Neuromodulation for Treatment of Tinnitus: A Systematic Review and Meta-Analysis

OBJECTIVE

To evaluate the treatment efficacy of neuromodulation versus sham for the treatment of tinnitus.

DATA SOURCES

Cochrane Library, CINAHL, PubMed, Scopus.

REVIEW METHODS

The Cochrane Library, CINAHL, PubMed, and Scopus were searched from inception through May 2023 for English language articles documenting "neuromodulation" and "tinnitus" stratified by sham-controlled randomized control trials with 40 or more patients. Data collected included Beck Anxiety Inventory, Beck Depression Inventory (BDI), Tinnitus Handicap Inventory (THI), Tinnitus Questionnaire, and Visual Analog Scale. A Meta-analysis of continuous measures (mean) and proportions (%) were conducted.

RESULTS

A total of 19 randomized control trials (N = 1186) were included. The mean age was 48.4 ± 5.3 (range: 19-74), mean duration of tinnitus was 3.8 ± 3.4 years, 61% [56.2-65.7] male, and 55.7% [46-65] with unilateral tinnitus. The short-term effect of transcutaneous electrical nerve stimulation and transcranial direct current stimulation on THI score is -16.2 [-23.1 to -9.3] and -19 [-30.1 to -7.8], respectively. The long-term effect of repetitive transcranial magnetic stimulation on THI score is -8.6 [-11.5 to -5.7]. Transcranial direct current stimulation decreases BDI score by -11.8 [-13.3 to -10.3].

CONCLUSION

As measured by the Tinnitus Handicap Index, our findings suggest the effects of transcutaneous electrical nerve stimulation and transcranial direct current stimulation reach significant benefit in the short term, whereas repetitive transcranial magnetic stimulation reaches significant benefit in the long term. Based on the BDI, transcranial direct current stimulation significantly reduces comorbid depression in patients with tinnitus.

Treatment of frozen shoulder by manipulation under anaesthetic and injection: does the timing of treatment affect the outcome?

The effect of timing of a manipulation under anaesthetic (MUA) and injection of corticosteroid and local anaesthetic for the treatment of frozen shoulder has attracted little attention to date. All studies describe a period of conservative treatment before proceeding to an MUA. Delay has been associated with a poorer outcome. We present a retrospective review of a prospectively collected, single-surgeon, consecutive series of 246 patients with a primary frozen shoulder treated by MUA within four weeks of presentation. The mean duration of presenting symptoms was 28 weeks (6 to 156), and time to initial post-operative assessment was 26 days (5 to 126). The Oxford shoulder score (OSS) improved by a mean of 16 points (Wilcoxon signed-ranks test, p < 0.001) with a mean OSS at this time of 43 (7 to 48). Linear regression analysis showed no correlation between the duration of presenting symptoms and OSS at initial follow-up (R2 < 0.001) or peri-operative change in OSS (R2 < 0.001) or OSS at long-term follow-up (R2 < 0.03). Further analysis at a mean of 42 months (8 to 127) revealed a sustained improvement with a mean OSS of 44 (16 to 48). A good outcome follows an MUA and injection of corticosteroid and local anaesthetic in patients with primary frozen shoulder, independent of the duration of the presenting symptoms, and this improvement is maintained in the long term.

Young people of minority ethnic origin in England and early parenthood: views from young parents and service providers

The paper explores the phenomenon of early parenthood in minority ethnic communities in England. The data were collected using focus group interviews, in-depth semi-structured interviews and a telephone survey. The sample consisted of 139 participants (41 service providers, 10 grandmothers, 88 young parents). The findings map out the complexity and diversity of experience of early parenthood amongst young people of minority ethnic origin, not least the multiple attachments many experience in relation to their social groups, religious affiliations and the traditional patterns of parenting within their immediate and extended family. Both the young parents and professionals in this study constructed early parenthood in more positive terms than is currently portrayed in the contemporary policy. The findings are analysed and discussed in relation to ethnic identity, social inclusion and exclusion. We explore participants' attempts to counter negative 'deficit' models of early parenthood with reference to perspectives on youth, parenthood and contemporary strategic policy. In conclusion, we suggest an unambiguous focus on the reduction of pregnancy is not a credible message when teenage pregnancy is a social norm for a particular ethnic or cultural group. For young parents of Muslim faith in particular, teenage parenting within marriage is not necessarily considered a 'problem' or seen as a distinctive event. Most participants did not view early parenthood as a barrier to re-establishing career and educational aspirations. A wide diversity of experience amongst young parents is evidenced in the communities studied; this needs to be reflected more comprehensively both in UK policy and in support services.

