Ectopic expression of alpha1,6 fucosyltransferase in mice causes steatosis in the liver and kidney accompanied by a modification of lysosomal acid lipase

The alpha1,6 fucosyltransferase (alpha1,6 FucT) catalyzes the transfer of a fucose from GDP-fucose to the innermost GlcNAc residue of N-linked glycans via an alpha1,6 linkage. alpha1,6 FucT was overexpressed in transgenic mice under the control of a combined cytomegalovirus and chicken beta-actin promoter. Histologically numerous small vacuoles, in which lipid droplets had accumulated, were observed in hepatocytes and proximal renal tubular cells. Electron microscopic studies showed that the lipid droplets were membrane-bound and apparently localized within the lysosomes. Cholesterol esters and triglycerides were significantly increased in liver and kidney of the transgenic mice. Liver lysosomal acid lipase (LAL) activity was significantly lower in the transgenic mice compared to the wild mice, whereas LAL protein level, which was detected immunochemically, was increased, indicating that the specific activity of LAL was much lower in the transgenic mice. In all of the transgenic and nontransgenic mice examined, the activity of liver LAL was negatively correlated with the level of alpha1,6 FucT activity. As evidenced by lectin and immunoblot analysis, LAL was found to be more fucosylated in the transgenic mice, suggesting that the aberrant fucosylation of LAL causes an accumulation of inactive LAL in the lysosomes. Such an accumulation of inactive LAL could be a likely cause for a steatosis in the lysosomes of the liver and kidney in the case of the alpha1,6 FucT transgenic mice.

Effects of sucrose concentration on the developmental potential of human frozen–thawed oocytes at different stages of maturity

BACKGROUND

Success of human oocyte cryopreservation depends on multiple cryobiological factors that could influence the developmental potential of the oocytes. The objective of this study was to examine the effects of different sucrose concentrations on the developmental potential of human frozen-thawed oocytes at different maturity stages.

METHODS

A total of 355 oocytes collected from small follicles were randomly divided into three groups and two groups (B and C) were cryopreserved using slow-freezing method. Group A included 131 oocytes at different maturity stages without freezing. Another 119 oocytes in Group B were cryopreserved with 0.1 M sucrose and 105 oocytes in Group C with 0.2 M sucrose concentration.

RESULTS

The post-thaw survival rate of the oocytes and the cleavage rate in Group C were significantly higher than that of Group B (P<0.05). For immature metaphase I (MI) stage oocytes, a significant difference was found in the maturation rate between Group C and Group B (P<0.05). The maturation rate for the GV oocytes in Groups A and C was significantly higher than Group B (P<0.01).

CONCLUSIONS

The results suggested that sucrose concentration of 0.2 M in the cryoprotectant solution is more suitable for human oocyte cryopreservation.

Beta2-glycoprotein I: target antigen for 'antiphospholipid' antibodies. Immunological and molecular aspects

It has become clear that beta2-glycoprotein I (beta2GPI) is the most common and best-characterised antigenic target for 'antiphospholipid' (aPL) autoantibodies. These antibodies preferentially bind beta2GPI that has been immobilised on anionic phospholipid membranes or certain synthetic surfaces. These surfaces appear to act by increasing antigen density to allow binding of intrinsically low-affinity anti-beta2GPI autoantibodies. Binding of beta2GPI in fluid phase is weak and requires high concentrations of beta2GPI. Our understanding of the pathophysiology of the 'Antiphospholipid' Syndrome (APS) has increased exponentially with the number of studies into the interactions of aPL antibodies and beta2GPI.

