Postnatal development of parvalbumin and calbindin D28K immunoreactivities in the cerebral cortex of the rat

Parvalbumin and calbindin D28k immunoreactivities were examined in the neocortex of the rat during postnatal development. Parvalbumin-immunoreactive nonpyramidal neurons first appear in layer V and later in layers VI and IV, and then in II and III. Immunoreactive terminals forming baskets surrounding unlabelled somata appear about 2 days later. The first parvalbumin-immunoreactive neurons appear in the retrosplenial and cingulate cortices, and the rostral region of the primary somatosensory cortex at postnatal days 8 or 9 (P8–P9). These regions are followed by the primary visual, primary auditory and motor cortices at P11. Parvalbumin immunoreactivity appears last in the secondary areas of the sensory regions and association cortices. Adult patterns are reached at the end of the 3rd week. Calbindin D28K-immunoreactive nonpyramidal neurons are found at birth in all cortical layers excepting the molecular layer. The intensity of the immunoreaction increases during the first 8 or 11 days of postnatal life, first in the inner and later in the upper cortical layers, following, therefore, an inside-out gradient. Heavily-labelled calbindin D28K-immunoreactive nonpyramidal cells dramatically decrease in number from P11 to P15 due mainly to a decrease of the multipolar subtypes. This suggests that two populations of calbindin D28k-immunoreactive nonpyramidal neurons are produced in the neocortex during postnatal development: one population of neurons transitorily expresses calbindin D28k immunoreactivity; the other population is composed of neurons that are permanently calbindin D28k immunoreactive. In addition to heavily labelled nonpyramidal cells, a band of weakly labelled pyramid-like neurons progressively appears in layers II and III throughout the cerebral cortex, beginning in layer IV in the somatosensory cortex by the end of the 2st week. Adult patterns are reached at the end of the 3rd week. These results indicate that parvalbumin and calbindin D28k immunoreactivities in the cerebral neocortx follow different characteristic patterns during postnatal development. The appearance of parvalbumin immunoreactivity correlates with the appearance of the related functional activity in the different cortical regions, and, probably, with the appearance of inhibitory activity in the neocortex. On the other hand, the early appearance of calbindin D28k immunoreactivity in the neocortex may be related to the early appearance of calbindin immunoreactivity in many other brain regions, and suggests another, as yet unknown, role for this calcium-binding protein during development of the cerebral cortex.     

大鼠小脑和下橄揽核中含Calbindin－D28KmRNA的神经元的生后发育

本实验应用原位杂交组织化学方法观察了大鼠小脑皮质和下橄榄核中含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ＫｍＲＮＡ的神经元的生后发育过程。发现在刚出生时，小脑浦肯野氏细胞已含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ＫｍＲＮＡ，其表达水平在生后第３周时达高峰并持续至成年期。但在下橄榄核中，含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ＫｍＲＮＡ的神经元在生后第７天时才出现，其数量及标记强度在生后第３、４周时迅速增加，并达成年水平。结合以往的资料分析，在小脑中，Ｃａｌｂｉｎｄｉｎ－Ｄ２８Ｋ可能与浦肯野氏细胞的成熟（突起的形成及伸长、突触的形成）过程有关。而在下橄榄核中，Ｃａｌｂｉｎｄｉｎ－Ｄ２８Ｋ主要参与成年期神经元的正常生理功能。     

Calbindin D28k‐like immunoreactivity during the formation of the enamel‐free area in the rat molar teeth

Previous studies have demonstrated the presence of calbindin D28k in the ameloblasts derived from the inner enamel epithelium. The occlusal surfaces of the rodent molars partly lack the enamel covering, which is referred to as enamel‐free area (EFA). In the present study, we compared the immunohistochemical localization of calbindin D28k‐like immunoreactivity (CB‐LI) in the cells at the EFA (EFA cells) and ameloblasts of the rat molar teeth at the light microscopic level. CB‐LI was strong in the ameloblasts of the presecretory through the protective stages, while it was faint at the late secretory to transitional stages. However, some mature ameloblasts lacked the immunoreactivity. On the other hand, the majority of EFA cells showed distinct polarization and elongation that were absent in few cells at the early stage of EFA formation. At all stages, the EFA cells adjacent to the ameloblasts showed CB‐LI, however, some cells adjacent to the mature ameloblasts lacked the reaction. Intensive CB‐LI was demonstrated in EFA cells at the reduced enamel epithelium. These immunohistochemical findings suggest EFA cells have cytochemical properties similar to those of ameloblasts. Anat Rec 258:384–390, 2000. © 2000 Wiley‐Liss, Inc.     