Some current research in rotating-disc systems

Rotating-disc systems are used to model the flow and heat transfer that occurs inside the cooling-air systems of gas-turbine engines. In this paper, recent computational and experimental research in three systems is discussed: rotor-stator systems, rotating cavities with superposed flow and buoyancy-induced flow in a rotating cavity. Discussion of the first two systems concentrates respectively on pre-swirl systems and rotating cavities with a peripheral inflow and outflow of cooling air. Buoyancy-induced flow in a rotating cavity is one of the most difficult problems facing computationalists and experimentalists, and there are similarities between the circulation in the Earth's atmosphere and the flow inside gas-turbine rotors. For this case, results are presented for heat transfer in sealed annuli and in rotating cavities with an axial throughflow of cooling air.

Soft-copy quality control of digital spot images obtained by using X-ray image intensifiers

PURPOSE

To evaluate 12 x-ray image intensifier (XRII) digital spot systems.

MATERIALS AND METHODS

Four objective tests were performed to assess XRII digital spots: entrance exposure, patient exposure, soft-copy gray scale, and pixel noise. Two additional tests were performed to assess high-contrast limiting resolution and threshold contrast detection.

RESULTS

Digital spot XRII entrance exposures averaged 1 x 10(-7) C/kg (0.38 mR) for units with large fields of view (FOVs); mean entrance exposure in a medium-sized patient was 1. 25 x 10(-5) C/kg (48 mR). Luminance measurements of the table-side monitors provided a mean of 473 just-noticeable differences in gray scale with the room lights off. Mean resolution with a bar test pattern was measured as 1.5 line pairs per millimeter for systems with a 40-cm FOV. Measured pixel noise (in relative units) was 6-25. Mean threshold contrast with the lights off was 0.85%.

CONCLUSION

Once input exposure is normalized for FOV and image matrix size, soft-copy assessment of limiting resolution with either low-contrast detection or, preferably, an off-line noise metric (pixel SD) provides objective measurements of digital spot image quality. With the lights on, 10 systems with room-light sensors had an 11% loss of gray scale. For systems without sensors, the loss was 33%.

Inhibition of the K+ channel kv1.4 by acidosis: protonation of an extracellular histidine slows the recovery from N-type inactivation

1. Acidosis alters the transient outward current, ito, in the heart. We have studied the mechanism underlying the effect of acidosis on one of the K+ channels, Kv1.4 (heterologously expressed in Xenopus laevis oocytes), known to underlie ito. 2. At pH 6.5, wild-type Kv1.4 current was inhibited during repetitive pulsing, in part as a result of a slowing of recovery from N-type inactivation. 3. Acidosis still caused slowing of recovery after deletion of just one (either the first or second) of the N-terminal inactivation ball domains. However, deletion of both the N-terminal inactivation ball domains greatly reduced the inhibition. 4. As well as the N-terminus, other parts of the channel are also required for the effect of acidosis, because, whereas the transfer of the N-terminus of Kv1.4 to Kv1.2 conferred N-type inactivation, it did not confer acidosis sensitivity. 5. Replacement of an extracellular histidine with a glutamine residue (H508Q) abolished the slowing of recovery by acidosis. Reduction of C-type inactivation by raising the bathing K+ concentration or by the mutation K532Y also abolished the slowing. 6. It is concluded that binding of protons to H508 enhances C-type inactivation and this causes a slowing of recovery from N-type inactivation and, thus, an inhibition of current during repetitive pulsing.

Active matrix liquid crystal displays for clinical imaging: comparison with cathode ray tube displays

Fifteen large-area, flat-panel displays used for clinical image review were evaluated for image quality and compared with 30 comparably sized cathode ray tube (CRT) monitors. Measurements were of image display patterns by Video Electronic Standards Association (VESA) and a commercial product. Field measurements were made of: maximum and minimum luminance, ambient lighting, characteristic curve (gamma), point shape and size, high-contrast resolution, uniformity, and distortion. Assessments were made of pixel defects, latent image patterns, ghosting artifacts, and viewing angle luminance. Also, a questionnaire was generated for users of the flat-panel and CRT units. Seventeen respondents indicated no preference for either flat panel or CRT. Results show these flat panels to have higher luminance (mean, 177.7 cd/m2); larger number of just noticeable differences (JNDs; n = 555), higher gamma, comparable uniformity, and warm-up time. CRTs had less angle viewing dependence and far fewer artifacts (ghosting and latent images). Our questionnaire showed active matrix liquid crystal displays (AMLCD) to be fully acceptable for clinical image viewing. Furthermore, the statistical results show that further testing for new AMLCDs of this type is unwarranted.

