Calpeptin provides functional neuroprotection to rat retinal ganglion cells following Ca2+ influx

Apoptosis of retinal ganglion cells (RGCs) impairs vision in glaucoma patients. RGCs are also degenerated in multiple sclerosis (MS), resulting in loss of visual perception in MS patients. We examined the involvement of calpain and caspase cascades in apoptosis of the rat retinal ganglion cell line RGC-5 following 24 h of exposure to 250 nM ionomycin (IMN) or 300 units/ml interferon-gamma (IFN-gamma) and then evaluated functional neuroprotection with 2 microM calpeptin (CP, a calpain-specific inhibitor). Morphological and biochemical features of apoptosis were detected in RGC-5 cells following exposure to IMN or IFN-gamma. Fura-2 assay determined significant increases in intracellular free [Ca2+] following exposure to IMN or IFN-gamma. Pretreatment with CP for 1 h prevented Ca2+ influx, proteolytic activities, and apoptosis in RGC-5 cells. Western blot analyses showed an increase in activities of calpain and caspase-12, upregulation of Bax:Bcl-2 ratio, release of cytochrome c from mitochondria, and increase in caspase-9 and caspase-3 activities during apoptosis. Increased caspase-3 activity was also confirmed by a colorimetric assay. Activation of caspase-8 and cleavage of Bid to tBid in RGC-5 cells following exposure to IFN-gamma indicated co-operation between extrinsic and intrinsic pathways of apoptosis. Patch-clamp recordings showed that pretreatment with CP attenuated apoptosis and maintained normal whole-cell membrane potential, indicating functional neuroprotection. Taken together, our results demonstrated that Ca2+ overload could be responsible for activation of calpain and caspase cascades leading to apoptotic death of RGC-5 cells and CP provided functional neuroprotection.     

Effect of capsaicin treatment on nociceptors in rat glabrous skin one day after plantar incision

Dilute capsaicin produces a differential effect on incision-related pain behaviors depending upon the test; it reduces heat hyperalgesia and guarding pain but not mechanical hyperalgesia. This suggests that common mechanisms for heat hyperalgesia and guarding pain occur, and distinct mechanisms exist for mechanical hyperalgesia. The purpose of the present study was to evaluate the effect of capsaicin treatment on the activity of cutaneous nociceptors sensitized by incision to understand the mechanisms for the selective action of dilute capsaicin on incisional pain. We compared the effect of 0.05% capsaicin vs. vehicle treatment on pain behaviors after incision and on the activity of nociceptors from these same rats using the in vitro glabrous skin–nerve preparation. Immunohistochemical expression of protein gene product 9.5 (PGP9.5), neurofilament 200, calcitonin gene related peptide (CGRP) and isolectin B4 (IB4) in skin was also evaluated 1 week after 0.05% capsaicin infiltration. Infiltration of 0.05% capsaicin decreased CGRP and IB4/PGP9.5-immunoreactivity of nociceptors in skin. The same dose of capsaicin that inhibited heat hyperalgesia and guarding behavior interfered with chemo- and heat sensitivity of C-fibers. Neither mechanical hyperalgesia nor mechanosensitivity of nociceptors was affected by capsaicin, suggesting that the concentration of capsaicin used in this study did not cause fiber degeneration. These results demonstrate that nociceptors desensitized by capsaicin contribute to heat hyperalgesia and guarding pain after plantar incision. These putative TRPV1-expressing C-fibers are sensitized to heat and acid after incision, and the transduction of heat and chemical stimuli after plantar incision is impaired by dilute capsaicin.     

Inhalation of [123I]alpha1-protease inhibitor: toward a new therapeutic concept of alpha1-protease inhibitor deficiency?

