The effect of combined spinal‐epidural (CSE) anaesthesia and size of spinal needle on postoperative hearing loss after elective caesarean section

The effect of combined spinal epidural (CSE) anaesthesia and size of spinal needle on postoperative hearing loss after elective caesarean section The exact aetiology of vestibulocochlear dysfunction after spinal anaesthesia is unknown. Low‐frequency hearing loss occurs after spinal anaesthesia. The aim of this study was to investigate the effects of combined spinal–epidural (CSE) anaesthesia and size of spinal needle on vestibulocochlear dysfunction, using pure tone audiometry performed pre‐ and on the first and the second day postoperatively. Forty‐five patients who were to undergo elective caesarean section were evaluated. In group I, CSE anaesthesia (18 G Tuohy, 25 G Whitacre pencil‐point‐design spinal needles) was performed in 15 patients. In group II, spinal anaesthesia was performed in 15 patients with 25 G Whitacre pencil‐point‐design spinal needles and, in group III, spinal anaesthesia was performed in 15 patients with 22 G Whitacre pencil‐point‐design spinal needles. In the pre‐ and on the first and the second day postoperatively, the pure tone audiogram was performed in the audiology laboratory of our hospital, using a calibrated Kamplex Diagnostic Audiometer AC 40 in a noise‐free room. When the CSE anaesthesia group and 22 G spinal group were compared for change in hearing between the pre‐ and postoperative periods, a statistically significant difference was observed at R‐right ear 125 Hz (P < 0.025) and at L‐left ear 125 Hz (P < 0.023), and at L‐left ear 1000 Hz (P < 0.036) and at R‐right ear 1500 Hz (P < 0.006), and at L‐left ear 1500 Hz (P < 0.022). At other frequencies, the difference was insignificant. When the CSE anaesthesia group and 25 G spinal group were compared for change in hearing between the pre‐ and postoperative periods, no statistically significant difference was detected at any frequency tested. When 22 G spinal group and 25 G spinal group were compared for change in hearing between the pre‐ and postoperative periods, there was some hearing loss at low frequency, although this difference did not reach statistical significance. The positive correlation of low‐frequency hearing loss and increased pressure in the epidural space (which decrease the risk of cerebrospinal fluid leakage through the dura) suggests that cerebrospinal fluid leakage via the spinal puncture hole is not the only factor involved. Perioperative fluid replacement alone may not prevent hearing loss but CSF loss through the dural puncture site should also be prevented.     

The effect on the middle-ear cavity of an absorbable gelatine sponge alone and with corticosteroids

The objectives of this study were to establish whether there is an obvious difference between intact mucosa and abraded mucosa of the middle-ear cavity in respect to the potential side effects from the application of absorbable gelatine sponge (Gelfoam) and to investigate if Gelfoam combined with corticosteroid ointment (cortimycine, sterile 1% hydrocortisone acetate) can reduce the occurrence of these effects. Twenty Albino rats were used in the study. These animals were divided into four groups, with ten ears in each group. In group A, the middle-ear mucosa was kept intact, and Gelfoam was inserted into the middle-ear cavity. In group B, the middle-ear mucosa was abraded, and Gelfoam was inserted. In group C, Gelfoam with corticosteroid was implanted over the intact mucosa, and in group D, the mucosa was abraded prior to the insertion of Gelfoam with corticosteroid. The changes were evaluated 8 weeks postoperatively. In group A, there was a minimal increase in fibroblastic activity, vascular proliferation with mild to moderate fibrosis and all but two tympanic membranes were perfectly normal. However, in group B, we encountered a significant increase in fibroblastic activity, vascular proliferation and fibrosis, and we observed that all tympanic membranes were moderately to severely thickened. These histopathologic changes related to Gelfoam were noted to be decreased in group C and especially in group D. As previously reported in the literature, Gelfoam was found to promote the formation of connective tissue in the middle-ear cavity regardless of the status of the mucosa. The unwanted effects of this material may be decreased if it is combined with corticosteroids in the middle-ear cavity.     