Calbindin D28K and parvalbumin gene expression in rat embryonic ventral forebrain grafts

The present study characterizes expression of calbindin D28 K (CB-D28 K) and parvalbumin (PV) in ventral forebrain (VFB) grafts placed in the neocortex of adult rats bearing quisqualic acid lesions to the nucleus basalis magnocellularis. Three to nine months after transplantation surgery, rats were killed for in situ hybridization with probes to CB-D28K or PV and for immunohistochemistry with antibodies to CB-D28K or PV. In addition, an antibody to choline acetyltransferase (ChAT) was used to characterize the cholinergic component in the graft and an antibody to tyrosine hydroxylase (TH) to explore catecholaminergic innervation of the graft. Quantitative analysis of CB-D28K and PV messenger ribonucleic acid (mRNA) was based on counts of silver grains generated by emulsion autoradiography. Cells expressing CB-D28K mRNA were significantly larger than such cells in the adult VFB and the mean number of silver grains per cell was significantly greater than to such cells in the adult VFB. The level of CB-D28K mRNA expression as calculated by ratio of silver grains per unit area was also significantly increased. Quantification of PV mRNA showed no significant differences between the cells in the graft and in the adult VFB. In order to begin to interpret these findings, a comparison was made with such cells in the VFB of developing rats. Brain sections were sampled from embryonic day 17 and postnatal days 1, 5, 12, 19 and adult (6–12 months of age). Cells expressing CB-D28K mRNA were detected in ventral forebrain from postnatal day 5 and cells expressing PV mRNA were detected in ventral forebrain from postnatal day 19. In the course of normal development of the ventral forebrain, no CB-D28K cells were found that were as large or expressed such high levels of CB-D28K mRNA as observed in the grafts. We conclude that changes in grafted cells expressing CB-D28K do not reflect an arrest of developmental processes. TH immunohistochemistry revealed lack of catecholaminergic innervation of the graft, whereas adult mediolateral septal cells that express CB-D28K receive such innervation in addition to other neurotransmitter inputs. Imbalance in neurotransmitter inputs to grafted cells expressing CB-D28K is discussed as a possible factor in their increased size and gene expression. Received: 4 June 1996 / Accepted: 11 June 1997     

大鼠孤束核内含calbindin D-28K的内脏伤害性神经元向终纹床核的投射—荧光金标记结合免疫荧光技术研究

既往的研究证明孤束核和终纹床核参与内脏伤害性信息的传递和调控。Calbindin D-2 8K是钙结合蛋白家族的成员 ,为神经细胞特别是投射神经元的选择性标记物。应用荧光金逆行追踪和免疫荧光技术相结合的方法 ,对给予内脏伤害性刺激后大鼠孤束核内 FOS的表达并显示 Calbindin D-2 8K免疫阳性的神经元向终纹床核的投射进行了研究。结果显示 :将荧光金注入一侧终纹床核外侧部后 ,孤束核中尾段内双侧出现荧光金逆行标记细胞 ,注射区同侧占优势 :孤束核的相同平面可观察到双侧等量分布的免疫反应阳性的 Calbindin D-2 8K和 FOS细胞 :三种阳性细胞的分布有明显的重叠现象。在其重叠分布区可见荧光金 /Calbindin D-2 8K、FOS/Calbindin D-2 8K、荧光金 /FOS双重阳性以及荧光金 /Calbindin D-2 8K/FOS三重阳性细胞。除 FOS/Cal-bindin D-2 8K双重阳性细胞为双侧分布外 ,荧光金 /Calbindin D-2 8K、荧光金 /FOS双重阳性以及荧光金 /Calbindin D-2 8K/F OS三重阳性细胞的出现均以注射区同侧为主。荧光金 /Calbindin D-2 8K、F OS/Calbindin D-2 8K双重阳性和荧光金 /Calbindin D-2 8K/F OS三重阳性神经元占孤束核内 Calbindin D-2 8K免疫阳性神经元总数的百分比分别为 2 .79%、15 .3 %和 2 .5 6% ;荧光金/Calbindin     