Homozygous KIDINS220 loss-of-function variants in fetuses with cerebral ventriculomegaly and limb contractures

Heterozygous mutations in KIDINS220 were recently suggested a cause of spastic paraplegia, intellectual disability, nystagmus and obesity. All patients carried terminal nonsense de novo mutations that seemed to escape nonsense-mediated mRNA decay. The mechanism for pathogenicity is yet unexplained, as it seems that heterozygous loss-of-function variants of KIDINS220 are generally well tolerated. We present a consanguineous couple who experienced four pregnancy terminations due to repeated findings in the fetuses comprising enlarged cerebral ventricles and limb contractures. Exome sequencing in two of the aborted fetuses revealed a shared homozygous frameshift variant in exon 24 in KIDINS220. Sanger sequencing of the variant in available family members showed complete segregation with the affection status, resulting in a LOD score of 2.5 under an autozygous inheritance model. mRNA studies revealed destruction of the original splice site, resulting in an out-of-frame transcript and introduction of a premature termination codon in exon 25. Premature termination codons in this position are likely to cause activation of nonsense-mediated mRNA decay and result in complete absence of KIDINS220 protein in individuals homozygous for the variant. The phenotype of the presented fetuses overlaps with findings in functional studies of knockout Kidins220 mice embryos that are non-viable with enlarged cerebral ventricles. The human fetuses also exhibit several similarities to the milder phenotype described in patients with heterozygous KIDINS220 mutations. We hence propose that the identified homozygous loss-of-function variant in KIDINS220 causes the phenotype in the presented fetuses, and that this represents a hitherto undescribed severe autosomal recessive neurodevelopmental disorder.

Immunosuppressive human anti-CD83 monoclonal antibody depletion of activated dendritic cells in transplantation

Current immunosuppressive/anti-inflammatory agents target the responding effector arm of the immune response and their nonspecific action increases the risk of infection and malignancy. These effects impact on their use in allogeneic haematopoietic cell transplantation and other forms of transplantation. Interventions that target activated dendritic cells (DCs) have the potential to suppress the induction of undesired immune responses (for example, graft versus host disease (GVHD) or transplant rejection) and to leave protective T-cell immune responses intact (for example, cytomegalovirus (CMV) immunity). We developed a human IgG1 monoclonal antibody (mAb), 3C12, specific for CD83, which is expressed on activated but not resting DC. The 3C12 mAb and an affinity improved version, 3C12C, depleted CD83(+) cells by CD16(+) NK cell-mediated antibody-dependent cellular cytotoxicity, and inhibited allogeneic T-cell proliferation in vitro. A single dose of 3C12C prevented human peripheral blood mononuclear cell-induced acute GVHD in SCID mouse recipients. The mAb 3C12C depleted CMRF-44(+)CD83(bright) activated DC but spared CD83(dim/-) DC in vivo. It reduced human T-cell activation in vivo and maintained the proportion of CD4(+) FoxP3(+) CD25(+) Treg cells and also viral-specific CD8(+) T cells. The anti-CD83 mAb, 3C12C, merits further evaluation as a new immunosuppressive agent in transplantation.

Tolerance of human fetal retinal pigment epithelium xenografts in monkey retina

BACKGROUND

RPE transplantation offers the possibility of treating certain forms of retinal degeneration. Understanding how to optimize the surgical technique for performing RPE transplantation, especially in primates, is therefore of considerable interest.

METHODS

Fifteen patch RPE transplants were performed in six monkeys. The transplant sites were examined at follow-up by ophthalmoscopy, biomicroscopy, fluorescein angiography and histology. Foveal and peripheral retinal transplants were compared.

RESULTS

Human fetal RPE xenografts can survive without rejection for at least 6 months after transplantation in monkey retina. Such grafts form a basal lamina and make intimate contacts with the outer segments of the host. Both rods and cones retain a normal appearance when in contact with unrejected transplants. Rejection occurred in only 30% (3/10) of the peripheral but in 60% (3/5) of the foveal transplants.

CONCLUSIONS

Cultured human fetal RPE patch transplants can survive and maintain local photoreceptor integrity for relatively long periods of time in monkey subretinal space without immunosuppression. Rejection, when it occurs, is more frequent near the fovea.

