[Genotype-phenotype analysis of Fabry disease caused by GLA gene variation in a pedigree]

Objective: To investigate the clinical phenotype and genetic characteristics of patients with Fabry disease caused by a GLA variant, IVS4+919G>A. Methods: It was a prospective study. Fabry disease screening was conducted among high-risk population in Ninghai from October 2021 to August 2023. Those children with decreased α-galactosidase enzyme activity<2.40 μmol/(L·h) or elavated Lyso-GL-3 level>1.10 μg/L in dried blood spot (DBS) method underwent GLA genetic testing for diagnosis confirmation. Meanwhile, family screening was carried out. A proband and his family members diagnosed with Fabry disease were research subjects. The clinical and genetic characteristics of patients with Fabry disease caused by the GLA variant (IVS4+919G>A) were analyzed. Results: The female proband aged 9.8 years with pain in both lower limbs as the initial symptom was found to have a heterozygous GLA variant IVS4+919G>A among 102 patients. In family screening, there were 4 family members (proband's father, elder sister, elder male cousin and elder female cousin) with Fabry disease and a family member (proband's fifth aunt) with a GLA variant. Among these 4 diagnosed family members, the elder male cousin of the proband, a boy aged 13.2 years had a heterozygous GLA variant, IVS4+919G>A with intermittent pain in both lower limbs as the initial symptom. The proband's father had knee joint pain. The proband's elder sister had decreased vision and his elder female cousin had no obvious symptoms. The proband's fifth aunt with a GLA variant had decreased vision. Conclusions: High-risk screening in children and family screening are helpful for early diagnosis and treatment of Fabry disease. Neuropathic pain may be a early symptom in children with Fabry disease caused by the GLA variant, IVS4+919G>A.

[Measurement of corneal nerve fiber parameters in patients with Parkinson's disease]

Objective: To analyze the characteristic changes of corneal nerve fibers in patients with Parkinson's disease (PD) by corneal confocal microscopy (CCM) and investigate the association of corneal nerve fiber parameters with disease severity and motor symptoms. Methods: Forty-two patients with PD were recruited from the Department of Neurology, Henan University People's Hospital from June 2018 to October 2019. Meanwhile, 40 healthy controls who visited the hospital for physical examination at the same period were enrolled. Corneal nerve fibers in both eyes of all participants were detected by using CCM. The differences of corneal nerve fibers were comparatively analyzed between PD group and healthy controls. Associations of corneal nerve parameters with clinical characteristics such as course of disease, Hoehn and Yahr stage (H-Y stage), unified Parkinson disease rating scale (UPDRS), levodopa equivalent daily dosage (LEDD) were analyzed by using partial correlations. The receiver operating characteristic (ROC) curve was used to analyze the capability of corneal nerve fibers for distinguishing patients with PD from healthy controls. Results: Corneal nerve fiber density (CNFD) in PD group ((19±3)/mm²) was significantly decreased compared with healthy controls ((28±4)/mm²) (t=10.798, P<0.001). However, corneal nerve branch density (CNBD) was significantly increased in PD group ((25±11)/mm²) compared with healthy controls ((18±6)/mm²) (t=-3.427, P=0.001). Meanwhile, corneal nerve fiber length (CNFL) was decreased in PD group ((11.0±2.5) mm/mm²) in comparison with healthy controls ((12.5±1.6) mm/mm²) (t=3.139, P=0.002). ROC curve analysis revealed that CNFD could discriminate PD patients from healthy controls, with an area under the curve of 0.961 3 (95%CI: 92.42-99.84, P<0.000 1). CNFD was negatively correlated with H-Y stage and UPDRS-Ⅲ (r=-0.501 and -0.399, both P<0.05). CNBD was significantly negatively associated with H-Y stage, UPDRS-Ⅲ and UPDRS-Total (r=-0.622, -0.394 and -0.354, respectively, all P<0.05). CNFL was negatively correlated with H-Y stage, UPDRS-Ⅲ and UPDRS-total (r=-0.574, -0.484 and -0.422, respectively, all P<0.05). Conclusion: Small nerve fiber injuries exist in PD patients. Corneal nerve fibers negatively correlates with motor symptoms. CNFD have a good discriminative power to distinguish PD patients from healthy controls and may serve as a marker for PD.

