The Prevalance of Congenital Optic Disc Anomalies in Turkey: A Hospital-Based Study

Purpose: The aim of this study was to investigate the prevalance of congenital optic disc (OD) anomalies in Turkey. Methods: The 11149 eyes of 5583 patients were screened for OD anomalies. All patients were underwent a complete ophthalmic examination including best corrected visual acuity, refraction, spherical equivalent, slit lamp biomicroscopy, intraocular pressure measurements, dilated stereoscopic fundus examination. Data analyses were performed by using SPSS for Windows, version 22.0 (SPSS Inc., Chicago, IL, United States).Results: 11149 eyes of 5583 participants were screened. Of the 5583 participants who underwent OD examination, 186 (3,3%) were found to be abnormal. 266 of 11149 (2,38%) eyes were found OD anomalies. 98 (52,7%) were female, 88 (47,3%) were male and the mean of age was 44,05±15,73 years. The prevalence of all congenital OD anomalies was found 3,3%. The tilted disc was the most common anomaly and was found at least one eye in 46 patients (75 eyes) and 0.82% of all screened patients. Peripapillary myelinated nerve fibres was the second common anomaly and was found at least one eye in 29 subjects (35 eyes) and 0,51% of all screened subjects. Peripapillary atrophy was the third common anormality, and was found in at least one eye in 24 patients (37 eyes) and 0,42% of all screened subjects.Conclusion: To our knowledge, this is the first study that the prevalences of all congenital optic disc anomalies from Turkey. The prevalence of congenital optic disc anomalies is higher than in other countries.

Comportamento de tecidos à implantação de partículas esféricas de limalha

Introduction os spherical alloys particles (size range from 15 to 70 micra) in the back at the level of the first thoracic vertebra of 24 male rats, 60 days old, for a period of time of 12, 13, 14 and 15 months, shows no alteration in the connective tissue, striate muscle, fatty tissue, brown fatty tissue, nerve fibres and hair follicle.

Strength exercise for balance and gait in HIV-associated distal symmetrical polyneuropathy: A randomised controlled trial

Background: HIV-associated peripheral neuropathy (PN) is a common neurological complication associated with HIV infection. Distal symmetrical polyneuropathy (DSPN) is the most commonly occurring type, which is associated with symptoms such as numbness, unsteady gait and, in some cases, muscle atrophy and weakness when myelinated nerve fibres are affected. If unmyelinated nerve fibres are affected, a painful neuropathy and autonomic symptoms may occur.Objectives: This research study assessed the effects of a strength exercise intervention on balance impairment and gait disturbance amongst individuals living with HIV-associated DSPN.Method: The study was a single-blinded, randomised controlled trial (RCT) with participants sourced from four HIV centres in Kano metropolis, Nigeria. The intervention was supervised and included progressive resistance exercise (PRE) (three 40-min sessions per week for 12 weeks) using a quadriceps bench (n = 44). The control group (CG) included the non-exercise group (n = 47). The two groups continued to receive routine care. Data were summarised and analysed using inferential statistics (SPSS version 20 program) with the alpha level set at 0.05.Results: At 12 weeks, the results revealed significant improvement with regard to balance performance (p = 0.001) and walking ability (p = 0.001) in the training group. In contrast, no significant differences in balance (P = 0.677) or gait (P = 0.578) were observed in the CG.Conclusion: The findings suggest that PRE is beneficial for balance impairment and gait disturbance caused by neuropathy in persons living with HIV and receiving antiretroviral drugs.

THE PLASTICITY OF NERVE FIBRES: THE PROLONGED EFFECTS OF POLARIZATION OF AFFERENT FIBRES

The review surveys various aspects of the plasticity of nerve fibres, in particular the prolonged increase in their excitability evoked by polarization, focusing on a long-lasting increase in the excitability of myelinated afferent fibres traversing the dorsal columns of the spinal cord. We review the evidence that increased axonal excitability (i) follows epidurally applied direct current as well as relatively short (5 or 10 ms) current pulses and synaptically evoked intrinsic field potentials; (ii) critically depends on the polarization of branching regions of afferent fibres at the sites where they bifurcate and give off axon collaterals entering the spinal grey matter in conjunction with actions of extrasynaptic GABAA membrane receptors; and (iii) shares the feature of being activity-independent with the short-lasting effects of polarization of peripheral nerve fibres. A comparison between the polarization evoked sustained increase in the excitability of dorsal column fibres and spinal motoneurons (plateau potentials) indicates the possibility that they are mediated by partly similar membrane channels (including non-inactivating type L Cav++ 1.3 but not Na+ channels) and partly different mechanisms. We finally consider under which conditions trans-spinally applied DC (tsDCS) might reproduce the effects of epidural polarization on dorsal column fibres and the possible advantages of increased excitability of afferent fibres for the rehabilitation of motor and sensory functions after spinal cord injuries.