Effect of extracellular cations on the inward rectifying K+ channels Kir2.1 and Kir3.1/Kir3.4

The effects of Ba2+, Mg2+, Ca2+ and Na+ as blocking ions were investigated in 90 and 10 mM extracellular K+ solutions on the cloned inward rectifying K+ channel Kir2.1 expressed in Xenopus oocytes. Some data were also obtained using another inward rectifying K+ channel Kir3.1/Kir3.4. The addition of Ba2+ caused a concentration-, voltage- and time-dependent block of both channels. Decreasing the extracellular K+ concentration augmented the block. The data suggest that Ba2+ blocks the channels by binding to a site within the channel pore and that the electrical binding distance, delta, of the site is significantly different for Kir2.1 and Kir3. 1/Kir3.4 (0.38 and 0.22, respectively). Mg2+ and Ca2+ caused an instantaneous concentration- and voltage-dependent block of both channels. With Kir2.1, decreasing the K+ concentration augmented the block. The voltage dependence of the block was less than that of Ba2+ ([delta], 0.1), indicating a more superficial binding site for these ions within the channel pore. The affinity of the channels for Mg2+ and Ca2+ was 1000-fold lower than that for Ba2+. Addition of Na+ resulted in a concentration-, voltage- and time-dependent block of Kir2.1, similar to that observed with Ba2+. The competition between the blocking cations (for Kir2.1: Ba2+, Mg2+, Ca2+; for Kir3. 1/Kir3.4: Ba2+) and extracellular K+ suggests that the binding sites for the blocking cations may be sites to which K+ binds as part of the normal passage of K+ through the channels. It is possible that under normal physiological conditions naturally occurring extracellular cations may partly block the two inward rectifying K+ channels.

Salicylhydrazine-containing inhibitors of HIV-1 integrase: implication for a selective chelation in the integrase active site

In previous studies we identified N,N'-bis(salicylhydrazine) (1) as a lead compound against purified recombinant HIV-1 integrase. We have now expanded upon these earlier observations and tested 45 novel hydrazides. Among the compounds tested, 11 derivatives exhibited 50% inhibitory concentrations (IC50) of less than 3 microM. A common feature for activity among these inhibitors is the hydroxyl group of the salicyl moiety. Although the active inhibitors must contain this hydroxyl group, other structural modifications can also influence potency. Removal of this hydroxyl group or replacement with an amino, bromo, fluoro, carboxylic acid, or ethyl ether totally abolished potency against integrase. Several asymmetric structures exhibited similar potency to the symmetric lead inhibitor 1. The superimposition of the lowest-energy conformations upon one another revealed three sites whose properties appear important for ligand binding. Site A is composed of the 2-hydroxyphenyl, the alpha-keto, and the hydrazine moieties in a planar conformation. We propose that this site could interact with HIV-1 integrase by chelation of the metal in the integrase active site as inhibition of HIV-1 integrase catalytic activity and DNA binding were strictly Mn2+-dependent. The hydrophobic sites B and C are probably responsible for complementarity of molecular shape between ligand and receptor. Our data indicate that only those compounds which possessed sites A, B, and C in a linear orientation were potent inhibitors of HIV-1 integrase. Although all the active inhibitors possessed considerable cytotoxicity and no apparent antiviral activity in CEM cells, the study presents useful information regarding ligand interaction with HIV-1 integrase protein.

Highly potent synthetic polyamides, bisdistamycins, and lexitropsins as inhibitors of human immunodeficiency virus type 1 integrase

Alignment of the available human immunodeficiency virus type 1 (HIV-1) viral DNA termini [U5 and U3 long terminal repeats (LTRs)] shows a high degree of conservation and the presence of a stretch of five or six consecutive adenine and thymine (AT) sequences approximately 10 nucleotides away from each LTR end. A series of AT-selective minor-groove binders, including distamycin and bisdistamycins, bisnetropsins, novel lexitropsins, and the classic monomeric DNA binders Hoechst 33258, 4'-diamino-2-phenylindole, pentamidine, berenil, spermine, and spermidine, were tested for their inhibitory activities against HIV-1 integrase (IN). Although netropsin, distamycin, and all other monomeric DNA binders showed weak activities in the range of 50-200 microM, some of the polyamides, bisdistamycins, and lexitropsins were remarkably active at nanomolar concentrations. Bisdistamycins were 200 times less potent when the conserved AAAAT stretch present in the U5 LTR was replaced with GGGGG, consistent with the preferred binding of these drugs to AT sequences. DNase I footprinting of the U5 LTR further demonstrated the selectivity of these bisdistamycins for the conserved AT sequence. The tested compounds were more potent in Mg+2 than in Mn+2 and inhibited IN50-212 deletion mutant in disintegration assays and the formation of IN/DNA complexes. The lexitropsins also were active against HIV-2 IN. Some of the synthetic polyamides exhibited significant antiviral activity. Taken together, these data suggest that selective targeting of the U5 and U3 ends of the HIV-1 LTRs can inhibit IN function. Polyamides might represent new leads for the development of antiviral agents against acquired immune deficiency syndrome.