[Depletion of PRDM9 inhibited the osteogenic differentiation potential of periodontal ligament stem cells]

Objective: To investigate the effect of PR domain zinc finger protein 9 (PRDM9), one of the histone methylated transferases, on osteogenic differentiation ability of periodontal ligament mesenchymal stem cells (PDLSC). Methods: PDLSC with PRDM9 gene knocked down by PRDM9 shRNA using recombinant lentiviral vector were allocated into the PRDM9sh group, and the transfected shRNA was as the control group. The gene expression efficiency was evaluated by reverse transcription polymerase chain reaction (RT-PCR). Alkaline phosphatase activity (ALP), alizarin red staining, mineralization and osteocalcin, which belongs to osteogenic differentiation markers detected by RT-PCR and Western blotting to detect the osteogenic differentiation ability of stem cells from periodontal ligaments in vitro. In vivo, PRDM9sh and control group cells was transplanted into the dorsal dermal to explore the osteogenesis. The area percentage of new osteogenic tissue was calculated by image pro software and statistically analyzed. Results: RT-PCR results showed that the relative expression of PRDM9 gene in PRDM9sh (0.460±0.017) was significantly lower than that in control group (1.000±0.107) (P<0.05). The results of ALP activity determined at 5 days postinduction in a significant decrease in PRDM9sh cells (0.762±0.063) compared with control group (1.225±0.058) (P<0.01). Alizarin red staining induced by osteogenesis at 2 weeks and 3 weeks showed that the staining of PRDM9sh was significantly lighter than that in control group. Quantitative calcium analysis results showed that the calcium ion concentration induced by osteogenesis at 2 weeks and 3 weeks [(0.071±0.004), (0.075±0.001)] in PRDM9sh was significantly lower than that in control group at 2 weeks and 3 weeks [(0.282±0.006), (0.485+0.004)] (P<0.01). RT-PCR results showed that the relative expression of osteocalcin mRNA in PRDM9sh (1.059±0.148) was significantly lower than that in control group at 2 weeks (2.542±0.190) (P<0.01). Western blotting results showed that osteocalcin expression in PRDM9sh was significantly lower than that in control group at 1 and 2 weeks after osteogenesis induction. Animal transplantation experiments results indicated that PRDM9 significantly inhibited the osteogenesis of PDLSC in vivo, and the proportion of osteogenic area calculated showed that the osteogenic capacity of PRDM9sh [(3.8±2.41)%] was significantly lower than that in control group [(24.54±7.06)%](P<0.05). Conclusions: Depletion of PRDM9 repressed the osteogenic differentiation of stem cells from periodontal ligament in vitro and in vivo.

[Retrospective analysis of 13 cases of nocardiosis]

Objective: To evaluate the clinical features, chest radiological manifestations, microbiological examination and treatments of nocardial disease. Methods: A retrospective study was conducted to analyze the data of patients with nocardial infection admitted to Beijing Chaoyang Hospital from January 2010 to January 2016. Results: The 13 patients, 6 males and 7 females, aged (51±17) years. Twelve cases were diagnosed with pulmonary nocardiosis, and 1 with disseminated nocardial infection. Most of these patients had complications: autoimmune diseases in 3 (2 with autoimmune hemolytic anemia and 1 with systemic lupus erythematosus), and bronchiectasis in 6 patients. The most common symptoms were cough, expectoration and fever. The main manifestations of CT scans included nodules or masses, bronchiectasis, ground glass opacity, cavity and pleural thickening. Six cases were confirmed by sputum smear microscopy, 4 by bronchoalveolar lavage, 2 by percutaneous lung biopsy and 1 by renal abscess puncture. After diagnosis, antibiotics such as Co-trimoxazole, amikacin, cephalosporins, imipenem, minomycin, or linezolid were used, and the 13 patients were all cured and discharged. Conclusions: Pulmonary nocardiosis was the most common clinical presentation of nocardial infection. Cough, expectoration and fever were the most common symptoms. The main findings of CT scans were nodules or masses, bronchiectasis, ground glass opacity, cavity and pleural thickening. The diagnosis of nocardiosis was not easy because of the non-specific clinical presentations and difficult culture of nocardia spp. Thus, high clinical suspicion of nocardiosis is necessary for earlier diagnosis and treatment.

[Correlation between ultrasonographic optic nerve sheath diameter and intracranial pressure]