Ruthenium(II)-Catalyzed C-H Activation of Chromones with Maleimides to Synthesize Succinimide/Maleimide-Containing Chromones

An efficient route for the coupling of maleimides with chromones at the C5-position has been developed under Ru(II) catalysis. It could provide 1,4-addition products and oxidative Heck-type products by switching additives. Benzoic acid led to the formation of 1,4-addition products under solvent-free conditions, and silver acetate was promoted to the generation of oxidative Heck-type products. Various maleimides and chromones were suitable for this transformation, affording the desired products with good to excellent yields in a short reaction time. To understand the mechanism of this reaction, deuteration studies and control experiments have been performed.

Remodeling of glycoconjugates on CD44 enhances cell adhesion to hyaluronate, tumor growth and metastasis in B16 melanoma cells expressing beta1,4-N-acetylglucosaminyltransferase III

Beta1-4 N-acetylglucosaminyltransferase III (GnT-III) synthesizes bisecting N-acetylglucosamine structures on asparagine-linked oligosaccharides. Using B16-hm mouse melanoma cells stably expressing GnT-III activity as positive transfectants, the effect of bisecting N-acetylglucosamine on the function of CD44 was analyzed in association with adhesion to hyaluronate and tumor spread in mice. Transfection of GnT-III caused increased affinity of immunoprecipitated CD44 to erythro-agglutinating phytohemagglutinin, that preferentially recognizes bisecting N-acetylglucosamine, without affecting the surface CD44 amount, indicating an increase in bisecting N-acetylglucosamine residues on CD44 in positive transfectants. CD44-mediated adhesion to immobilized hyaluronate and the binding of fluorescence-labeled hyaluronate to the cell surface were increased in positive transfectants. The enhanced adhesion in positive transfectants was suppressed by the treatment with beta-N-acetylhexosaminidase, indicating that N-acetylglucosamine residues were responsible for the enhanced adhesion. Positive transfectants showed promoted CD44-mediated tumor growth and metastatic development in the spleen after subcutaneous inoculation into mice. These results indicate that glycosylation of CD44 due to GnT-III causes enhanced adhesion to hyaluronate, local tumor growth and metastatic growth in spleen, suggesting that the CD44-mediated adhesion and tumor spread can be modified through introduction of a glycosyltransferase gene.

Evaluation of water and electrolyte transport of tubular epithelial cells under osmotic and hydraulic pressure for development of bioartificial tubules

Our aim was to develop bioartificial tubules using tubular epithelial cells and artificial membranes and evaluate the function of water and electrolyte transport by various tubular epithelial cells. The cells were cultivated onto extracellular matrix (ProNectin F) coating polycarbonate membrane. Water transport from the apical to the basolateral site of cells was examined using a modified Ussing chamber module. Water transport under colloidal osmotic pressure on the apical site and hydraulic pressure on the basolateral site were higher in JTC-12, LLC-PK1 cells than in MDCK cells. Water transport under osmotic plus hydraulic pressure was highest in LLC-PK1 cells. We made bioartificial tubules using LLC-PK1 cells and polysulfone hollow fiber cartridges. Water and Na ion transport function was high, and BUN and creatinine passage was recognized in these bioartificial tubules. BUN and creatinine concentrations of reabsorption fluid in these bioartificial tubules were significantly lower than those concentrations of control media and of noncell attached polysulfone hollow fiber cartridges. Though LLC-PK1 cells were more preferable cells for the use of bioartificial tubules in terms of water and electrolyte transport, the passage of BUN and creatinine was not appropriate for clinical use. To select more preferable cells for bioartificial tubules which transport water and electrolytes and do not induce passage of uremic toxins is necessary.

Whole-exome sequencing for diagnosis of hereditary ichthyosis

BACKGROUND

Hereditary ichthyosis constitutes a diverse group of cornification disorders. Identification of the molecular cause facilitates optimal patient care.

OBJECTIVE

We wanted to estimate the diagnostic yield of applying whole-exome sequencing (WES) in the routine genetic workup of inherited ichthyosis.

METHODS

During a 3-year-period, all ichthyosis patients, except X-linked and mild vulgar ichthyosis, consecutively admitted to a university hospital clinic were offered WES with subsequent analysis of ichthyosis-related genes as a first-line genetic investigation. Clinical and molecular data have been collected retrospectively.