Immunohistochemical localization of calbindin D28-k,parvalbumin, and calretinin in the cerebellar cortex of the circling mouse

The spontaneous mutant circling mouse has an autosomal recessive pattern of inheritance and is an animal model for deafness, which is characterized by circling, head tossing, and hyperactivity. Since the main pathology in circling mice lies in the organ of Corti, most studies on deaf mice have focused on auditory brain stem nuclei. No studies regarding behavior-related CNS changes in circling mice have been reported. The major center of sensory input for modulation of motor activity is best-studied in the cerebellum. Considering the importance of calcium homeostasis in numerous processes, calcium-binding proteins (CaBPs), such as calbindin D-28k (CB), parvalbumin (PV), and calretinin (CR), may play crucial roles in preserving cerebellar coordinated motor function. Thus, the distribution of CB, PV, and CR was determined in the cerebellum using immunohistochemical methods to compare immunoreactivity (IR) of CaBPs between wild-type (+/+), heterozygous (+/cir), and homozygous (cir/cir) mice. The IR of CB and PV was predominantly observed in the Purkinje cell layer of all three genotypes. Compared with the +/+ genotype, the relative mean density of CB and PV IR in the Purkinje cell layer and CR IR in the granular layer was significantly decreased in the cir/cir genotype. Changes in calcium homeostasis in parallel fiber/Purkinje cell synapses could diminish cerebellar control of motor coordination. A number of deficiencies among the CaBPs lead to distinct alterations in brain physiology, which may affect normal behavior.     

含Parvalbum in和Calbind in D-28k样免疫阳性神经元在大鼠三叉神经本体觉中枢通路的分布

本研究应用免疫组织化学技术对Ｐａｒｖａｌｂｕｍ ｉｎ（ＰＶ）和Ｃａｌｂｉｎｄｉｎ Ｄ ２８ｋ（ＣＢ）样免疫阳性神经元在大鼠三叉神经本体觉中枢通路上的分布状况作了普查。结果表明： 这两种钙结合蛋白在该通路上具有下列的分布特点：（１）三叉神经中脑核神经元几乎全部为ＰＶ 样免疫阳性,胞体和突起染色强或中等强度,胞体大（１８～３０ μｍ ）,多为假单级神经元,偶见中等大小的多极神经元。（２）在三叉神经脊束核吻侧亚核尾侧段水平的三叉神经脊束核吻侧亚核背内侧部及邻接的网状结构中可看到由ＰＶ 样免疫阳性神经元构成的两团深染区,外侧者大,内侧者小,胞体呈圆形、三角形或不规则形（９～１６ μｍ ）;在此处ＣＢ样免疫阳性细胞亦呈类似分布。（３）“带状区”内ＰＶ 样免疫阳性细胞多为具有短突的多极神经元;在三叉上核尾外侧部,ＰＶ 样神经元分布稀疏,但在感觉主核背内侧部则呈高密度分布;ＡＶＭ 、ＡＤＯ 等两个位于“带状区”腹侧部的新发现的小核团亦可观察到阳性细胞和突起。此“带状区”内ＣＢ样免疫阳性细胞数目较少,分布也稀疏,但胞体较大（１１～１８ μｍ ）,呈三角形、圆形或不规则形,轴突上可见少量的串珠状膨体。在ＡＤＯ 中ＣＢ样免疫阳性细胞的分布较Ｐ?     