Objective: To evaluate the association of the ultrasonographic optic nerve sheath diameter (ONSD) and intracranial pressure (ICP), and the feasibility of ultrasonographic ONSD in predicting high ICP. Methods: A prospective study. The outpatients who planned to measure ICP by lumbar puncture in Department of Neurology, Xuanwu Hospital, Capital Medical University were selected from January 2011 to May 2012. All the retrobulbar ONSD measurement with B-scan ultrasound was performed just before lumbar puncture. When high ICP was defined as ICP more than 200 mmH₂O(1 mmH₂O=0.009 8 kPa), the participants were divided into the high ICP group and the normal ICP group. The Pearson correlation coefficient analysis was used to analyze the correlation between ICP and postbulbar ONSD measurements. The difference in ONSD was compared between the high ICP and normal ICP groups with the t test. The receiver operating characteristic (ROC) curve was used to calculate the cutoff value of mean ONSD and evaluate the sensitivity and specificity of the method. Results: A total of 130 participants were involved in this study. There were 71 males and 59 females, aged (38±14) years.The mean ICP was (209.84±79.99) mmH₂O. The mean ONSD was (5.68±0.78) mm in the right eyes, (5.78±0.78) mm in the left eyes, and (5.73±0.71) mm in both eyes. The ICP had a significant correlation with ONSD in the right eyes (r=0.54, P<0.001), ONSD in the left eyes (r=0.56, P<0.001) and ONSD in both eyes (r=0.60, P<0.001), but no correlation with age (r=-0.14, P=0.114) and gender (r=0.20, P=0.817). The ONSD in the high ICP group (n=65) was (6.11±0.66) mm, (6.22±0.56) mm and (6.17±0.50) mm in the right eyes, left eyes, and both eyes, respectively. Compared with the ONSD in the normal ICP group (n=65), which was (5.26±0.64) mm in the right eyes, (5.34±0.72) mm in the left eyes and (5.30±0.62) mm in both eyes, there was a significantly enlarged ONSD in the high ICP group (t=-7.507, -7.778, -8.779, all P<0.001). The ROC analysis showed the ONSD of 5.6 mm was the best cutoff value with a sensitivity of 86% and a specificity of 71% for identifying high ICP. Conclusions: There is a significantly positive correlation between ICP and postbulbar ONSD measured by ultrasound. This non-invasive method may be an alternative approach to predicting the ICP value of patients whose ICP measurement via lumbar puncture is at high risk. However, it can not replace the direct ICP measurement with the invasive method. (Chin J Ophthalmol, 2018, 54: 683-687).

[Effects of hydrogen sulfide on root architecture, leaf reactive oxygen and photosynthetic characteristics of Malus hupehensis under waterlogging.]

The root architecture, leaf reactive oxygen species and photosynthetic characteristics of potted Malus hupehensis seedlings were investigated after 10 days of waterlogging under five concentrations of hydrogen sulfide (H2S) donor sodium hydrosulfide (NaSH, 0, 0.02, 0.05, 0.1, 0.2 mmol·L^-1) and NaSH with scavenger hypotaurine (HT). The results showed that the root length, root surface area, root volume, root diameter, root top number, fractal dimension, first lateral roots and root activity all increased, the leaf superoxide anion (O2^-_·) accumulation and hydrogen pero-xide (H2O2) content both decreased, the leaf P_n, T_r, g_s, WUE and CUE all raised, the plant height and biomass both increased when the 0.02-0.1 mmol·L^-1 NaHS were added to the waterlogging environment. Adding 0.1 mmol·L^-1 NaHS showed the best effects. All these parameters dropped back to the level of waterlogging alone when NaHS concentration was 0.2 mmol·L^-1 or HT was added to the 0.1 mmol·L^-1 NaHS solution. These suggested that applying an appropriate amount of H2S could effectively alleviate the inhibition of soil waterlogging on the root growth of M. hupehensis and relieve the effects of waterlogging stress on photosynthesis and plant growth by reducing the production of reactive oxygen species and increasing CUE.

[Effects of different mulching materials on nitrate metabolism in soil of apple root-zone in summer and autumn.]

This study explored the effects of mulching straw mat, agricultural carpet, transparent-plastic film and horticultural fabric on nitrification-denitrification, nitrate reductase (NR), nitrite reductase (NiR), ammonium, nitrate and nitrite nitrogen in root-zone soil grown with three-year old apple trees (Malus domestica cv. Starkrimson) during summer and autumn. Results showed that the four treatments decreased nitrification intensity in summer soil, NiR activity in summer-autumn soil and the variation coefficient of nitrification-denitrification intensity and NR in both summer and autumn soil. The treatments increased the denitrification intensity, NR activity, ammonium nitrogen contents in summer-autumn soil and ammonium nitrogen contents in autumn soil. Straw mat treatment increased denitrification intensity and nitrate nitrogen contents in both summer and autumn soil and decreased the activity of NR and NiR in summer soil. The coefficient of variation of nitrification-denitrification intensity and NR activity treated by mulching straw mat was lower than those in the other treatments in both summer and autumn soil. Agricultural carpet increased the NR and NiR activity in summer soil, the nitrate nitrogen contents in summer-autumn soil and the denitrification intensity in autumn soil and decreased denitrification intensity in summer soil. Transparent-plastic film increased the nitrite nitrogen contents in summer soil, the contents of nitrate nitrogen in summer-autumn soil, the nitrification intensity and NiR activity in autumn soil, and decreased nitrate nitrogen contents in summer soil. Horticultural fabric increased denitrification intensity in summer soil, nitrification intensity in summer-autumn and autumn soil and the nitrate nitrogen contents in autumn soil. The four mulching treatments all promoted plant growth. In the four mulching treatments, the new shoot and trunk thickening growth were more under straw mat and horticultural fabric treatments. The four mulching treatments had different effects on nitrate metabolism in summer and autumn soil, but they were able to stabilize the soil nitrate metabolism and transformation. Among the treatments, straw mat had the best stable effect.