Progression and regression of nerve fibre pathology and dysfunction early in diabetes over 5 years

It has been traditionally suggested that the early development of diabetic sensorimotor polyneuropathy (DSPN) is characterized by a predominant and progressive injury to small nerve fibres followed by large fibre impairment. We alternatively hypothesized that small and large fibre damage due to DSPN in type 1 and type 2 diabetes could develop in parallel and may not only be progressive but also reversible. Participants from the German Diabetes Study baseline cohort with recent-onset type 1/type 2 diabetes (n = 350/570) and age-matched glucose-tolerant control individuals (Control 1/Control 2: n = 114/190) were assessed by nerve conduction studies (NCS), thermal detection thresholds (TDT), vibration perception threshold (VPT), Neuropathy Symptom Score (NSS), Neuropathy Disability Score (NDS), and intraepidermal nerve fibre density (IENFD) in skin biopsies (type 1/type 2 diabetes: n = 102/226; Control 1/Control 2: n = 109/208). Subsets of participants with type 1/type 2 diabetes were followed for 5 years (n = 184/307; IENFD subset: n = 18/69). DSPN was defined by the Toronto Consensus criteria. At baseline, DSPN was present in 8.1 and 13.3% of the type 1 and type 2 diabetes groups, respectively. The most frequently abnormal tests in the lower limbs below or above the 2.5th and 97.5th centile of the controls were IENFD (13.7%) and individual NCS (up to 9.4%) in type 1 diabetes participants and IENFD (21.8%), malleolar VPT (17.5%), and individual NCS (up to 11.8%) in those with type 2 diabetes, whereas TDT abnormalities did not differ between the control and diabetes groups. After 5 years in type 2 diabetes participants, the highest progression rates from the normal to the abnormal range were found for IENFD (18.8%) by -4.1 ± 2.8 fibres/mm, malleolar VPT (18.6%) by 9.1 ± 20.2 µm, and NDS (15.0%) by 3.7 ± 1.5 points, while vice versa the highest regression rates were observed for NDS (11.2%) by -3.1 ± 1.3 points, sural nerve amplitude (9.1%) by 4.7 ± 3.0 µV, IENFD (8.7%) by 1.4 ± 1.3 fibres/mm, and NSS (8.2%) by -5.8 ± 1.6 points. In type 1 diabetes participants, no major progression was seen after 5 years, but subclinical DSPN regressed in 10.3%. These findings point to an early parallel damage to both small and large nerve fibres in well-controlled recent-onset type 2 and, to a lesser extent, type 1 diabetes. After 5 years peripheral nerve morphology and function and clinical measures progress to the abnormal range in type 2 diabetes, but initial nerve alterations are also reversible to a meaningful degree.

Cytotoxic Natural Killer Cells Disrupt Nerve Fibres Through Granzyme H in Atheriosclerotic Cerebral Small Vessel Disease

Background: Circulating natural killer cells (NK cells) are enriched in the central nervous system in atheriosclerotic cerebral small vessel disease (aCSVD) rat models, but their resulting effects and underlying mechanism remain to be investigated.Methods: A total of 32 patients with aCSVD and 28 healthy control patients were recruited for this study. According to white matter hyperintensity (WMH) burden, which is closely related to the severity of aCSVD, 20 participants were divided into two groups: burden of 0-1 (n=10) and burden of 2-3 (n=10). All participants participated in proteomics analysis of their cytotoxic NK cells and serum, and 3 participated in proteomics analysis of their cerebrospinal fluid (CSF). In vitro BBB models and a co-culture system with primary human neurons were utilized to verify the pathogenic behaviours of cytotoxic NK cells.Results: In aCSVD patients with a high WMH burden, integrin β2 (ITGB2), cathepsin D (CTSD) and granzyme H (GZMH) were highly expressed in cytotoxic NK cells. ITGB2 interacted with intercellular adhesion molecule 1 (ICAM1) in vascular endothelial cells and promoted the adhesion of cytotoxic NK cells in vitro. Moreover, inhibition of CTSD reduced the destruction of type IV collagen (COL4A) in the extracellular matrix of the BBB and the leakiness of the BBB in vitro and in vivo, indicating that synthetic CTSD in cytotoxic NK cells participates in BBB damage. After passing through the leaky BBB, GZMH disruption on demyelinated nerve fibres was reversed by cotreatment with the inhibitor 3,4-DCIC, suggesting that cytotoxic NK cell-released GZMH is crucial for the disruption of demyelinated nerve fibres during WMH in aCSVD.Conclusions: Cytotoxic NK cells contribute to the CTSD-induced damage to the BBB and GZMH-induced disruption of demyelinated nerve fibres during WMH in aCSVD. Our work highlights the important role of cytotoxic NK cells in the disruption of nerve fibres in patients with aCSVD with a high WMH burden for the first time.