Regional differences in the role of the Ca2+ and Na+ currents in pacemaker activity in the sinoatrial node

The effect of block of the L-type Ca2+ current by 2 microM nifedipine and of the Na+ current by 20 microM tetrodotoxin on the center (normally the leading pacemaker site) and periphery (latent pacemaker tissue) of the rabbit sinoatrial node was investigated. Spontaneous action potentials were recorded with microelectrodes from either an isolated right atrium containing the whole node or small balls of tissue (approximately 0.3-0.4 mm in diameter) from different regions of the node. Nifedipine abolished the action potential in the center, but not usually in the periphery, in both the intact sinoatrial node and the small balls. Tetrodotoxin had no effect, on electrical activity in small balls from the center, but it decreased the takeoff potential and upstroke velocity and slowed the spontaneous activity (by 49 +/- 10%; n = 11) in small balls from the periphery. It is concluded that whereas the L-type Ca2- current plays an obligatory role in pacemaking in the center, the Na+ current plays a major role in pacemaking in the periphery.

Disinfection of farrowing pens

The author presents details on the cleaning and disinfection of specialised farrowing accommodation within an intensive pig unit. Procedures are described for use in two quite different sets of circumstances, as follows: in the event of the occurrence of one of the major notifiable epizootic diseases; routine cleaning and disinfection as part of normal management procedures. In the former case, herd slaughter and the cleaning and disinfection of premises are required by law, in accordance with the protocol adopted by international agreement with reference to the specific disease concerned. In the latter case, cleaning and disinfection are not governed by statutes, and the protocol is established to suit the requirements of the individual unit, under the supervision of the farmer and the veterinary adviser.

The antimicrobial susceptibility of Chlamydia trachomatis in cell culture

The action of 22 antimicrobial agents against the SA2f strain of Chlamydia trachomatis has been studied by the use of a simple cell culture technique. Tests for bactericidal activity were undertaken with some of the agents, and latency of infection was demonstrated. The susceptibilities of 10 clinical strains of C. trachomatis and of SA2f to oxytetracyline, erythromycin, and spectinomycin in cell culture were found to be identical.

Liver fluke infection in horses and ponies

Thirty eight cases of Fasciola hepatica infection in horses with associated clinical signs are reported. A method of examining large amounts of faeces for fluke is described. A safe method of treatment for infected horses is given which involves oral medication with oxyclozanide at a dose rate of 15 ml/50 kg body weight.

Studies on the nutrition of marine flatfish. The effect of different dietary fatty acids on the growth and fatty acid composition of turbot (Scophthalmus maximus)

1. Five groups of juvenile turbot (Scophthalmus maximus) which had been given a diet free of fat for 12 weeks were given diets in which the lipid component (g/kg) was: oleic acid alone 50, oleic acid 40+linoleic acid 10, oleic acid 40+linolenic acid 10, oleic acid40+arachidonic acid 10 or oleic acid 40+cod-liver oil 10. These five experimental diets were given for 16 weeks. 2. Weight gains were highest in the group given the diet containing cod-liver oil and lowest in the groups given diets containing oleic acid alone or oleic acid+linoleic acid. Weight gains in the groups given oleic acid+arachidonic acid or linolenic acid were markedly inferior to those of the group given oleic acid+cod-liver oil. It is concluded that arachidonic acid is inferior to polyunsaturated fatty acids of the omega3 series in maintaining growth rate in turbot. 3. Fatty acid analyses of neutral lipids and phospholipids of liver and extrahepatic tissues did not suggest any evidence of desaturation of dietary oleic acid, linoleic acid or linolenic acid by the turbot. These experiments confirm previous isotopic evidence that turbot lack the necessary microsomal desaturases to perform this metabolic transformation.

Elongation and desaturation of dietary fatty acids in turbot Scophtalmus maximus L., and rainbow trout, Salmo gairdnerii rich

Turbot and rainbow trout, which had previously recieved diets free of fat, were fed [1-14C] fatty acids. The distribution of radioactivity in the tissue fatty acids was examined 6 days later. In rainbow trout fed [1-14C] 18:3omega3, 70% of the radioactivity was present in 22:6omega3 fatty acid. In contrast, turbot fed [1-14C] 18:1omega9, 18:2omega6, or 18:3omega3 converted only small amounts of labeled fatty acids (3-15%) into fatty acids of longer chain length. The major product of the limited modification found in turbot was the dietary acid elongated by 2 carbon atoms.

Abnormal flexion of the corono-pedal joint or "contracted tendons" in unweaned foals

A condition frequently misnamed "contracted tendons" is described in unweaned foals. Various theories regarding its aetiology are examined. Overfeeding and lack of exercise are suggested as being the most likely causes, leading to excessive growth of the long bones. An effective method of treatment is described. "Contracted tendons" in yearlings are also discussed.