Brief reports: TRPM7 Senses mechanical stimulation inducing osteogenesis in human bone marrow mesenchymal stem cells

Mesenchymal stem cells (MSCs) are multipotential stem cells residing in the bone marrow. Several studies have shown that mechanical stimulation modulates MSC differentiation through mobilization of second messengers, but the mechanism of mechanotransduction remains poorly understood. In this study, using fluorescence and laser confocal microcopy as well as patch-clamp techniques, we identified the transient receptor potential melastatin type 7 (TRPM7) channel as the key channel involved in mechanotransduction in bone marrow MSCs. TRPM7 knockdown completely abolished the pressure-induced cytosolic Ca(2+) increase and pressure-induced osteogenesis. TRPM7 directly sensed membrane tension, independent of the cytoplasm and the integrity of cytoskeleton. Ca(2+) influx through TRPM7 further triggered Ca(2+) release from the inositol trisphosphate receptor type 2 on the endoplasmic reticulum and promoted NFATc1 nuclear localization and osteogenesis. These results identified a central role of TRPM7 in MSC mechanical stimulation-induced osteogenesis.

Molecular cloning, sequence analysis, prokaryotic expression, and function prediction of foot-specific peroxidase in Hydra magnipapillata Chinese strain

The cDNA sequence of foot-specific peroxidase PPOD1 from the Chinese strain of Hydra magnipapillata was cloned by reverse transcription-polymerase chain reaction. The cDNA sequence contained a coding region with an 873-bp open reading frame, a 31-bp 5'-untranslated region, and a 36-bp 3'-untranslated region. The structure prediction results showed that PPOD1 contains 10.34% of α-helix, 38.62% of extended strand, 12.41% of β-turn, and 38.62% of random coil. The structural core was α-helix at the N terminus. The GenBank protein blast server showed that PPOD1 contains 2 fascin-like domains. In addition, high-level PPOD1 activity was only present in the ectodermal epithelial cells located on the edge of the adhesive face of the basal disc, and that these cells extended lamellipodia and filopodia when the basal disc was tightly attached to a glass slide. The fascin-like domains of Hydra PPOD1 might contribute to the bundling of the actin filament of these cells, and hence, the formation of filopodia. In conclusion, these cells might play an important role in strengthening the adsorbability of the basal disc to substrates.

Potential sources of carcinogenic heterocyclic amines in the Chinese diet: results from a 24-h dietary recall study in Singapore

OBJECTIVE

Heterocyclic amines (HCAs) from high-temperature cooking of meat have been linked to increased cancer incidence in Western populations, but data on the sources of HCAs in Asian diets are scarce. Our aim was to identify potential sources of HCAs in the Chinese diet, and to provide the basis for efforts to quantify dietary exposure to these compounds.

DESIGN AND SETTING

We conducted 24-h dietary recall interviews among 986 Chinese men and women in Singapore, who were a randomly selected subpopulation of participants from the Singapore Chinese Health Study, a population-based cohort. Details of all foods and beverages consumed by each subject in the past 24 h were recorded, and information on meat type, cooking method and portion size were abstracted from all meat-containing dishes, and gram weight equivalents computed.

RESULTS

The mean meat intake per person was 103.0 g/day (standard deviation 74.2), of which 97.2% was fresh meat. Fish (38.0%), pork (30.6%), and poultry (21.0%) accounted for 89.6% of meat consumed. Patterns of meat consumption and cooking methods differed markedly from Western populations. Documented high-temperature cooking methods, combined with stir-frying, accounted for 44.3% of fish, 35.1% of pork and 25.6% of poultry consumed. Specifically, potentially significant sources of HCAs were pan-fried fish and barbecued pork.

CONCLUSIONS

Our results identify the potential sources of HCA in the Chinese diet, highlight aspects which are relevant to HCA formation and intake, and call for novel approaches to estimating individual exposure to dietary HCAs in this and similar populations.