RESULTS

Genetic variants causative for the ichthyosis were identified in 27 of 34 investigated patients (79.4%). In all, 31 causative mutations across 13 genes were disclosed, including 12 novel variants. TGM1 was the most frequently mutated gene, accounting for 43.7% of patients suffering from autosomal recessive congenital ichthyosis (ARCI).

CONCLUSION

Whole-exome sequencing appears an effective tool in disclosing the molecular cause of patients with hereditary ichthyosis seen in clinical practice and should be considered a first-tier genetic test in these patients.

Release of platelet activating factor (PAF) and eicosanoids in UVC-irradiated corneal stromal cells

Ultraviolet (UV) irradiation provokes acute inflammation of the eye, and can be used to model processes that occur in response to damage to the anterior segment. This study characterized ultraviolet-C (UVC, 254 nm) irradiation-induced PAF synthesis, and arachidonic acid (20:4) and eicosanoid release in rabbit corneal stromal cells maintained in vitro. PAF was measured by radioimmunoassay (RIA) after exposing cultured corneal stromal cells to UVC irradiation (20 min, 2, 5, 10 mW/cm2). 14C-20:4-labeled stromal cells were also stimulated with UVC and radiolabeled phospholipids, neutral lipids and eicosanoids were measured. Synthesis of cell-associated and secreted PAF from corneal stromal cells was increased by UV irradiation. UV irradiation (254 nm, 5mW/cm2) enhanced 20:4 release from triacylglycerols, phosphatidylinositol, phosphatidylserine and phosphatidylethanolamine, and increased levels of 20:4-diacylglycerol and unesterified 20:4. The released 20:4 entered both the cyclooxygenase and lipoxygenase pathways after UVC irradiation. The PAF antagonist, BN52021 (10 microM) reduced UVC irradiation-induced stimulation of prostaglandin production, but failed to inhibit UVC-induced 20:4 release and synthesis of lipoxygenase products. Furthermore, exogenous PAF (1 microM) stimulated prostaglandin production, but did not increase the synthesis of lipoxygenase products from radiolabeled 20:4. The effects of PAF on prostaglandin synthesis were inhibited by BN52021. These findings indicate that responses to injury in cultured corneal stromal cells include PAF synthesis, release of 20:4 from glycerolipids, accumulation of diacylglycerol and synthesis of eicosanoids. The data further suggest that during UVC irradiation in vitro, PAF is not a primary or initial mediator of 20:4 release and synthesis of lipoxygenase products, but may mediate UVC-induced prostaglandin synthesis.

Patch culturing and transfer of human fetal retinal epithelium

Human retinal pigmented epithelium (RPE) can be cultured by removing small patches of this layer from the choroid of the fetal eye. Such RPE patches give rise to healthy, epithelioid monolayers in vitro within 1-2 weeks without contamination from retinal or choroidal cells. The viability and proliferative capacity of these cultures is independent of the initial polarity of the patch. These RPE monolayers develop apical/basal polarity and a basal lamina and rest on a field of collagen fibers; they are capable of phagocytizing outer segments. A patch can be lifted off a confluent monolayer and transferred to another culture dish without risking the viability of either the old or the new culture. This provides a means of transplanting an organized, polarized patch of human RPE from one place to another.

Wavelet transform as a bank of the matched filters

The wavelet transform is a powerful tool for the analysis of short transient signals. We detail the advantages of the wavelet transform over the Fourier transform and the windowed Fourier transform and consider the wavelet as a bank of the VanderLugt matched filters. This methodology is particularly useful in those cases in which the shape of the mother wavelet is approximately known a priori. A two-dimensional optical correlator with a bank of the wavelet filters is implemented to yield the time-frequency joint representation of the wavelet transform of one-dimensional signals.

