Central distribution of efferent and afferent components of the pudendal nerve in rat

Summary Central distribution of efferent and afferent components of the pudendal nerve was examined in the rat by the horseradish peroxidase (HRP) method after HRP application to the central cut end of the pudendal nerve. The pudendal motoneurons were located in the dorsolateral, dorsomedial and lateral groups at L5 and L6. Each of the dorsolateral and dorsomedial groups constituted a slender longitudinal cell column. Pudendal motoneurons in the lateral group were scattered at L5, rostrodorsally to the dorsolateral group. The neurons in the dorsolateral and lateral groups were labelled with HRP applied to the nerve branch innervating the ischiocavernosus and sphincter urethrae muscles. The neurons in the dorsomedial group were labelled with HRP applied to the branch supplying the sphincter ani externus and bulbospongiosus muscles. Some dendrites of pudendal motoneurons in the dorsomedial group extended to the contralateral dorsomedial group. These crossing dendrites were observed not only in male rats but also in female. The average number of the pudendal motoneurons in the dorsolateral and dorsomedial groups were larger in male rats than in female. A few neurons of the intermediolateral nucleus at upper L6 were also labelled with HRP applied to the dorsalis penis (clitoridis) nerve. Axon terminals of the pudendal nerve were distributed, bilaterally with an ipsilateral predominance, to the gracile nucleus, as well as to the dorsal horn and dorsal commissural gray from L4 to S2. A few labelled axons were seen in the intermediolateral nucleus at L6 and S1. Axon terminals from the dorsalis penis nerve were distributed more medially in the dorsal horn than those from the perinealis nerve.     

Glicentin-containing cells in intestinal metaplasia,adenoma and carcinoma of the stomach

Summary Glicentin-containing cells (Glic. cells) in intestinal metaplasia, adenoma and carcinoma of the stomach were examined using immunohistochemical techniques. Glic. cells first occurred in the gastric mucosa of the transitional area between metaplastic and intact gastric glands. They frequently showed hyperplasia or micronoduli in the budding area of the deeper metaplastic glands, but in completely intestinalized mucosa these endocrine cells decreased remarkably. Gastric adenomas with mild dysplasia had a good number of glicentin-immunoreactive cells which were located in the deeper adenoma glands. Gastrin- and somatostatin-positive cells were also detected in the adenomas. The incidence of glicentin-positive tumor cells was significantly higher in well differentiated adenocarcinoma than in poorly differentiated adenocarcinoma. Among the seven cases of scirrhous argyrophil cell carcinoma, three showed glicentin- and glucagon-immunoreactivity in the same area of the tumor. These findings suggest that the selective increase of Glic. cells in intestinal metaplasia may be closely related to the development of gastric adenoma. Glicentin positive tumor cells in gastric carcinomas can be regarded to be an expression of intestinal or fetal markers.     

Integration of retinal and motor signals of eye movements in striate cortex cells of the alert cat

Responses of saccade-depressed (SD) and saccade-excited (SE) cells in the striate cortex to eye movements of alert cats under presentation of a visual pattern were studied under reinforcement of the eye movements with rewards of water. These responses were compared to those on passive displacement of the visual pattern reproducing the movements of the retinal image occurring during eye movements while eye movements were suppressed by withdrawal of reinforcement. Passive displacement of the visual pattern produced in the SD cells depression closely resembled the depression occurring during eye movements under presentation of the visual pattern, in time course as well as in amplitude. Both the saccade depression and the depression due to passive movement of the visual pattern were nonselective to the direction of eye movements. Saccade excitation of the SE cells frequently contained two components occurring at 20 and 80 ms after the onsets of eye movements. Passive displacement of the visual pattern produced in the SE cells excitation comparable with the early component of the saccade excitation. These findings suggest that saccade depression in the SD cells and the early component of the saccade excitation in the SE cells are related to retinal reafference of eye movement. During presentation of visual patterns, saccade excitation in the SE cells was closely related to parameters of eye movements, such as direction, amplitude, duration, and velocity. The correlations were completely lost or strongly reduced in darkness. Lines of evidence were provided that the saccade excitation of the SE cells in darkness or the later component of the saccade excitation under presentation of a visual pattern represents efference copy signals of eye movement transferred to the striate cortex through the Clare-Bishop (CB) cortex. Excitation comparable with saccade excitation in darkness occurred in synchrony with activities of the oculomotor nuclei even after retrobulbar paralysis of eye movement, indicating that the excitation is related to efference copy signals rather than proprioceptive reafference of eye movement.(ABSTRACT TRUNCATED AT 400 WORDS)     

Studies on the interleukin-2 receptor, its generation and dynamics using monoclonal anti-interleukin-2 receptor antibodies