The signaling mechanism of Arabidopsis CRY1 involves direct interaction with COP1

Dark-grown transgenic Arabidopsis seedlings expressing the C-terminal domains (CCT) of the cryptochrome (CRY) blue light photoreceptors exhibit features that are normally associated only with light-grown seedlings, indicating that the signaling mechanism of Arabidopsis CRY is mediated through CCT. The phenotypic properties mediated by CCT are remarkably similar to those of the constitutive photomorphogenic1 (cop1) mutants. Here we show that Arabidopsis cryptochrome 1 (CRY1) and its C-terminal domain (CCT1) interacted strongly with the COP1 protein. Coimmunoprecipitation studies showed that CRY1 was bound to COP1 in extracts from both dark- and light-grown Arabidopsis. An interaction also was observed between the C-terminal domain of Arabidopsis phytochrome B and COP1, suggesting that phytochrome signaling also proceeds, at least in part, through direct interaction with COP1. These findings give new insight into the initial step in light signaling in Arabidopsis, providing a molecular link between the blue light receptor, CRY1, and COP1, a negative regulator of photomorphogenesis.

The signaling mechanism of Arabidopsis CRY1 involves direct interaction with COP1

Dark-grown transgenic Arabidopsis seedlings expressing the C-terminal domains (CCT) of the cryptochrome (CRY) blue light photoreceptors exhibit features that are normally associated only with light-grown seedlings, indicating that the signaling mechanism of Arabidopsis CRY is mediated through CCT. The phenotypic properties mediated by CCT are remarkably similar to those of the constitutive photomorphogenic1 (cop1) mutants. Here we show that Arabidopsis cryptochrome 1 (CRY1) and its C-terminal domain (CCT1) interacted strongly with the COP1 protein. Coimmunoprecipitation studies showed that CRY1 was bound to COP1 in extracts from both dark- and light-grown Arabidopsis. An interaction also was observed between the C-terminal domain of Arabidopsis phytochrome B and COP1, suggesting that phytochrome signaling also proceeds, at least in part, through direct interaction with COP1. These findings give new insight into the initial step in light signaling in Arabidopsis, providing a molecular link between the blue light receptor, CRY1, and COP1, a negative regulator of photomorphogenesis.

An Arabidopsis circadian clock component interacts with both CRY1 and phyB

Most organisms, from cyanobacteria to mammals, use circadian clocks to coordinate their activities with the natural 24-h light/dark cycle. The clock proteins of Drosophila and mammals exhibit striking homology but do not show similarity with clock proteins found so far from either cyanobacteria or Neurospora. Each of these organisms uses a transcriptionally regulated negative feedback loop in which the messenger RNA levels of the clock components cycle over a 24-h period. Proteins containing PAS domains are invariably found in at least one component of the characterized eukaryotic clocks. Here we describe ADAGIO1 (ADO1), a gene of Arabidopsis thaliana that encodes a protein containing a PAS domain. We found that a loss-of-function ado1 mutant is altered in both gene expression and cotyledon movement in circadian rhythmicity. Under constant white or blue light, the ado1 mutant exhibits a longer period than that of wild-type Arabidopsis seedlings, whereas under red light cotyledon movement and stem elongation are arrhythmic. Both yeast two-hybrid and in vitro binding studies show that there is a physical interaction between ADO1 and the photoreceptors CRY1 and phyB. We propose that ADO1 is an important component of the Arabidopsis circadian system.

The C termini of Arabidopsis cryptochromes mediate a constitutive light response

Cryptochrome blue light photoreceptors share sequence similarity to photolyases, flavoproteins that mediate light-dependent DNA repair. However, cryptochromes lack photolyase activity and are characterized by distinguishing C-terminal domains. Here we show that the signaling mechanism of Arabidopsis cryptochrome is mediated through the C terminus. On fusion with beta-glucuronidase (GUS), both the Arabidopsis CRY1 C-terminal domain (CCT1) and the CRY2 C-terminal domain (CCT2) mediate a constitutive light response. This constitutive photomorphogenic (COP) phenotype was not observed for mutants of cct1 corresponding to previously described cry1 alleles. We propose that the C-terminal domain of Arabidopsis cryptochrome is maintained in an inactive state in the dark. Irradiation with blue light relieves this repression, presumably through an intra- or intermolecular redox reaction mediated through the flavin bound to the N-terminal photolyase-like domain.

The tyrosine kinase c-Abl regulates p73 in apoptotic response to cisplatin-induced DNA damage

Cancer chemotherapeutic agents such as cisplatin exert their cytotoxic effect by inducing DNA damage and activating programmed cell death (apoptosis). The tumour-suppressor protein p53 is an important activator of apoptosis. Although p53-deficient cancer cells are less responsive to chemotherapy, their resistance is not complete, which suggests that other apoptotic pathways may exist. A p53-related gene, p73, which encodes several proteins as a result of alternative splicing, can also induce apoptosis. Here we show that the amount of p73 protein in the cell is increased by cisplatin. This induction of p73 is not seen in cells unable to carry out mismatch repair and in which the nuclear enzyme c-Abl tyrosine kinase is not activated by cisplatin. The half-life of p73 is prolonged by cisplatin and by co-expression with c-Abl tyrosine kinase; the apoptosis-inducing function of p73 is also enhanced by the c-Abl kinase. Mouse embryo fibroblasts deficient in mismatch repair or in c-Abl do not upregulate p73 and are more resistant to killing by cisplatin. Our results indicate that c-Abl and p73 are components of a mismatch-repair-dependent apoptosis pathway which contributes to cisplatin-induced cytotoxicity.