Mapping to distal Xq28 of nonspecific X‐linked mental retardation MRX72: Linkage analysis and clinical findings in a three‐generation Sardinian family

Families with mentally retarded males found to be negative for FRAXA and FRAXE mutations are useful in understanding the genetic basis of X‐linked mental retardation. According to the most recent data (updated to 1999), 69 MRX loci have been mapped and 6 genes cloned. Here we report on a linkage study performed on 20 subjects from a 4‐generation Sardinian family segregating a non‐specific X‐linked recessive mental retardation (XLMR)(MRX72) associated with global delay of all psychomotor development. Five of 8 affected males have been tested for mental age, verbal and performance skills and behavioral anomalies; mental impairment ranged from mild to severe. Only minor anomalies were present in the affected subjects. Two‐point linkage analysis based on 28 informative microsatellites spanning the whole X chromosome demonstrated linkage between the disorder and markers DXS1073 and F8c in Xq28 (maximum Lod score of 2.71 at θ = 0.00). Multipoint linkage analysis confirmed the linkage with a Z_max of 3.0 at θ = 0.00 at DXS1073 and F8c. Recombination in an affected male at DXS1073 and F8c allowed us to delimit centromerically and telomerically the region containing the putative candidate gene. The region, where MRX72 maps, overlaps that of another MRX families previously mapped to Xq28, two of which harbored mutations in GDI. Involvement of this gene was excluded in our family, suggesting another MRX might reside in Xq28. Am. J. Med. Genet. 94:376–382, 2000. © 2000 Wiley‐Liss, Inc.     

VEGF‐C,VEGF‐D and VEGFR‐3 expression in peripheral neuroblastic tumours

Ramani P, Nash R, Radevsky L, Patel A, Luckett M & Rogers C
(2012) Histopathology
VEGF‐C, VEGF‐D and VEGFR‐3 expression in peripheral neuroblastic tumours Aims: More than 50% of neuroblastomas (NBs) present with haematogenous and/or lymphatic metastasis; however, little is known about the clinicopathological significance in NBs of the key lymphangiogenesis growth factors vascular endothelial growth factor (VEGF)‐C and VEGF‐D and the receptor VEGFR‐3. Methods and results: Ninety‐three NBs and nine ganglioneuromas (GNs) were immunostained for VEGF‐C, VEGF‐D and VEGFR‐3. VEGF‐C and VEGF‐D were present in 76% and 82% of the NBs, respectively. There was no significant difference in VEGF‐C expression between NBs and GNs. VEGF‐D expression was significantly higher in NBs compared with GNs and in MYCN‐amplified NBs. VEGFR‐3 tumoral cell expression (VEGFR‐3c), present in 48% of the NBs, was significantly higher in NBs from children ≥18 months at presentation and those belonging to a high‐risk group. VEGFR‐3 lymphovascular density was increased significantly in NBs compared with GNs and in NBs associated with adverse clinicopathological and biological factors. Lymphovascular invasion, assessed in VEGFR‐3‐stained vessels, was present in ～50% of NBs. Cox regression analyses demonstrated that VEGFR‐3c expression was associated with a significantly shorter event‐free survival and that its effect was independent of the important pathological variable, mitosis–karyorrhexis index. Conclusions: VEGF‐D and VEGFR‐3 up‐regulation support tumour progression in NB and VEGFR‐3c may provide a useful prognostic marker in NBs.     

Evidence for the involvement of calbindin D28k in the presenilin 1 model of Alzheimer's disease

Pathological hallmarks of Alzheimer's disease include memory deficits, accumulation of amyloid beta (Aβ) plaques, the appearance of neurofibrillary tangles, and dysregulation of calcium homeostasis, which has been linked to mutations in the presenilin gene that code for presenilin (PS) proteins. PSs are a family of multi-pass transmembrane proteins where normal presenilins (PS1 and PS2) are highly localized in the endoplasmic reticulum (ER). Several past studies have explored alterations in long-term potentiation (LTP), a proposed molecular correlate of memory, and in behavioral tests of spatial memory in a variety of PS1 models. These reports suggest that calcium plays a role in these alterations, but mechanistic explanations for changes in LTP and in behavioral tests of memory are still lacking. To test the hypothesis that calcium-related mechanisms, such as changes in calcium buffering, are associated with alterations in LTP and memory, we utilized in vitro experimental paradigms of LTP in hippocampal slices obtained from the PS1-M146V transgenic mouse model of Alzheimer's disease (AD). We also used the in vivo Morris water maze (MWM), a test for hippocampal dependent spatial memory. In addition, we used cellular assays to explore molecular mechanisms. We confirm that PS1 mutations (M146V) enhance LTP. We also find increases in some parameters of the MWM, and alterations in other parameters, such as path length indicating impairment in cognitive functioning in PS1-M146V mice. In addition, these findings are observed in association with increased calbindin D28K expression in the CA1 hippocampus of PS1-M146V mice.     