There is increasing evidence suggesting that the monoclonal antibodies ART-18, AMT-13 and anti-Tac recognize species-specific antigenic determinants of the interleukin-2 (IL-2) receptors of rat, mouse and human origin, respectively. In order to compare directly the molecules (glycoproteins) recognized by these antibodies, concanavalin A (ConA) activated T-lymphocytes of the respective species were surface labeled with ¹²⁵I, after which the materials immunoprecipitated by the appropriate anti-IL-2 receptor antibodies were subjected to SDS-PAGE analysis. The noncross-reacting antibodies ART-18 and AMT-13 both precipitated a 50–55-kD molecule. The anti-Tac-reactive material (the putative human IL-2 receptor) is considerably different (60–65 kD) from those precipitated by antibodies ART-18 and AMT-13 (the putative rat and mouse IL-2 receptors). An indirect binding assay using the anti-mouse IL-2 receptor antibody AMT-13 showed that, after addition of ConA to spleen cell cultures, T-lymphocytes expressed IL-2 receptors before the onset of the ConA-induced DNA synthesis. The ConA-induced expression of the IL-2 receptor is apparently a transient event. IL-2 receptor bearing cells progressively lost their receptors (within 6 days) when recultured in the absence of ConA. Cells re-exposed to ConA regained IL-2 receptors. Short exposure of T-cells (thymocytes) to ConA or the nonmitogenic compound phorbol myristate acetate (PMA) is not sufficient to trigger IL-2 receptor expression. Murine thymocytes incubated with PMA for 30 min or with ConA for 4 hr (mitogen-pulsed T-cells) failed to bind the anti-IL-2 receptor antibody AMT-13 and to absorb IL-2 activity present in semipurified IL-2 preparations, but they proliferated vigorously in response to the same IL-2 preparations. The IL-2 preparations, when absorbed with thymocytes, lost: (1) the capacity to generate IL-2 receptors, and (2) the capacity to induce proliferation of mitogen-pulsed cells; but they retained the capacity to induce proliferation of T-lymphoblasts. These results suggest the existence of a factor, IL-2 receptor inducing factor (RIF), present in the IL-2 preparations. It is postulated that RIF is a prerequisite for the acquisition of IL-2 receptors and consequently for IL-2 responsiveness by lectin-activated cells.     

Enamel mineralization and an initial crystalline phase

In this communication, we summarized our recent experimental approaches to an unsettled issue, i.e., the nature and role of an acidic precursor in enamel mineralization. The objectives we specially focused our attention on are: the composition, structure and high resolution images of enamel crystals at various developmental stages, thermodynamic and kinetic consideration of octacalcium phosphate (OCP) vs hydroxyapatite (HA) precipitation in physiological media simulating the enamel fluid, reversible changes in the composition and structure of OCP, effects of fluoride at low concentrations and enamel proteins on OCP hydrolysis, and adsorption of enamel proteins onto OCP and fluoridated hydrolysates at neutral pH and room temperature. On the basis of all experimental evidence, we propose that enamel crystal growth comprises two events: the two-dimensional growth of an OCP-like precursor in a narrow outermost zone adjacent to the ameloblasts and the subsequent overgrowth of apatite units on the template under discrete fluid environment in the underlying region distant from the cell layer. The experimental data also support the concept that the whole process of enamel mineralization is modulated substantially through interaction between enamel proteins and crystals including the acidic precursor.     

Growth hormone releasing hormone receptor (GHRH-r) gene mutation in Indian children with familial isolated growth hormone deficiency: a study from western India

BACKGROUND: Various mutations of the growth hormone releasing hormone receptor (GHRH-R) gene have been recently described to cause familial isolated growth hormone (GH) deficiency (FIGHD), with the GHRH-R nonsense mutation E72X reported in patients with FIGHD from South Asia. The molecular genetic basis of FIGHD in Indian children is not known. Objective: To look for the GHRH-R E72X non-sense mutation in our patients with FIGHD and describe its clinical phenotype. PATIENTS AND METHOD: A total of 31 patients from 22 families diagnosed 4-20 years previously, 20 patients with familial IGHD-IB from 11 families and 11 patients with non-familial isolated GH deficiency (NFIGHD) (phenotypes IGHD-IB in eight patients and -IA in three) were included. Twenty-eight of 31 patients with IGHD-IB came from two states of Western India, 27 of them Hindus from 18 families (three consanguineous) and one from an inbred Moslem kindred. RESULTS: Twenty-two of the patients (71%) (18 FIGHD and four NFIGHD) had a homozygous G-->T transversion in exon 3, with this GHRH-R gene mutation E72X in 90% (18/20) of patients with FIGHD, 36% (4/11) of NFIGHD, altogether 78% (22/28) with phenotype IB. One parent pair with IGHD had homozygous E72X mutation, the rest were heterozygous carriers. Two siblings with IGHD due to homozygous E72X mutation were also heterozygous carriers for GH-1 gene 6.7 kb deletion, inherited from their mother, heterozygous for both GH-1 and GHRH-R mutations. Initial chronological age was 10.89 +/- 3.69 years, bone age 6.4 +/- 3.4 years, and mean height SDS was -5.83 +/- 1.41. The clinical phenotype, with sharp features, lean habitus, lack of frontal bossing or hypoglycemia, was characteristic. The mean peak GH was 1.25 +/- 0.75 ng/ml, IGF-I and IGFBP-3 below -2 SDS with no response to GHRH in those tested. MRI (n = 10) showed pituitary hypoplasia, mean vertical height 2.61 +/- 0.76 mm. Among the other 7/11 NFIGHD patients, four with phenotype IB were negative for genotypes tested in this study; of three patients with phenotype IA, two had the GH-1 gene 6.7 kb deletion, and one was a compound heterozygote with 6.7 and 7.6 kb deletions. CONCLUSIONS: The majority of patients with FIGHD from different communities belonged to non-consanguineous Hindu families from Western India. The GHRH-R gene E72X mutation was found in 71% of this series, in 90% of FIGHD, 36% of NFIGHD, and in 78% with phenotype IB. The characteristic phenotype helped in suspecting this mutation. GHRH-R gene mutations may be the most reasonable candidate for IGHD-IB with the E72X mutation predominating in the Indian subcontinent. More extensive studies need to be undertaken.     

