RESUMO
BACKGROUND: There is insufficient data on the clinical and radiological features of neuromyelitis optica (NMO) and neuromyelitis optica spectrum disorders (NMOSD) from India. OBJECTIVE: The objective of the following study is to examine the clinico-radiological features of NMO and NMOSD in an Indian cohort. MATERIALS AND METHODS: This retrospective study included 44 consecutive patients who (1) satisfied the 2006 Wingerchuk criteria for NMO (16 seropositive and 7 seronegative); or (2) had isolated or recurrent optic neuritis (ON) with seropositivity (n = 4); or (3) had isolated or recurrent myelitis with seropositivity (n = 17). RESULTS: The female:male ratio was 7.8:1 with median age of onset 26.5 (range 8-72). Annualized relapse rate (ARR) was comparable across all groups (F [3, 40] = 0.938 and P = 0.431). Various presentations other than ON and myelitis were noted. All 40 patients with myelitis had spinal cord lesions involving ≥3 vertebral segments during the course of the disease. Cervicomedullary involvement was seen in 32.5% (13/40) patients. Brain magnetic resonance imaging was available for 40 patients; eight of these (20%) had brain lesions in locations described in multiple sclerosis (MS), 27.5% (11/40) had lesions at sites unusual for MS and 52.5% (21/40) had normal brain imaging. CONCLUSION: NMO and NMOSD patients in this cohort have comparable ARR regardless of clinical presentation, supporting the emerging trend of treating all patients with immunotherapeutic agents at an early stage. Varied presentations seen in NMO and NMOSD highlight the need for a high index of suspicion for NMO in demyelinating episodes not classical for MS.
RESUMO
BACKGROUND: Neuromyelitis optica (NMO) is an immune-mediated inflammatory demyelinating disorder of the central nervous system with a predilection for the optic nerves and the spinal cord. Immunopathological evidence suggests that the target antigen of the disease is aquaporin-4. An IgG antibody against this protein has been explored as a molecular marker for the disease and as a diagnostic tool due to its high sensitivity and specificity in various populations. OBJECTIVE: To assess the value of NMO-IgG testing in Indian patients with clinical and magnetic resonance imaging features consistent with NMO and longitudinally extensive transverse myelitis (LETM). MATERIALS AND METHODS: Forty-five patients with clinical and magnetic resonance imaging features consistent with NMO, LETM, and MS were tested for serum NMO-IgG. Of these patients, 22 patients satisfied revised (2006) Wingerchuk criteria for NMO (excluding NMO-IgG status) and 11 patients had LETM. Twelve patients satisfied the revised (2010) McDonald criteria for multiple sclerosis (MS). RESULTS: Of the 21 patients, satisfying the criteria for NMO and for whom the test results were available, 17 were positive for NMO-IgG (80.9%), and of the 11 patients having LETM, 6 (54.5%) were positive for NMO-IgG. In one patient with NMO, the test result was not available. None of the 12 patients satisfying McDonald criteria for MS showed NMO-IgG seropositivity. CONCLUSION: Our study suggests that it is worthwhile to pursue NMO-IgG testing as a diagnostic tool for patients with clinical and Magnetic Resonance Imaging (MRI) features consistent with NMO and LETM in the Indian population.
RESUMO
Tubulobulbar complexes (TBCs) are actin-based structures that help establish close contact between Sertoli-Sertoli cells or Sertoli-mature germ cells (spermatids) in the seminiferous tubules of the testes. They are actin-rich push-through devices that eliminate excess spermatid cytoplasm and prepare mature spermatids for release into the tubular lumen. Just prior to spermiation, the elongated spermatid interacts with the Sertoli cell via an extensive structure comprising various adhesion molecules called the apical ectoplasmic specialization which is partially replaced by the apical TBC, on the concave surface of the spermatid head. The sperm release process involves extensive restructuring, namely the disassembly and reassembly of junctions at the Sertoli-spermatid interface in the seminiferous epithelium. Based on the presence of different classes of molecules in the TBCs or the defects observed in the absence of TBCs, the main functions attributed to TBCs are elimination of excess spermatid cytoplasm, endocytosis and recycling of junctional molecules, shaping of the spermatid acrosome, and forming transient anchoring devices for mature spermatids before they are released. This review summarizes the recent findings that focus on the role of TBCs in cell cytoskeleton restructuring during sperm release in the testes and the molecular mechanism involved.