Programmable optical phase-mostly holograms with coupled-mode modulation liquid-crystal television

Commercial twisted nematic liquid-crystal television provides coupled phase and amplitude modulation. We propose a simple wedged shear plate interferometer for in situ measurement of its phase modulation and operating curve. For a given operating curve, the coupled-mode modulation holograms are designed with an iterative method. We adjust the operating curve by rotating the polarizer and analyzer to obtain the optimal operating curve. The phase-mostly holograms yield good-quality reconstructed images with the zero-order spot reduced to a minimum. Experimental results are shown.

Use of FLAIR imaging to identify onset time of cerebral ischemia in a canine model

BACKGROUND AND PURPOSE

Stroke is a leading cause of death and disability, and many studies have focused on the evolution of FLAIR imaging in the acute and chronic time window. The purpose of this study was to evaluate the potential efficacy of FLAIR-related techniques in identifying the onset time of cerebral ischemia in a canine embolic stroke model.

MATERIALS AND METHODS

An embolic ischemic model was generated through the use of an autologous clot in 20 beagle dogs. Both FLAIR and DWI were performed at 3 hours, 4 hours, 5 hours, 6 hours, and 24 hours after embolization, respectively. Visual "DWI-FLAIR mismatch" was defined as hyperintense signal detected on DWI but not on FLAIR. The relative signal intensity of FLAIR-positive lesions and the degree of DWI-FLAIR mismatch was calculated as relative FLAIR = relative signal intensity of FLAIR positive lesions, mismatch degree = (100-VFLAIR/VDWI) × 100%.

RESULTS

The ischemic model was successfully established in all animals. FLAIR-positive lesions were seen in 3, 11, 16, 19, and 20 beagle dogs at 5 time points after embolization, respectively. There was significant correlation between the relative FLAIR, degree of DWI-FLAIR mismatch, and the onset time (relative FLAIR: r = +0.42; 95% CI, 0.20-0.60; mismatch degree: r = -0.85; 95% CI, 0.89-0.78). Receiver operating characteristic curves showed that the degree of DWI-FLAIR mismatch could identify the hyperacute ischemic lesions with a sensitivity range from 1.00-0.76; visual DWI-FLAIR mismatch sensitivity ranged from 0.85-0.39, whereas specificity was 0.83-0.95 versus 0.85-1.00.

CONCLUSIONS

The relative FLAIR and DWI-FLAIR mismatch values were useful in predicting the onset time in our canine embolic stroke model. The degree of DWI-FLAIR mismatch proposed in our study could be a good indicator with high sensitivity for identifying the hyperacute ischemic stroke.

Persistent response to pneumococcal vaccine in individuals supplemented with a novel water soluble extract of Uncaria tomentosa, C-Med-100

A human intervention study was carried out using male volunteers attending a General Practice Clinic in New York City involving comparison of individuals supplemented with 350 mg x 2 C-Med-100 daily dose for two months with untreated controls for their abilities to respond to a 23 valent pneumococcal vaccine. C-Med-100 is a novel nutraceutical extract from the South American plant Uncaria tomentosa or Cat's Claw which is known to possess immune enhancing and antiinflammatory properties in animals. There were no toxic side effects observed as judged by medical examination, clinical chemistry and blood cell analysis. However, statistically significant immune enhancement for the individuals on C-Med-100 supplement was observed by (i) an elevation in the lymphocyte/neutrophil ratios of peripheral blood and (ii) a reduced decay in the 12 serotype antibody titer responses to pneumococcal vaccination at 5 months.

Physiological and morphological responses of Tamarix ramosissima and Populus euphratica to altered groundwater availability