Poor Neorectal Evacuation as a Cause of Impaired Defecatory Function After Low Anterior Resection: A Study Using Scintigraphic Assessment

Purpose. Patients who have undergone low anterior resection (LAR) of the rectum occasionally complain of symptoms related to impaired neorectal evacuation. Using scintigraphy, we assessed neorectal evacuation in 22 patients who underwent LAR and straight anastomosis, and correlated the results with clinical defecatory function, clinical factors, and anorectal manovolumetric parameters. Methods. After the introduction of an artificial stool containing ^99mTc-DTPA into the neorectum, sequential lateral gamma images were obtained. From the time–activity curve of radioactivity in the whole pelvis, the time taken to eva-cuate half of the introduced artificial stool (T _1/2) and the percentage of artificial stool evacuated in 1 min (Evac₁) were calculated. Results. The Evac₁ was significantly lower in the patients who had undergone LAR than in reference normal volunteers. A long T _1/2 was significantly associated with worse defecatory function. The Evac₁ was also significantly lower in patients with a low anastomosis. The rectal sensory threshold was significantly greater in patients with a shorter T _1/2. The maximum tolerable volume of the neorectum was significantly greater in patients with a shorter T _1/2 and a higher Evac₁. Conclusion. Poor neorectal evacuation is associated with impaired defecatory function after LAR. Therefore, it is suggested that optimizing both reservoir function and evacuation of the neorectum would improve defecatory function after LAR. Received: January 19, 2001 / Accepted: July 17, 2001     

Fluorescent probes for intracellular Mg2+ measurement

Recently, fluorescent probes are widely used as tools for dynamical measurement of ion distributions and concentrations in cells. They are highly sensitive, and offer imaging by the use of fluorescent microscopy in easily and less cell damaging way. This paper discusses the selectivity and optical character of the three novel Mg(2+) fluorescent probes. KMG-20AM offers ratiometric quantative measurement of Mg(2+), KMG-104 provides high-sensitive qualitative analysis and 3-D measurement. With those improved Mg(2+) fluorescent probes, the physiological and pathological role of Mg(2+) are going to be more and more clear.     

CT findings of surgically resected large cell neuroendocrine carcinoma of the lung in 38 patients

OBJECTIVE: We sought to assess the CT features of surgically resected large cell neuroendocrine carcinoma of the lung. MATERIALS AND METHODS: The cases of all patients who underwent surgical resection for primary lung cancer in a single institution from 1993 to 2000 and who received an initial diagnosis of poorly differentiated non-small cell lung carcinoma, small cell carcinoma, carcinoid tumor, and large cell neuroendocrine carcinoma were histologically reviewed. The findings for 43 patients were histologically reclassified and confirmed as large cell neuroendocrine carcinoma. The CT scans available for 38 patients were evaluated by two observers. RESULTS: In the 38 patients, six central tumors and 32 peripheral tumors, with diameters ranging from 12 to 92 mm (mean +/- SD, 32 +/- 19 mm), were identified. None of the tumors had air bronchograms or calcification in the mass or nodule. Of the 19 patients with thin-section CT scans, 14 (74%) showed the tumor-lung interface as well defined and five (26%) showed the interface to be ill defined. Lobulation was identified on 15 scans (79%) and spiculation was evident on six scans (32%). On contrast-enhanced CT scans, inhomogeneously enhanced tumors appeared to be larger (51 +/- 18 mm) than homogeneously enhanced tumors (25 +/- 10 mm; p < 0.001). At histopathologic examination, gross necrosis was noted in 20 of 28 patients who had undergone contrast-enhanced CT, and the cause of inhomogeneous enhancement on CT scans was determined to be intratumoral necrosis. Multiple microscopic necroses were present in all 28 patients. CONCLUSION: Large cell neuroendocrine carcinoma usually appears as a well-defined and lobulated tumor with no air bronchograms or calcification. The inhomogeneous enhancement (caused by necrosis) seen in large cell neuroendocrine carcinomas with large diameters is not necessarily apparent in small-diameter (< 33 mm) large cell neuroendocrine carcinomas, even if the tumor contains necrosis.