveric studies, the mid-cartilaginous section of the ET presented a curved slit-like lumen. It is believed that this section functions principally as a valve mechanism and acts like an active sphincter of the ET. This report illustrates the dynamic movement of the valve section in a living ET which can be observed by using a superfine fibreoptic videomicroendoscope. Disorders of the open-close mechanism of the valve section in a diseased ET due to different aetiologies are also discussed. This study indicated that transtympanic ET microendoscopy had considerable potential for exploring fascinating new aspects of the physiology, pathophysiology and anatomy dynamics of the ET.
Adult↗
Performance of older adults with and without cerebrovascular accident on the test of visual-perceptual skills.
OBJECTIVES: The purposes of this study were to (a) investigate whether older subjects with brain damage score lower on the Test of Visual-Perceptual Skills (TVPS) than control subjects without brain damage matched for age and education, (b) determine the demographic effects on test performance in both groups, and (c) determine the capacity of TVPS in identifying visual-perceptual deficits in adults with brain damage. METHOD: The study sample consisted of 22 subjects with cerebrovascular accident (CVA) and 155 subjects who were neurologically intact (control group). The TVPS was administered individually to each subject. Raw scores (total response time and accuracy) were analyzed to generate descriptive statistics. Other statistical analysis included analysis of variance, analysis of covariance, discriminant analysis, and Pearson product-moment correlations. RESULTS: There were significant between-group differences on all TVPS measures, with control subjects performing better than subjects with CVA. Age was shown to affect performance on most subtests of the TVPS in the control group. Education had significant influence over each measure, whereas gender differences were significant only in two subtests. No demographic effects were found in the group with CVA. The total TVPS accuracy score was the most powerful discriminator between the two groups, correctly classifying 74.4% of the subjects. Finally, the total accuracy score inversely correlated with total time score. CONCLUSION: The TVPS may be useful in screening for visual-perceptual impairments in adults with CVA. Age, gender, and educational level have no significant impact on the magnitude of visual-perceptual dysfunctions.
Age Factors↗
Transtympanic microendoscopy of the eustachian tube: a new approach method.
The eustachian tubes (ET) of sixteen patients suffering from chronic otitis media or otitis media with effusion were observed transtympanically by using an 0.85mm tip-controllable fiberoptic microendoscope. The examination was accomplished under local anesthesia. The osseous portion of ET was endoscopically accessible and was usually found patent in most patients. Similar to findings of the cadaveric temporal bone studies, a collapsed wall was observed in the lumen of isthmus and valve section of cartilaginous ET. The parapharyngeal section of cartilaginous ET, however, was found to include an open lumen, where pulsatile movements of the medioinferior membranous ET wall could be seen. In addition, special endoscopic findings of the ET lumen in different patients including relatively narrow isthmus, mucus accumulation, edematous mucosa, intraluminal tumor invasion, opening failure of valve section, etc. were also observed. Despite the technical difficulties involved, transtympanic ET microendoscopy is a potentially useful technique for exploring the physiology and pathophysiology of ET.
Adult↗