Basal Nerves Research Articles

All Cuban Calycolpus are really Eugenia (Myrtaceae)

A taxonomically controversial group of Cuban Myrtaceae is that of the species of Calycolpus Berg (1855-1856: 378) as defined by Johannes Bisse (Flickinger et al. 2020). Initially, Bisse (1983) transferred to Calycolpus five species from eastern Cuba, which share axillary, umbelliform inflorescences, 4-6-seeded fruits with soft coverings, and a type of venation observed in the type species of Calycolpus, in which the basal lateral nerves are recurved. Of these species, four were described in Eugenia Linnaeus (1753: 470) [E. cristalensis Urban, E. excisa Urban, E. lucens Alain and E. nipensis Urban] and one in Psidium Linnaeus (1753: 470) [P. reversum Urb.]. With such combinations to Calycolpus, Bisse (1983) elimnated from the extensive listing of Eugenia from the flora of Cuba the species containing more than one seed in each fruit, while considering that he cleared the diffuse concept of this genus as it had been approached by Alain (1953a).

<I>Miconia nordestina</I> (Melastomataceae), A New Species from Brazil

Abstract Miconia nordestina has been collected 80 times in four Brazilian states (Ceara , Pernambuco, Alagoas, and Bahia) since 1939, but remained undescribed. It shares its glabrescent leaves, lax inflorescences, and small flowers with white stamens with several species of Miconia that are difficult to distinguish from one another. It can be recognized by the decorticant branches covered with sessile-stellate trichomes, opposite leaves with basal nerves, entire margins, and glabrous or glabrescent abaxial surface, panicles without additional lateral branches and without accessory branches at the nodes, 5-merous flowers with regular, well-defined calyx lobes, the calyx tube glabrous inside, rounded to emarginate petals, weakly dimorphic stamens with appendaged connectives, and large and ventral inclined anther pores that are equal to or broader than the anther thecae, glabrous ovary and style. It always occurs in montane habitats between 250 and 1,100 m where it usually grows in riparian forests associate...

Superficial cerebral siderosis as stroke-mimic

Superficial siderosis of the central nervous system results from hemosiderin deposition in the subpial layers of the brain and spinal cord [1]. A clinical history of subarachnoid hemorrhage is often absent, and in most cases patients present with slowly progressive gait ataxia and sensorineural hearing impairment [1]. We describe a patient diagnosed with superficial cortical siderosis presenting with sudden occurrence of aphasia and facial palsy mimicking a cerebrovascular event. A 87-year-old man presented with expressive aphasia and hemisensory loss involving right hand and face. No headache was reported. His previous medical history was notable for high blood pressure treated with valsartan 80 mg/day. Neurological examination revealed a mild expressive aphasia with right central facial palsy. A CT head without contrast showed a rim of cortical hyperdensity on the left-side central sulcus (Fig. 1a). T2weighted and gradient-echo magnetic resonance imaging (MRI) showed a T2 hypointensity along the cortical sulci of both sides, indicative of hemosiderin deposition (Fig. 1b). Diffusion-weighted MRI, performed when neurological deficits were still present, showed no sign of recent ischemia and MR-angiography did not show evidence of a vascular malformation or aneurysm. Spin-echo and gradient-echo sequences failed to reveal any source for bleeding such as amyloid angiopathy or cavernomas, and no evidence of hemosiderin deposition in posterior fossa was found. Since the presence of aphasia pointed to a cortical disturbance, a CSF examination was not performed; however, a cervical spine MR with contrast did not show any vascular abnormality. Laboratory examinations, duplex ultrasound imaging and EEG revealed no abnormalities. Within 2 days the aphasia and facial palsy recovered. A diagnosis of superficial cerebral siderosis was made and the patient discharged. Superficial siderosis of the central nervous system is characterized by hemosiderin deposition in those parts of the central nervous system adjacent to cerebrospinal fluid, with following discoloration of the leptomeninges and adjacent parenchyma. The most involved sites are the superior vermis, cerebellar folia, basal frontal lobe, temporal cortex, brainstem, spinal cord, and cranial nerves I and VIII [1]. The clinical features are related to the site of hemosiderin deposition, and in most cases patients present with slowly progressive cerebellar ataxia (often with dysarthria), often associated with hearing loss (sometimes with vestibular failure), which may be accompanied by tinnitus [2]. However, also pyramidal and sensory signs are common and may relate to brainstem or spinal cord involvement. Sensory symptoms or a sensory level are rarely present [1]. Hemosiderin deposition around the brain, brainstem and spinal cord results in the characteristic hypointensity seen on T2-weighted MRI. Gradient-echo T2-weighted images F. Brigo (&) Section of Clinical Neurology, Department of Neurological, Neuropsychological, Morphological and Movement Sciences, University of Verona, Piazzale L.A. Scuro 10, 37134 Verona, Italy e-mail: dr.francescobrigo@gmail.com