Riparian plants in arid areas are subject to frequent hydrological fluctuations induced through natural flow variation and water use by humans. Although many studies have focused on the success of Tamarix ramosissima Ledeb. in its invaded ranges, its major competitor in its home range, Populus euphratica Oliv., historically has dominated riparian forests where both species occur naturally. Thus, identifying ecophysiological differences between T. ramosissima and its co-evolved competitor under varying hydrological conditions may help us understand how flow regimes affect dominance in its home range and promote invasion in new ranges. We examined ecophysiological responses of T. ramosissima and P. euphratica, which are both native to the Tarim River Basin, northwest China, to experimental alterations in groundwater. Seedlings of both species were grown in lysimeters, first under well-watered conditions and then exposed to different groundwater treatments: inundation, drought, and relatively shallow, moderate and deep groundwater. Under inundation, T. ramosissima showed little growth whereas P. euphratica died after ~45 days. Droughted seedlings of both species suffered from considerable water stress evidenced by slow growth, decreased total leaf area and specific leaf area, and decreased xylem water potential (ψ), maximum photosynthetic rate and carboxylation efficiency. Both species had better ecophysiological performances under shallow and moderate groundwater conditions. When groundwater declined below rooting depth, seedlings of both species initially experienced decreased ψ, but ψ of T. ramosissima recovered late in the experiment whereas P. euphratica maintained decreased ψ. This ability of T. ramosissima to recover from water deficit might result from its rapid root elongation and subsequent ability to acquire groundwater, which in turn likely provides ecophysiological advantages over P. euphratica. Our results suggest that recent groundwater declines along the Tarim River could facilitate T. ramosissima more due to its rapid response to changed groundwater availability. This trait may also help the success of T. ramosissima as it invaded riparian ecosystems in southwestern USA.

In vivo tumor measurement of DNA damage, DNA repair and NAD pools as indicators of radiosensitization by metoclopramide

Metoclopramide (MCA), a N-substituted benzamide, causes DNA strand breaks and inhibits DNA repair in vitro and sensitizes radiation and chemotherapeutic drugs in human squamous cell carcinomas when xenographed into nude mice or in a rat glioma model. Here we report on the evaluation of the mechanism behind the radiosensitizing effects of MCA. DNA damage was measured in vivo in a CBA-mouse tumor line (A12B3, sarcoma tumor) by using both alkaline elution and nucleoid sedimentation analysis of cell suspensions prepared from either resected tumor, spleen tissues or whole blood samples. The amount of DNA damage caused by radiation alone, measured 30 min after the irradiation was started, was dose dependent up to 18 Gy in all tissues. The radiation-induced DNA damage in tumor tissue was elevated compared to radiation alone in the presence of MCA, but the level was not higher at 18 Gy compared to 6 Gy in the presence of MCA, and it was still not fully repaired 12 h after irradiation. HPLC analysis of the NAD pools in tumor tissue after DNA damage induction showed a delay in the recovery of the NAD pools (presumably due to the presence of still unrepaired DNA) after exposure to MCA (2 mg/kg) + radiation (6 Gy) compared to tumors exposed to radiation (6 Gy) only, which were fully restored after 48 h. These data confirm earlier published in vitro data on MCA as an inducer of DNA damage and an effector of DNA repair. In addition, the in vivo measurement of radiation-induced DNA damage and DNA repair using the nucleoid sedimentation and alkaline elution assays together with NAD pool determinations may prove to be effective intermediate endpoints in the evaluation of drugs as potential radiosensitizers.

DNA repair enhancement by a combined supplement of carotenoids, nicotinamide, and zinc

Four volunteers were involved for 5 weeks of a baseline period, followed by 7 weeks of a combined supplementation of nicotinamide, zinc, and carotenoids (Nicoplex). Blood sampling and bioassays were carried out every week during the evaluation period. The supplementation of Nicoplex resulted in statistically significant increased resistance to DNA single-strand breaks induced by H2O2 (DNA retained on filter % from 46.7 +/- 1.9 to 59.4 +/- 4.3; p < 0.01), increased DNA repair 60 min after induction of damage (DNA retained on filter % from 74.6 +/- 4.8 to 88.3 +/- 4.2; p < 0.01), elevated poly (ADP-ribose) polymerase (PARP) activity (p < 0.05), and an increased proliferative response to phytohemagglutinin (PHA) (p < 0.05) when compared with the levels before supplementation. However, when the same subjects were supplemented with nicotinamide, zinc, and carotenoids together with another 17 nutrients or minerals, there were no changes in DNA damage, DNA repair, or proliferative response to PHA. Through the use of a rat model, DNA repair of splenocytes 3 h after 12 Gy whole-body irradiation was significantly enhanced in rats supplemented with Nicoplex for 6 weeks (p < 0.05) and 8 weeks (p < 0.01). Comparison of Nicoplex and its components administered separately revealed that there was an additive effect on DNA repair for both single- and double-strand breaks (both p < 0.05). On the basis of the results, it is hypothesized that the enhanced effect of combined supplement of nicotinamide, zinc, and carotenoids on DNA repair depends on their diversified mechanisms of action while multinutrient supplementation may compromise the effects by inhibitory interactions including uptake and absorption.