Three-dimensional coupled fluid-structure simulation of pericardial bioprosthetic aortic valve function

A computational, three-dimensional coupled fluid-structure dynamics model was developed for a generic pericardial aortic valve in a rigid aortic root graft with physiologic sinuses. Valve geometry was based on that of the natural valve. Blood flow was modeled as pulsatile, laminar, Newtonian, incompressible flow. The structural model accounted for material and geometric nonlinearities and also simulated leaflet coaptation. A body fitted grid was used to subdivide the flow domain into computational finite volume cells. Shell finite elements were used to discretize the leaflet volume. A finite volume computational fluid dynamics code and finite element structure dynamics code were used to solve the flow and structure equations, respectively. The fluid flow and structural equations were coupled using an implicit "influence coefficient" technique. Physiologic ventricular and aortic pressure waveforms were prescribed as the flow boundary conditions. The aortic flow field, valve structural configuration, and leaflet stresses were computed at 2 msec intervals. Model predictions on aortic flow and transient variation in valve orifice area were in close agreement with corresponding experimental in vitro data. These findings suggest that the computer model has potential for being a powerful design tool for bioprosthetic aortic valves.

Apoptosis of human glioma cells in vitro and in vivo induced by a neutralizing antibody against human basic fibroblast growth factor

Basic fibroblast growth factor (bFGF) is mitogenic to neuroectoderm- and mesoderm-derived cells and is a potent angiogenic factor. Abundant amounts of this factor and its receptor are detected in human glioma tissues and cells, and bFGF in glioma is thought to be involved in autonomous cell growth as an autocrine growth factor. A neutralizing mouse monoclonal antibody (MAb) against bFGF, 3H3 MAb, has been shown to inhibit both in vitro and in vivo growth of human glioma cell lines. This study shows that the human glioma cell lines U-87MG and U-251MG, which express high levels of bFGF and its receptor, can be induced to undergo apoptosis when cultured with 3H3 MAb. It is also demonstrated that 3H3 MAb can cause apoptosis in the same glioma cells that were transplanted into nude mice. Furthermore, enforced overexpression of bcl-2 protein by gene transfection prevented 3H3 MAb-induced apoptosis of glioma cells. It is concluded that induction of apoptosis by the neutralizing antibody is a promising therapeutic strategy for glioma.

Preference of calcium-dependent interactions between calmodulin-like domains of calpain and calpastatin subdomains

Calpastatin molecule contains four repeated inhibition domains, each having highly conserved internal regions A, B and C. The synthetic oligopeptides of regions A and C had no calpain inhibition activity while region B oligopeptide showed weak inhibition activity. Real-time biomolecular interaction analysis using a BIAcore instrument revealed that the bacterially expressed calmodulin-like domain of the calpain large subunit (L-CaMLD) and that of the small subunit (S-CaMLD) interacted, in a Ca(2+)-dependent fashion, preferentially with the immobilized synthetic oligopeptide of region A and that of region C, respectively. Calmodulin showed no specific binding to these oligopeptides. The tripartite structure of the calpastatin functional domain may confer the specific interactions with the protease domain and the two CaMLDs of calpain.

Amino-terminal conserved region in proteinase inhibitor domain of calpastatin potentiates its calpain inhibitory activity by interacting with calmodulin-like domain of the proteinase

Calpastatin is a widely distributed endogenous inhibitor protein specifically acting on calpain (Ca(2+)-dependent proteinase) and is known to interact with the calmodulin-like domain (CaMLD) of the proteinase in a Ca(2+)-dependent fashion. The calpastatin molecule consists of four inhibitory domains (domains 1-4) with mutually homologous sequences in three regions designated as A, B, and C. Acidic amphiphilic alpha-helical motifs are found in both regions A and C. We investigated the correlation between the calpain inhibition potency and the ability of calpastatin to bind to recombinant CaMLD of the mu-calpain large subunit using various mutant proteins of pig calpastatin domain 1 expressed in Escherichia coli. Substitution of conserved Leu-161 with Pro in region A caused a reduction in activity of both calpain inhibition and CaMLD binding. Additional substitution of Leu-236 with Pro in region C further decreased the calpain inhibitory activity and caused a loss of CaMLD binding ability. The effects of mutation in region C alone on the above activities were smaller than those in region A. Although a mutant of deletion in the entire region B had no calpain inhibitory activity, it retained the CaMLD binding ability. On the other hand, although a region B oligopeptide had a moderate inhibitory activity, it had no CaMLD binding ability. These results suggest that region A has a role in potentiating the inhibitory activity of calpastatin by interacting with CaMLD of calpain to form a tighter complex where region B exerts the inhibitory function.