Laser Scanning In Vivo Confocal Microscopy Demonstrating Significant Alteration of Human Corneal Nerves Following Herpes Zoster Ophthalmicus

60-YEAR-OLD WOMAN with herpes zoster ophthalmicus(HZO) of the right eye was treated with 800 mg ofacyclovir5timesperdayfor7days. Therewasnosignificantmedicalhis- tory. She developed reduced vision and ocular pain due to HZO disci- form keratouveitis (a central disc- like region of corneal edema with objective of the microscope was placedincontactwiththecorneaand thepatientwasaskedtofixateondis- tance targets arranged in a grid pat- tern to enable acquisition of mul- tipleconfocalimagesoverawidearea of cornea. Macromedia Freehand 10 (SanFrancisco,California)wasused to arrange images into wide-field montages of the subbasal nerve plexus. A montage of the left sub- basal nerve plexus demonstrated nerve fiber bundles arranged in a ra- diatingpattern,convergingtoforma typical clockwise whorl, or vortex, pattern,andLangerhans(antigenpre- senting) cells were distributed throughout the imaged region (Figure 1). In contrast, a montage of the right subbasal nerve plexus could not be produced owing to the scarcity of subbasal nerves. Indeed, only occasional nonbranching sub- basal nerves were visible in the mid- peripheral cornea (Figure 2A) and most images of the right cornea con- sisted of a bare, nerve-free Bowman layer (Figure 2B) with Langerhans cells (Figure 2C). COMMENT

Immunohistochemical Investigation of the Nitrergic System in the Taste Organ of the Frog, Rana esculenta

We have studied by immunocytochemistry, the taste discs of the frog, Rana esculenta, with the aim of providing morphological and neurochemical data on the nitrergic system and of assessing the eventual presence of intrinsic neurons associated with the gustatory organs. In taste discs, antibodies against neuronal nitric oxide synthase (nNOS) revealed a positive immunoreaction in the taste receptor cell bodies and processes. The basal cells were also stained. All the fungiform papillae contained intragemmal nerve fibers showing nNOS immunoreactivity; these fiber were mainly located in the basal plexus. Immunoreactive nerve fibers were also visible at the periphery of the papilla-contacting ciliate cells, which form a ring around the taste disc. In conclusion, the findings obtained in this study suggest that the occurrence of nNOS-immunoreactivity in basal cells, taste cells and nerves might reflect a role for nitric oxide in taste mechanisms of Amphibia. The results may also sustain the physiological implication of NO as a molecule involved in the local target function of maintaining the taste bud mucosal integrity and in regulating the blood flow to the epithelium.

Speech Science: An Integrated Approach to Theory and Clinical Practice

Speech Science: An Integrated Approach to Theory and Clinical Practice

In vivo confocal microscopy of fleck dystrophy.

To use in vivo confocal microscopy to evaluate corneas with fleck dystrophy. Both eyes of three patients with corneal fleck dystrophy were examined with a scanning slit confocal microscope. Corneal epithelium, stroma, and endothelium were evaluated, as well as the basal epithelial and stromal nerves. The epithelium did not show any anomalies, but the basal nerves showed hyperreflective inclusions. Throughout the entire stroma, hyperreflective dots of various shapes were seen. These consisted mostly of spherical matter with a diameter of 3-5 microm and were sometimes enclosed in cyst-like structures. The majority of the stromal cells and stromal nerves appeared normal. The endothelial cell layer was unaffected. In vivo confocal microscopy demonstrates previously unreported inclusions in the basal nerves of fleck dystrophy corneas. In addition to this new finding, the study confirms earlier histopathologic reports, demonstrating accumulation of pathologic material in the stromal cells.

In vivo confocal microscopy after photorefractive keratectomy in humans. A prospective, long-term study.

To assess corneal morphological characteristics in vivo after photorefractive keratectomy (PRK) in humans. Eighteen eyes were examined before and after PRK by means of in vivo confocal microscopy. Epithelial, stromal, and endothelial morphological characteristics were recorded. Minimum follow-up was 12 months. Immediately after PRK, the anterior stroma showed marked intercellular edema. At 1 month, fine linear structures were noted in the anterior stroma and midstroma, and a thin hyperreflective scar was present. The linear structures and the scar tissue were more marked at 4 months but were still present up to 26 months. Anterior stromal keratocyte density increased significantly 1 and 4 months after PRK, whereas midstromal and posterior keratocytes and endothelial cell densities did not change. Basal epithelial nerves were recognizable as early as 1 month after PRK. Contact lens-related microdots in the stroma remained unaffected. The stromal linear structures represent a finding that is detectable only by confocal microscopy at high magnification, is not related to previous contact lens wear, and is still visible 26 months after PRK. The extension of these structures as far as the midstroma indicates that the permanent corneal changes caused by PRK affect deeper stromal layers than the immediate subepithelial region.