The alpha1-protease inhibitor (alpha1-Pi) is separated from human serum and is therefore extremely expensive. Because only 2%-3% concentrates in the lung after intravenous administration, inhalational therapy for alpha1-Pi deficiency would seem likely to be better. The aims of this study were therefore to determine the pattern of deposition of inhaled alpha1-Pi labeled with 123I and measure the amount deposited in the lungs. METHODS: Eighteen patients with congenital severe alpha1-Pi deficiency were enrolled in the study. The low-specific-activity 123I-labeled alpha1-Pi aerosol (median particle size +/- SD, 3.9 +/- 2.5 microm) was generated by an air pressure-driven nebulizer. The patients inhaled for an average of 23.6 +/- 8.9 min. Static scintigrams in two projections were acquired immediately after (T1) and 1 (T2), 4 (T3), and 24 h (T4) after inhalation. The patients were divided into the following three groups according to their forced expiratory volume in 1 s (FEV1): group I, < or =40% of predicted normal (n = 8); group II, 40% < FEV1 < or = 60% of predicted normal (n = 4); group III, >60% of predicted normal (n = 6). RESULTS: The absolute percentage uptake values of alpha1-Pi in group I were 12.4 for T1, 7.3 for T2, 4.6 for T3, and 1.2 for T4; in group II the values were 13.0, 9.6, 6.2, and 2.0, respectively; and in group III, 14.6, 11.4, 6.5, and 3.6, respectively. Differences between the groups were generally statistically significant. Between T1 and T2, the probability value was <0.05 for group I versus group II, <0.006 for group I versus group III, and <0.39 for group II versus group III. Between T1 and T3, the probability value was <0.29 for group I versus group II, <0.22 for group I versus group III, and <0.94 for group II versus group III. Retention (between T1 and T4) was also dependent on the grade of the disease: P < 0.2 for group I versus group II, P < 0.001 for group I versus group III, and P < 0.02 for group II versus group III. Grading of the uptake pattern by three independent experienced investigators (87% agreement) revealed a peripheral deposition that was group dependent. We found that greater peripheral deposition corresponded with lower lung functional impairment: P < 0.5 for group I versus group II, P < 0.01 for group I versus group III, and P < 0.08 for group II versus group III. Degradation also corresponded with functional impairment: P < 0.05 for group I versus group II, P < 0.006 for group I versus group III, and P < 0.3 for group II versus group III. CONCLUSION: The results of this study show that sufficient amounts of alpha1-Pi can be deposited in the periphery of the lung by inhalation at least in patients with low-grade disease. Inhalation of alpha1-Pi may thus represent a new and more convenient route of drug administration.     

Landmarking and segmentation of computed tomographic images of pediatric patients with neuroblastoma

Objectives  Segmentation and landmarking of computed tomographic (CT) images of pediatric patients are important and useful in computer-aided diagnosis, treatment planning, and objective analysis of normal as well as pathological regions. Identification and segmentation of organs and tissues in the presence of tumors is difficult. Automatic segmentation of the primary tumor mass in neuroblastoma could facilitate reproducible and objective analysis of the tumor’s tissue composition, shape, and volume. However, due to the heterogeneous tissue composition of the neuroblastic tumor, ranging from low-attenuation necrosis to high-attenuation calcification, segmentation of the tumor mass is a challenging problem. In this context, we explore methods for identification and segmentation of several abdominal and thoracic landmarks to assist in the segmentation of neuroblastic tumors in pediatric CT images. Materials and methods  Methods are proposed to identify and segment automatically peripheral artifacts and tissues, the rib structure, the vertebral column, the spinal canal, the diaphragm, and the pelvic surface. The results of segmentation of the vertebral column, the spinal canal, the diaphragm and the pelvic girdle are quantitatively evaluated by comparing with the results of independent manual segmentation performed by a radiologist. Results and conclusion  The use of the landmarks and removal of several tissues and organs assisted in limiting the scope of the tumor segmentation process to the abdomen, and resulted in the reduction of the false-positive error rates by 22.4%, on the average, over ten CT exams of four patients, and improved the result of segmentation of neuroblastic tumors.     

Serological and genetic characterisation of a unique strain of adenovirus involved in an outbreak of epidemic keratoconjunctivitis

AIMS: To characterise a novel strain of adenovirus (Ad) type Ad8 (genome type Ad8I) involved in an epidemic keratoconjunctivitis (EKC) outbreak in Hiroshima city using serological testing and sequence analysis of the fibre and hexon gene. METHODS: A neutralisation test (NT) was performed in microtitre plates containing a confluent monolayer of A549 cells using 100 tissue culture infectious doses of virus and type specific antisera. The haemagglutination inhibition test was also carried out in microtitre plates with rat erythrocytes using four haemagglutination units of virus and twofold dilutions of serum. The fibre gene was sequenced by generating overlapping polymerase chain reaction products or by direct sequencing of genomic DNA. Primer selection was based on alignment of the fibre genes of human adenovirus serotypes Ad8, Ad19, Ad37, Ad9, and Ad15 available from Gene Bank. RESULTS: The virus strain was specifically neutralised by anti-Ad8 antibodies, although there was a major crossreaction with anti-Ad9 antibodies. Haemagglutination was equally inhibited by anti-Ad8 and anti-Ad9 antibodies. The predicted amino acid sequences of the hypervariable regions (HVRs) of the Ad8I hexon gene showed higher homology with Ad9 (83.3%) than with Ad8 (62.0%). However, the Ad8I fibre knob was more homologous to Ad8 (94.4%) than to Ad9 (91.6%). CONCLUSIONS: Ad8I is a unique strain of adenovirus because of its lower genomic homology with Ad8, major crossreactivity with Ad9 in NT, and mixed genetic organisation of HVRs of the hexon gene. These factors may have enabled the virus to circumvent acquired immunity, resulting in the outbreak.     