Capsaicin 8% Patch Treatment in Non-Freezing Cold Injury: Evidence for Pain Relief and Nerve Regeneration

Introduction: Neuropathic pain associated with Non-freezing Cold Injury (NFCI) is a major burden to military service personnel. A key feature of NFCI is reduction of the intra-epidermal nerve fibre density in skin biopsies, in keeping with painful neuropathy. Current oral treatments are generally ineffective and have undesirable side effects. Capsaicin 8% patch (Qutenza) has been shown to be well-tolerated and effective for reducing neuropathic pain, for up to 3 months after a single 30-minute application.Methods: In this single-centre open label study, 16 military participants with NFCI (mean duration 49 months) received 30-minute Capsaicin 8% patch treatment to the feet and distal calf. Pain symptoms were assessed using a pain diary (with the 11-point Numerical Pain Rating Scale, NPRS) and questionnaires, the investigations included skin biopsies, performed before and three months after treatment.Results: Participants showed significant decrease in spontaneous pain (mean NPRS: −1.1, 95% CI: 0.37 to 1.90; p = 0.006), and cold-evoked pain (−1.2, 95% CI: 0.40 to 2.04; p = 0.006). The time-course of pain relief over 3 months was similar to other painful neuropathies. Patient Global Impression of Change showed improvement (p = 0.0001).Skin punch biopsies performed 3 months after the patch application showed significant increase of nerve fibres with structural marker PGP9.5 (intra-epidermal nerve fibres [IENFs], p < 0.0001; sub-epidermal nerve fibres [SENFs]; p =< 0.0001), and of regenerating nerve fibres with their selective marker GAP43 (p = 0.0001). The increase of IENFs correlated with reduction of spontaneous (p = 0.027) and cold-evoked pain (p = 0.019).Conclusions: Capsaicin 8% patch provides an exciting new prospect for treatment of NFCI, with regeneration and restoration of nerve fibres, for the first time, in addition to pain relief.

Tactile sensory control of the human hand

This chapter details the sensory input from the hand that is mediated by a system of fast-adapting and slowly adapting nerve fibres with a specific anatomical distribution and associations with particular sensory end organs that allow multimodal sensory input and processing. This highly refined system interacts with the motor system to provide continuous feedback that allows the dexterous manipulation of the environment that distinguishes the human hand.

Optical coherent tomography in the diagnosis of inflammatory and ischemic optical neuropathies (clinical cases)

Optic neuropathy is a group of diseases of the optic nerve. Using diagnostic techniques such as ophthalmoscopy and perimetry diagnosis are insufficient, as the found abnormalities are not specific for either inflammation or ischemia. Establishing the predominant factor in the pathogenesis of neuropathy is crucial in determining the method of treatment. The aim of the study: to investigate the features of optic nerve damage using optical coherent tomography (OCT) in optic neuropathy in the acute period. Materials and methods: two patients with visual impairment were examined. Result. Patient G. had concomitant rheumatoid arthritis with unregulated Methotrexate therapy. OCT revealed edema of the nerve fibre layer convinced of the predominance of inflammatory neuropathy (atypical neuritis). Pulse therapy with corticosteroids was prescribed, which gave a positive functional effect. A patient O. with pneumonia on the background of Covid-19 with a history of OST showed a decrease in the thickness of the layer of nerve fibres in the lower segment, and in the angio mode – drusen of the optic disc. Conclusions. Thus, the use of OCT for the diagnosis of optic neuropathies in the acute period showed that under conditions of inflammatory lesions is more characteristic of edema and an increase in the thickness of the layer of nerve fibres. In ischemic neuropathy, on the contrary, a decrease in the thickness of nerve fibres is more characteristic, which correlates in location with the localization of scotoma in the field of view. Therefore, the use of OCT of the optic nerve will help in understanding the pathogenesis of forms of optic neuropathy. This will help in the choice of treatment tactics