Analysis of calcium-dependent interaction between amino-terminal conserved region of calpastatin functional domain and calmodulin-like domain of mu-calpain large subunit

Calpain requires Ca2+ both for proteolysis of its substrates and for interaction with its endogenous inhibitor, calpastatin. Although calmodulin-like domains (CaMLDs) of large and small subunits of calpain have been suggested to be the sites for Ca(2+)-dependent interaction with calpastatin, specificity and molecular basis of the interaction have remained unclear. We investigated the interaction between the CaMLD of human mu-calpain large subunit expressed in Escherichia coli and a 19-residue synthetic oligopeptide corresponding to the region A (the amino-terminal conserved acidic region) of one of the four repetitive functional domains of calpastatin. The recombinant CaMLD bound to the oligopeptide immobilized on Sepharose beads in a Ca(2+)-dependent manner. The CaMLD failed in binding to a mutant oligopeptide with one amino acid substitution. Enhancement of fluorescence intensity of a hydrophobic probe, 2-(p-toluidino)naphthalene-6-sulfonate, was observed upon incubating with the CaMLD and further increased by Ca2+. The Ca(2+)-dependent enhancement of fluorescence intensity was strongly suppressed by the wild type oligopeptide, but not by the mutant one. Kinetic experiments were performed with BIAcore where binding of the CaMLD to the oligopeptide immobilized on a biosensor chip was detected as real time signals of surface plasmon resonance. The determined dissociation constant (KD) was 3.1 x 10(-9) M. These results suggest that the region A of calpastatin binds to the CaMLD in a specific manner similar to interactions between calmodulin-binding peptides and calmodulin where hydrophobic properties are known to be important.

An experimental-computational analysis of MHV cavitation: effects of leaflet squeezing and rebound

A combined experimental-computational study was performed to investigate the flow mechanics which could cause cavitation during the squeezing and rebounding phases of valve closure in the 29 mm mitral bileaflet Edwards-Duromedics (ED) mechanical heart valve (MHV). Leaflet closing motion was measured in vitro, and input into a computational fluid mechanics software package, CFD-ACE, to compute flow velocities and pressures in the small gap space between the occluder tip and valve housing. The possibility of cavitation inception was predicted when fluid pressures dropped below the saturated vapor pressure for blood plasma. The computational analysis indicated that cavitation is more likely to be induced during valve rebound rather than the squeezing phase of valve closure in the 29 mm ED-MHV. Also, there is a higher probability of cavitation at lower values of the gap width at the point of impact between the leaflet tip and housing. These predictions of cavitation inception are not likely to be significantly influenced by the water-hammer pressure gradient that develops during valve closure.

Requirement of different subdomains of calpastatin for calpain inhibition and for binding to calmodulin-like domains

Calpain requires Ca2+ for both proteolysis of its substrates and interaction with its endogenous inhibitor, calpastatin. The mechanism of inhibition of calpain by calpastatin has remained unsolved, although Nishimura and Goll [J. Biol. Chem. 266, 11842-11850 (1991)] reported that autolyzed calpain fragments containing calmodulin-like domains (CaMLDs) bound to an immobilized calpastatin column. We investigated the correlation between CaMLD-binding and calpain inhibition using immobilized columns of gene-engineered CaMLDs derived from the human mu-calpain large subunit and various recombinant calpastatin mutants. Among the four internally repetitive inhibitory domains of calpastatin, each having conserved regions A, B, and C, only domains 1 and 4 showed the binding activity. The region B deletion mutant of domain 1, retaining the CaMLD-binding ability, no longer had the calpain inhibition activity, and became susceptible to proteolysis. In contrast, a synthetic oligopeptide of region B with moderate calpain inhibition activity did not bind to the column. Domain 3 acquired the binding ability on substitution of region A with that of domain 1. These results suggest that calpain inhibition and binding to the CaMLDs are not correlated or mediated by different subdomains of calpastatin.

[Inhibitory effect of cysteamine on nociceptive responses of dorsal horn neurons in spinal cord of cats]

The effect of somatostatin depletor cysteamine on the nociceptive responses of neurons in laminae IV-VI of spinal cord was studied in 16 pentobarbitone anesthetized and spinal cord transected (at L1) cats. Intravenous injection of cysteamine (50 mg/kg) markedly inhibited responses of the neurons produced by noxious heating (50 C) of glabrous skin of the plantar region, but not C fibre responses induced by electrical stimulation of unmyelinated fibers of the tibial nerve. However, C responses in 8/13 neurons tested were significantly inhibited by large dose cysteamine (100 mg/kg). Following micropressure ejection of cysteamine (20 psig) into the substantia gelatinosa where somatostatin-containing fibers terminate, heating responses were significantly inhibited in all laminae IV-VI neurons whereas C responses was only weakly inhibited in 7/13 neurons. The results suggest that depletion of spinal somatostatin may be involved in cysteamine-induced inhibition of spinal nociception. The possible mechanism underlying the stronger cysteamine-induced inhibition of heating response was discussed.