Immunocytochemical Localization of Calbindin D28K,Calretinin, and Parvalbumin in Bat Superior Colliculus

The purpose of this study was to investigate the localization of cells containing the calcium-binding proteins (CBPs) calbindin D28K (CB), calretinin (CR), and parvalbumin (PV) in the superior colliculus (SC) of the bat using immunocytochemistry. CB-immunoreactive (IR) cells formed a laminar tier within the upper superficial gray layer (SGL), while CR-IR cells were widely distributed within the optic layer (OL). Scattered CR-IR cells were also found within the intermediate gray, white, and deep gray layers. By contrast, PV-IR cells formed a laminar tier within the lower SGL and upper OL. Scattered PV-IR cells were also found throughout the intermediate layers, but without a specific laminar pattern. The CBP-IR cells varied in size and morphology: While most of the CB-IR cells in the superficial layers were small round or oval cells, most CR-IR cells in the intermediate and deep layers were large stellate cells. By contrast, PV-IR cells were small to large in size and included round or oval, stellate, vertical fusiform, and horizontal cells. The average diameters of the CB-, CR-, and PV-IR cells were 11.59, 17.17, and 12.60 μm, respectively. Double-immunofluorescence revealed that the percentage of co-localization with GABA-IR cells was 0.0, 0.0, and 10.27% of CB-, CR-, and PV-IR cells, respectively. These results indicate that CBP distribution patterns in the bat SC are unique compared with other mammalian SCs, which suggest functional diversity of these proteins in visually guided behaviors.     

Interleukin‐ 28B: a prognostic marker in interferon based therapy of chronic HCV patients of the Pakistan with variable treatment response

Unfortunately Pakistan carries one of the world's highest burdens of chronic hepatitis along with mortality due to liver failure and hepatocellular carcinoma. Scientists after extensive research have come up with this outcome that host genetics play a vital role in dictating the type of treatment response produced by the patients. In 2009, a genome wide association study (GWAS) revealed that genetic variants in close proximity to the IL28B (IFNL3) gene predicted greater likelihood of achieving sustained virological response (SVR) following treatment with pegylated IFN‐alpha (peg INF‐α) and ribavirin. IL28B (rs12979860 and rs8099917) single nucleotide polymorphisms (SNPs) have been recently found among the Pakistani population associated with response to chronic HCV infection INF‐α + ribavirin therapy. Therefore, this study was aimed to investigate the IL‐28B protein levels in the HCV infected patients. The findings showed that the serum IL28B protein level was higher in HCV infected patients as compared to healthy controls (7.743 ± 1.519 pg/mL versus 1.600 ± 0.06054 [mean ± SEM], p < 0.05). When the chronic hepatitis C (CHC) patients were further categorized into SVR and NR (non‐responders) on the basis of treatment outcomes, the mean IL28B protein level was higher in NRs (15.54 ± 3.609) than SVRs (4.259 ± 0.3405). Thus, there was a significant correlation between IL28B protein level in varied treatment response (p < 0.05). However, the findings can lead us to propose that IL28B could be used as a prognostic marker. It can help the clinicians to take better pre‐informed decisions whether to take combinational therapy of peg IFN ± ribavirin or not. This will in turn prove beneficial for the patient by saving patients’ health, treatment cost and undesirable treatment side effects.     