Effects of dichlobenil on ultrastructural morphology and cell replication in the mouse olfactory mucosa.

The herbicide dichlobenil (2,6-dichlorobenzonitrile) is a tissue-specific inducing necrosis in the olfactory mucosa. Transmission electron microscopy showed vacuolations (1 hr) and necrosis (4 hr) in the Bowman's glands following intraperitoneal injection of dichlobenil (25 mg/kg) in C57B1 mice, whereas no lesions were noted in the olfactory neuroepithelium at these timepoints. Twenty-four hr following injection (25 mg/kg), most of the propria and the olfactory epithelium were severely damaged; the basal lamina, nerves, and blood vessels in the lamina propria, however, remained intact. Following a lower dose (12 mg/kg), the lesions were not as pronounced. The effects of dichlobenil (6, 12, and 25 mg/kg) on cell replication in the olfactory mucosa, as determined by incorporation of 3H-thymidine 3 days later, were more pronounced in the lamina propria than in the neuroepithelium and occurred at a lower dose in the lamina propria than in the neuroepithelium. Together these studies support the previous proposal that dichlobenil induces a primary damage in the Bowman's glands.

Technical Aspects of Intraoperative Monitoring of Lower Cranial Nerve Function

The efficacy of monitoring facial nerve activity in decreasing long-term morbidity has promoted an interest in monitoring other at-risk cranial nerves during procedures that involve manipulation of the basal cranial nerves. This presentation details practical techniques for monitoring the lower cranial nerves, which have been experientially developed over the past 9 years. Emphasis is placed on the selection of electrodes and procedural changes required for reliable and safe stimulation of the basal cranial nerves. Either paired hook-wire or tethered needle electrodes can be used for monitoring glossopharyageal, accessory, and hypoglossal nerve function. Several options for monitoring vagus nerve function are discussed. Of these, the transoral placement of paired hook-wire electrodes remains the most reliable, cost-effective, and least morbid technique. Electrical stimulation of the glossopharyngeal and vagus nerves carries the risk of unanticipated, potentially irreversible disturbances in cardiovascular function. Guidelines for type and optimal placement of stimulating electrodes and recommended intensity levels to prevent unfavorable reactions are presented.

Scanning Slit Confocal Microscopic Observation of Cell Morphology and Movement within the Normal Human Anterior Cornea

Noninvasive in vivo observations of the anterior human cornea were performed to study cell structure and dynamics. Cellular elements were identified by their location, morphology, and pattern of movement. The hypothesis that cells in the epithelial layer of the normal cornea migrate centripetally was tested. Using a scanning slit confocal microscope with a new 0.75-numeric aperture contact objective, individual cells of normal human corneas were observed over time, quantifying the velocity and direction of cellular movement within the basal epithelial layer. Basal epithelial cells, wing cells, the basal epithelial nerve plexus, and the subepithelial nerve plexus were identified readily. Centripetal motion was observed for three corneal cell types: basal epithelial cells, basal epithelial nerves, and unidentified cellular elements (possibly Langerhans cells). The unidentified cellular elements moved along the length of the basal epithelial nerves. The basal epithelial nerve plexus maintained a roughly stable topology as it slid centripetally. New nerve material appeared at the site of entry of the nerve into the epithelium. No growth cones were present at the distal termini of the growing epithelial nerves. In the midperiphery of the normal human cornea, basal epithelial cells and nerves slide centripetally, probably in concert. Unidentified cellular elements used the basal epithelial nerve plexus as a pathway for intraepithelial movement. Observations in this study suggest that neurite growth occurred by the addition of new membrane material along the length of the axon rather than at a distal growth cone.

Aneurysm of the intracranial carotid artery; syndrome of frontal headache with oculomotor nerve paralysis.

It is proposed to critically analyze 31 consecutive cases of aneurysm of the intracranial carotid artery, the chief features of which were oculomotor paralysis or paresis associated with frontal or orbital head pains, and to show that these combined symptoms are sufficient to permit a presumptive diagnosis of aneurysm of the intracranial carotid artery. Of the 31 cases with this clinical diagnosis, based primarily on these two symptoms, all were proved either by arteriography or operative exposure and many of them by both. Surgical therapy and operative results in 26 of the patients will be discussed. This closely related combination of symptoms has been recognized and discussed by many observers, particularly in relation to underlying pathologic states that might give rise to them. Thus aneurysms of the intracranial carotid, as well as the relationship of anomalous vessel arrangements to the basal cranial nerves, have been thoroughly studied. A close analysis