Release and depletion of substance P by capsaicin in substantia gelatinosa studied with the antibody microprobe technique and immunohistochemistry

Using an antibody microprobe technique, we have detected substance P release from the region of the substantia gelatinosa of the cat during the first, but not the second, 30 min of topical application of capsaicin (1-3%) to the tibial nerve. Immunohistochemical analysis also showed that substance P-like immunoreactivity was markedly reduced in the superficial layer of the dorsal horn 30 min after application of capsaicin. These results indicate that substance P is released and then depleted from primary afferent central terminals following acute application of capsaicin to the peripheral sensory nerve.

Molecular diversity in amino-terminal domains of human calpastatin by exon skipping

Calpastatin, a specific inhibitor of calpain, consists of a unique N-terminal domain (domain L) and four repetitive calpain-inhibition domains (domains 1-4). Calpastatin cDNA of human was reported to have two deletions in domains L and 1, as compared with that of pig and rabbit. We isolated human calpastatin genomic DNA clones, and the sequence analysis revealed seven exons for domain L and five exons for domain 1. Those deletions in the human cDNA were retained in its genomic DNA as exons 3 and 11. By the reverse transcription polymerase chain reaction method, three calpastatin cDNAs, full-length domains L and 1, and two natural mutants with deletions in either exon 3 or in both exons 3 and 5, were cloned from human fibroblast WI-38 cell line mRNA. Domain L was found to be rich in basic amino acid residues, especially for exon 3, and its N-terminal half was highly conserved among species. The isoelectric points (pI) of domain L and domains 1-4 were calculated to be 10.27 and 4.26-4.90, respectively. Moreover, human tissues and cell lines displayed different patterns of reverse transcription polymerase chain reaction products in agarose gel electrophoresis. Therefore, alternative splicing is most likely the cause for the molecular diversity, and the multiple isoforms are implicated for specific physiological roles.

[Inhibition of ohmefentanyl on articular afferent-induced responses of neurons in the spinal lamina X]

In 37 neurons of spinal lamina X, nociceptive responses were evoked by stimulation of the posterior articular nerve (PA) innervating the joint of hindlimb in anesthetized cats. Profound inhibition of nociceptive responses in 73.3% of neurons was induced by ohmefentanyl (1-2 micrograms.kg-1, iv), which was completely reversed by naloxone (80-330 micrograms.kg-1, iv). The results suggested that the mu-opioid receptors was involved in the regulation of transmission of nociceptive information in the spinal lamina X.

Effects of cysteamine on flexion reflex facilitation by C-primary afferents in cats

Brief (20 s) conditioning stimuli at C-fiber intensity applied to the sural or gastrocnemius nerve evoked a facilitation of the flexor alpha-motoneurone discharges from small filaments of the posterior biceps semitendinosus nerve produced by subcutaneous stimulation of the plantar region in anesthetized spinal cats. Such C afferent-induced facilitation was blocked reversibly by cysteamine (50 mg.kg-1), a somatostatin depletor, without affecting the basic mechanisms of flexor reflexes, suggesting an important role played by somatostatin in transmission and/or modulation of nociceptive information in the spinal cord.

Inhibition of nociceptive responses of dorsal horn neurones in the cat spinal cord by ohmefentanyl, a preferring mu opioid receptor agonist [corrected]

An action of ohmefentanyl (OMF), a novel preferring mu opioid receptor agonist, on nociceptive response of the dorsal horn neurone, has been studied in the spinal cat. OMF (0.5-2 micrograms/kg, i.v.) produced a potent naloxone-reversible inhibition of firing of dorsal horn neurones in response to noxious heating of glabrous hindpaw or to impulses in C primary afferents. When ejected into the substantia gelatinosa, OMF produced a relatively selective inhibition of C response, but not A response to excitation of myelinated afferent fibres, of the dorsal horn neurone. An interaction between ohmefentanyl and mu opioid receptors is discussed.

Spermicidal effect in vitro by the active principle of garlic

The in vitro spermicidal effect of Allitridum, an active principle of garlic, was investigated. The data showed that sperm motility was inhibited with various concentrations of Allitridum at different intervals ranging from 20 seconds-200 minutes as compared to control. An obvious immobilization of spermatozoa occurred at 7.5 mg/ml of Allitridum. The effects on sperm motility appeared to be dose-dependent.