Fine‐needle aspiration cytology diagnosis of non‐Hodgkins lymphoma in a resource‐challenged environment

To establish the role of fine‐needle aspiration cytology (FNAC) as a diagnostic tool for non‐Hodgkins lymphoma in a resource challenged environment. This study was conducted on patients with lymphadenopathy, attending various clinics over a period of 18 months. FNAC of the enlarged lymph nodes was performed and biopsy, special stains and immunohistochemical staining was done in selected cases. Out of the total 275 cases, 42 cases (16%) were primary lymphoproliferative disorders. Non‐Hodgkin lymphoma comprised of 32 cases (76.2% of all lymphomas), Hodgkin lymphoma‐10 cases and the rest were metastatic carcinoma. The diagnostic accuracy for non‐Hodgkin Lymphoma was 93.3%, sensitivity 95.4%, and specificity 87.5%. FNAC is a rapid, safe, easy, and nonexpensive diagnostic technique which can be used for early diagnosis of non‐Hodgkins lymphoma. Diagn. Cytopathol. 2011. © 2010 Wiley‐Liss, Inc.     

Prenatal acoustic stimulation influences neuronal size and the expression of calcium-binding proteins (calbindin D-28K and parvalbumin) in chick hippocampus

Prenatal auditory enrichment by species-specific sounds and sitar music enhances the expression of immediate early genes, synaptic proteins and calcium binding proteins (CaBPs) as well as modifies the structural components of the brainstem auditory nuclei and auditory imprinting area in chicks. There is also facilitation of postnatal auditory preference of the chicks to maternal calls following both types of sound stimulation indicating prenatal perceptual learning. To examine whether the sound enrichment protocol also affects the areas related to learning and memory, we assessed morphological changes in the hippocampus at post-hatch day 1 of control and prenatally sound-stimulated chicks. Additionally, the proportions of neurons containing calbindin D-28K and parvalbumin immunoreactivity as well as their protein levels were determined. Fertilized eggs of domestic chick were incubated under normal conditions of temperature, humidity, forced draft of air as well as light and dark (12:12 h) photoperiods. They were exposed to patterned sounds of species-specific and sitar music at 65 dB for 15 min per hour over a day/night cycle from day 10 of incubation till hatching. The hippocampal volume, neuronal nuclear size and total number of neurons showed a significant increase in the music-stimulated group as compared to the species-specific sound-stimulated and control groups. However, in both the auditory-stimulated groups the protein levels of calbindin and parvalbumin as well as the percentage of the immunopositive neurons were increased. The enhanced proportion of CaBPs in the sound-enriched groups suggests greater Ca²⁺ influx, which may influence long-term potentiation and short-term memory.     

A Recombinant Fragment of Human Surfactant Protein D Lacking the Short Collagen‐Like Stalk Fails to Correct Morphological Alterations in Lungs of SP‐D Deficient Mice

Emphysema‐like pathology is a characteristic feature of surfactant protein D (SP‐D) knock‐out mice. Treatment with a recombinant fragment of human SP‐D consisting of a short collagen‐like stalk (but not the entire collagen‐like domain of native SP‐D), neck, and carbohydrate recognizing domain (CRD) inhibits development of emphysema‐like pathology in SP‐D deficient mice. On the other hand, it has been shown that the entire collagen‐like domain is necessary for preventing SP‐D knock‐out mice from pulmonary emphysema development. Thus, in the present study, we aimed to elucidate the role of the short collagen‐like stalk for the function of the recombinant fragment of human SP‐D. We treated SP‐D knock‐out mice with a fragment of human SP‐D lacking the short collagen‐like stalk and compared the effects on lung morphology with results from untreated wild‐type and SP‐D knock‐out mice and from SP‐D knock‐out mice treated with a recombinant fragment of human SP‐D including the short collagen‐like stalk. The fragment of SP‐D lacking the short collagen‐like stalk failed to correct pulmonary emphysematous alterations demonstrating the importance of the short collagen‐like stalk for the biological activity of the recombinant fragment of human SP‐D. Anat Rec, 2009. © 2008 Wiley‐Liss, Inc.     