Purification of an endogenous 68 kD inhibitor of calcium-activated neutral proteinase (CANP) from bovine brain: immunoblot identification and characterization

A calcium-activated neutral proteinase (CANP)-specific endogenous inhibitor (calpastatin) was purified from bovine brain by successive column chromatography. The purified inhibitor exhibited a major band on sodium dodecylsulfate polyacrylamide gel electrophoresis with an approximate molecular weight of 68 kD. The polyclonal antisera raised to the inhibitor strongly reacted with the 68 kD protein band. Two lightly stained bands approximately 55-68 kD and 120-130 kD were also recognized by the inhibitor antiserum. The inhibitor specifically inhibited CANP activity and the half-maximal inhibition was found with 75 ng of calpastatin per 1 micrograms of CANP in a final volume of 125 microliters. Cathepsin B and papain were not inhibited by the inhibitor, while trypsin and chymotrypsin were inhibited to some extent. The inhibitor formed a complex with CANP and the inactive complex was dissociated into active fractions of enzyme and calpastatin in the presence of EGTA.     

Peptide bond specificity of calpain: Proteolysis of human myelin basic protein

In order to determine the peptide bond specificity of calpain, human myelin basic protein (HMBP) was treated with purified calpain of bovine brain. Upon incubation, HMBP component I (HMBP-1) was degraded into several peptides as demonstrated by sodium dodecy1 sulfate-polyacrylamide gel electrophoresis. Component I was more susceptible to degradation than components II and III. HMBP degradation products were separated by high performance liquid chromatography (HPLC) and the cleavage sites in HMBP molecules were determined by peptide sequence analysis and by N- and C-terminal analyses. The major cleavage site was found to be ⁹⁴Val-⁹⁵ Thr with several minor cleavages at ⁴⁹Arg-⁵⁰Gly, ¹⁸Ala-¹⁹Ser, ²³His-²⁴Ala, ²⁷Gly-²⁸Phe, ⁵⁹Asp-⁶⁰Ser, ⁷⁰Gly-⁷¹Ser, ⁹⁷Arg-⁹⁸Thr, ¹¹⁰Ser-¹¹¹Leu, ¹⁴⁵Asp-¹⁴⁶Ala, and ¹⁵⁶Leu-¹⁵⁷Gly. These results indicate that calpain is involved in the limited proteolysis of human myelin basic protein and prolonged incubation causes further digestion of the large peptides. © 1994 Wiley-Liss, Inc.     

A study on nutrition, growth and development of a high-risk group of children of urban leprosy patients

This paper describes a cross-sectional study of the physical development of a high-risk group of 182 socially deprived healthy children of leprosy patients ranging from preschool age to early teens. They were rescued at the age of 4 years from the distress of leprosy colonies where they were born, and brought up in Government Homes (Preventorium) under better environmental conditions. Of them 135 children could be followed clinically for 10 years for the development of childhood leprosy. Another 94 children of leprosy patients living with their parents were included for comparison. A group of 158 normal children of similar economic status and age group were included as controls. It was observed that, although better environment, food and training were provided in the Preventorium, so that the children could be brought into the national mainstream, nevertheless 5 children developed an indeterminate type of leprosy during the course of 10 years. This is the first report of growth and development of children of leprosy patients from the Indian sub-continent.     

Chronic myokymia limited to the eyelid is a benign condition.

BACKGROUND: Eyelid myokymia, unlike myokymia of the other facial muscles, is assumed to be a benign, self-limited disorder. However, no systematic follow-up study has been performed on patients with chronic, isolated eyelid myokymia to verify its benign nature. METHODS: Retrospective single-institution chart review of 15 patients examined between 1983 and 2002 with a diagnosis of isolated eyelid myokymia who have had at least 12 months of follow-up. RESULTS: In all patients, symptoms began as unilateral, weekly or biweekly, intermittent eyelid spasms, and progressed to daily spasms over several months. The mean duration of symptoms at first examination was 91 months (range 2.5 months to 20 years). In no patient was the myokymia the first manifestation of a neurologic disease, although one patient progressed to ipsilateral hemifacial spasm. Thirteen patients (86.7%) underwent neuroimaging that gave negative results. The myokymia resolved spontaneously in four patients. Of the remaining 11 patients, eight were treated with botulinum toxin injection at regular intervals, with most reporting an improvement in symptoms. CONCLUSION: Chronic isolated eyelid myokymia is a benign condition. It tends not to progress to other facial movement disorders or to be associated with other neurologic disease. It responds well to treatment with botulinum toxin.