Augmentation of Shoulder Contour Using a Calf Implant

Sprengel deformity is a rare orthopedic condition that is associated with functional and cosmetic impairment. Results of orthopedic procedures are usually inconsistent and cosmetic results are far from satisfactory in these patients. A silicone-gel-filled calf prosthesis was used to correct the shoulder contour in a patient with Sprengel deformity. Cosmetically the deformity can be restored by using a calf implant for patients in whom orthopedic procedures are not likely to yield a satisfactory outcome.     

The effect of chronic restraint stress and sulfite on visual evoked potentials (VEPs): relation to lipid peroxidation.

Stress and sulfite can stimulate numerous pathways leading to an increased production of free radicals which generate a peroxidation cascade producing lipid peroxidation, protein oxidation, DNA damage and cell death, and contribute to the occurrence of pathologic conditions. The purpose of our study was to investigate the effects of stress and sulfite on visual evoked potentials (VEPs) and to examine the relationship between lipid peroxidation and VEP changes. Forty male wistar rats, aged three months were used. They were equally divided into four groups: control (C), the group exposed to restraint stress (R), the group treated with sulfite (S) and the group exposed to stress and treated with sulfite (RS). Chronic restraint stress was applied for 21 days (1h/day) and sodium metabisulfite (520 mg/kg/day) was given by gavage for the same period. All latencies of VEP components were prolonged in the R, S and RS groups with respect to the C group. Brain and retina TBARS levels were found to be increased in those groups compared to the C group. Our results strongly suggest that the latency prolongations of all VEP components may have resulted from the enhancement of lipid peroxidation. Correlation analysis between brain and retina TBARS levels and VEP latencies also support this conclusion. Our data in regard to latency prolongations of all VEP components in the stress group exposed to sulfite, reflected an additive effect of sulfite toxicity on VEP components. Therefore it could be suggested that chronic exposure to stress and sulfite together is associated with a considerable health risk.     

Segmental myoclonus as the presenting symptom of an acute disseminated encephalomyelitis: a case report.

Segmental myoclonus is described as the involuntary contractions of contiguous muscles innerved by the brain stem or by spinal cord. The underlying causes of segmental myoclonus in children are demyelinating diseases and intrinsic tumors. Here, we report a case who was presented with segmental myoclonus on his left arm and later diagnosed as atypical monosymptomatic presentation of acute disseminated encephalomyelitis (ADEM). The case represents the first in the literature in which ADEM is considered as the possible cause of segmental myoclonus. Our findings demonstrate that: (i) in focal movement disorders such as segmental myoclonus, a careful neuroradiological examination of the neuroanatomical region for the possible presence of organic lesions might be rewarding, (ii) ADEM might be one of the potentially reversible causes of myoclonus.     

Effect of water extract of Turkish propolis on tuberculosis infection in guinea-pigs.

Mycobacterium tuberculosis (H(37)R(v))-infected guinea-pig model was used to investigate the effect of water extract of propolis (WEP). After subcutaneous inoculation of tubercle bacilli, each animal received oral WEP (n=9), isoniazid (n=5) or saline (n=6) as placebo and were sacrificed 30 days later. Formation of necrosis was less prominent in the group treated with WEP, but was not statistically significant (P>0.05). The granuloma formation in the same group was more prominent than the placebo and isoniazid groups; however, this finding failed to reach statistical significance by the Kruskal-Wallis test (P>0.05). These findings suggest that Turkish WEP may have a limited effect on the development of tuberculosis infection in this guinea-pig model.     

Present and Theoretical Applications of Poly-Ether-Ether-Ketone (PEEK) in Orthodontics: A Scoping Review