Human mast cells costimulate T cells through a CD28‐independent interaction

Mast cells are innate immune cells usually residing in peripheral tissues, where they are likely to activate T‐cell responses. Similar to other myeloid immune cells, mast cells can function as antigen‐presenting cells. However, little is known about the capacity of human mast cells to costimulate CD4⁺ T cells. Here, we studied the T‐cell stimulatory potential of human mast cells. Peripheral blood derived mast cells were generated and cocultured with isolated CD4⁺ T cells. In the presence of T‐cell receptor triggering using anti‐CD3, mast cells promoted strong proliferation of T cells, which was two‐ to fivefold stronger than the “T‐cell promoting capacity” of monocytes. The interplay between mast cells and T cells was dependent on cell–cell contact, suggesting that costimulatory molecules on the mast cell surface are responsible for the effect. However, in contrast to monocytes, the T‐cell costimulation by mast cells was independent of the classical costimulatory molecule CD28, or that of OX40L, ICOSL, or LIGHT. Our data show that mast cells can costimulate human CD4⁺ T cells to induce strong T‐cell proliferation, but that therapies aiming at disrupting the interaction of CD28 and B7 molecules do not inhibit mast cell mediated T‐cell activation.     

Calbindin D28k‐immunoreactive afferent nerve endings in the laryngeal mucosa

The distribution of the calbindin D28k in the laryngeal sensory structures was studied by immunohistochemistry, immunoelectronmicroscopy, and double immunofluorescence with calretinin‐immunoreactivity. Moreover, origin of the nerve endings were observed using retrograde tracer, fast blue. Immunoreactivity for calbindin D28k was found in the various types of nerve endings in the larynx, namely, laminar nerve endings, nerve endings associated with the taste buds, intraepithelial nerve endings, and endocrine cells. The laminar endings with calbindin D28k‐immunoreactivity were observed in the subepithelial connective tissue. In some endings, terminals were expanded. The laminar endings were also observed in the perichondrium of the epiglottic cartilage. In the epiglottic and arytenoid epithelia, thick nerve fibers with calbindin D28k‐immunoreactivity ascending to taste buds and intragemmal nerve fibers were also observed. Within the epithelial layer, intraepithelial free nerve endings with calbindin D28k‐immunoreactivity were observed. Furthermore, diffuse endocrine cells were observed within the laryngeal epithelium. By immunoelectron microscopy, immunoreaction products in the endings mentioned above were localized in the cytoplasm of the axon terminals and nerve fibers which contained with numerous mitochondria. Out of the 100 laminar endings, 18 endings were immunopositive for both calbindin D28k and calretinin, 33 were positive for calbindin D28k but negative for calretinin, and 49 were positive for only calretinin in the double immunofluorescence microscopy. The nerve fibers associated with the taste buds and the free nerve endings, which immunostained for calbindin D28k, were not stained with antibody against calretinin. After injection of the fast blue in the laryngeal mucosa, fast blue‐labeled cells were mainly observed in the nodose ganglia. Of the total number of labeled cell in the nodose and dorsal root ganglia at the level C1 to Th2, 65.1% occurred in nodose ganglia (572/879, n = 6). In the nodose ganglia, 79.7% of labeled cells (456/572) were immunoreacted for calbindin D28k. The distribution of calbindin D28k‐immunoreactivity may be differnt from that of calretinin. It is suggested that calbindin D28k have regulatory role on intracellular calcium concentration in the laryngeal sensory corpuscles. Anat Rec 259:237–247, 2000. © 2000 Wiley‐Liss, Inc.     

3D variable‐density SPARKLING trajectories for high‐resolution T2*‐weighted magnetic resonance imaging

We have recently proposed a new optimization algorithm called SPARKLING (Spreading Projection Algorithm for Rapid K‐space sampLING) to design efficient compressive sampling patterns for magnetic resonance imaging (MRI). This method has a few advantages over conventional non‐Cartesian trajectories such as radial lines or spirals: i) it allows to sample the k‐space along any arbitrary density while the other two are restricted to radial densities and ii) it optimizes the gradient waveforms for a given readout time. Here, we introduce an extension of the SPARKLING method for 3D imaging by considering both stacks‐of‐SPARKLING and fully 3D SPARKLING trajectories. Our method allowed to achieve an isotropic resolution of 600 μm in just 45 seconds for T2? ‐weighted ex vivo brain imaging at 7 Tesla over a field‐of‐view of 200 × 200 × 140 mm³ . Preliminary in vivo human brain data shows that a stack‐of‐SPARKLING is less subject to off‐resonance artifacts than a stack‐of‐spirals.