Progress in identifying clinical relevance of inhibition, stimulation and measurements of poly ADP-ribosylation

Our laboratory, in collaboration with Oxigene Inc, has been involved in identifying commercially feasible clinical applications of measurement or modulation of ADP-ribosylation as a core technology. For this purpose a pivotal regulatory role for ADP-ribosylation in the repair of DNA lesions leading to cytotoxic as well as mutagenic events has been hypothesized. A new class of DNA repair inhibitors, the N-substituted benzamides, has been identified which can react with radiation to produce reactive intermediates that oxidize thiol amino acids. Their proposed mechanisms of action are two-fold: ie they can interact with radiation: i) to directly enhance DNA damage; and ii) to react with thiols in the zinc finger DNA binding domain of poly ADP-ribosyl transferase to inhibit DNA repair and thereby increase DNA damage. Sensamide, a clinically relevant formulation of metoclopramide which is an N-substituted benzamide, has indicated enhancement of tumor response and survival in patients with inoperable squamous cell carcinoma of the lung when it was administered as a radiosensitizer in a phase I/II trial and compared to historical controls. A mechanism of endogenous regulation of human mononuclear leucocyte ADP-ribosylation has been identified to be HOCl/N-chloramine production via the oxidative burst of phagocytes. HOCl/N-chloramines are potent oxidants of thiol-containing proteins. Quantitative estimation of N-chloramine sensitive plasma thiols has been identified as an effective surrogate measure of leucocyte poly ADPRT.(ABSTRACT TRUNCATED AT 250 WORDS)

A founder mutation p.H701P identified as a major cause of SPG7 in Norway

BACKGROUND AND PURPOSE

SPG7 is one of the most common forms of autosomal recessive hereditary spastic paraplegia. The phenotype has been shown to be heterogeneous, varying from a complex spastic ataxia to pure spastic paraplegia or pure ataxia. The aim of this study was to clinically and genetically characterize patients with SPG7 in Norway.

METHODS

Six Norwegian families with a clinical diagnosis of hereditary spastic paraplegia were diagnosed with SPG7 through Sanger sequencing and whole-exome sequencing. Haplotypes were established to identify a possible founder mutation. All patients were thoroughly examined and the clinical and molecular findings are described.

RESULTS

The core phenotype was spastic paraparesis with ataxia, bladder disturbances and progressive external ophthalmoplegia. The variant p.H701P was identified in homozygous state in one family and in compound heterozygous state in three families. Haplotype analysis of seven surrounding single nucleotide polymorphisms supports that this variant resides on a founder haplotype. Four of the families were compound heterozygous for the previously well-described p.A510V variant.

CONCLUSION

SPG7 is a common subgroup of hereditary spinocerebellar disorders in Norway. The broad phenotype in the Norwegian SPG7 population illustrates the challenges with the traditional dichotomous classification of hereditary spinocerebellar disorders into hereditary spastic paraplegia or hereditary ataxia. A Norwegian founder mutation p.H701P was identified in four out of six families, making it a major cause of SPG7 in Norway.

One-step construction of unsymmetrical thioureas and oxazolidinethiones from amines and carbon disulfide via a cascade reaction sequence

A versatile and efficient route for the preparation of unsymmetrical thioureas and oxazolidinethiones from amines and carbon disulfide has been achieved via a cascade reaction sequence.