Background: During the last decade, there has been an increased demand for non-metallic materials in orthodontics due to allergies, compatibility with medical imaging devices such as MRI, and aesthetic reasons. Monolithic poly-ether-ether-ketone material could address medical issues such as allergies and MRI compatibility. Moreover, nickel–titanium (NiTi) archwires covered in PEEK, either by a tube or electrophoretic deposition, could address esthetic concerns. This scoping review aims to summarize the available evidence in the literature to provide an overview of the applications and material properties of PEEK in orthodontics. Methods: This scoping review was conducted according to the Joanna Briggs Institute Manual for Evidence Synthesis for scoping reviews and the Preferred Reporting Items for Systematic Review and Meta-Analyses Protocols extension for Scoping Reviews (PRISMA-ScR). We searched for relevant publications in MEDLINE (via PubMed), Embase, Web of Science, Cochrane Library, CENTRAL, ProQuest, and SCOPUS. A gray literature search was conducted on Google Scholar. Results: Six studies were included. In three studies, the authors investigated the feasibility of developing a composite PEEK-NiTi wire, while in two other studies, the authors investigated the feasibility of monolithic PEEK wires. In the final study, the authors investigated the feasibility of PEEK as a bonded retainer. Conclusions: The included studies show promising results in developing monolithic and composite (PEEK-NiTi) materials. Further research on the robustness of PEEK composites in the oral cavity, the status of cytotoxicity and roughness values, and the (bio)-mechanical behavior of the composites is needed. A homogenously set up comparative study of clinically relevant, evenly sized, monolithic PEEK wires versus conventional orthodontic wires for their biomechanical, mechanical, and material properties would clarify the possibilities of developing monolithic PEEK wires. Missing data in the retainer study suggest more research on the mechanical properties and points of failure of PEEK-bonded retainers, and a comparative study comparing the failure and mechanical properties of PEEK-bonded retainers to flat braided metallic bonded retainers is needed.     

The possible mechanisms of protocatechuic acid-induced central analgesia

It is aimed to investigate the central antinociceptive effect of protocatechuic acid and the involvement of stimulation of opioidergic, serotonin 5-HT_2A/2C, α2-adrenergic and muscarinic receptors in protocatechuic acid-induced central analgesia in mice. Time-dependent antinociceptive effects of protocatechuic acid at the oral doses of 75, 150 and 300?mg/kg were tested in hot-plate (integrated supraspinal response) and tail-immersion (spinal reflex) tests in mice. To investigate the mechanisms of action; the mice administered 300?mg/kg protocatechuic acid (p.o.) were pre-treated with non-specific opioid antagonist naloxone (5?mg/kg, i.p.), serotonin 5-HT_2A/2C receptor antagonist ketanserin (1?mg/kg, i.p.), α2-adrenoceptor antagonist yohimbine (1?mg/kg, i.p.) and non-specific muscarinic antagonist atropine (5?mg/kg, i.p.), respectively. The antinociceptive effect of protocatechuic acid was observed at the doses of 75, 150 and 300?mg/kg in tail-immersion test, at the doses of 150 and 300?mg/kg in hot-plate test at different time interval. The enhancement in the latency of protocatechuic acid-induced response to thermal stimuli was antagonized by yohimbine, naloxone and atropine in tail-immersion test, while it was antagonized only by yohimbine and naloxone pretreatments in hot-plate test. These results indicated that protocatechuic acid has the central antinociceptive action that is probably organized by spinal mediated cholinergic and opiodiergic, also spinal and supraspinal mediated noradrenergic modulation. However, further studies are required to understand how protocatechuic acid organizes the interactions of these modulatory systems. As a whole, these findings reinforce that protocatechuic acid is a potential agent that might be used for pain relief. Additionally, the clarification of the effect and mechanisms of action of protocatechuic acid will contribute to new therapeutic approaches and provide guidance for new drug development studies.     

The role of endometrium in endometriosis

Endometriosis is defined as the presence of endometrial glands and stroma outside the uterus. Several theories have been proposed to explain the pathogenesis of this disease. According to Sampson's retrograde menstruation theory, endometrial cells are refluxed through the fallopian tubes during the menstruation and implant onto peritoneum or pelvic organs. Since retrograde menstruation is a very common phenomenon among women of reproductive age, there must be other factors that may contribute to the pathophysiology and/or pathogenesis of endometriosis. Genetic predisposition, environmental factors, and alterations in immune and endocrine functions are believed to play significant roles in the establishment and maintenance of endometriosis. Although the eutopic endometriums of women with and without endometriosis are histologically similar, studies revealed that there are many fundamental differences between these two tissues. Invasive properties, decreased apoptosis, alterations in expression of specific gene and proteins, and increased steroid and cytokine production have been identified in eutopic endometrium of women with endometriosis. Furthermore, significant biochemical differences exist even between ectopic and autologous eutopic endometrium. These differences can be explained by the direct effects of an inflammatory peritoneal environment.