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1.
HGG Adv ; 4(1): 100156, 2023 01 12.
Article in English | MEDLINE | ID: mdl-36386424

ABSTRACT

Phasing of heterozygous alleles is critical for interpretation of cis-effects of disease-relevant variation. We sequenced 477 individuals with cystic fibrosis (CF) using linked-read sequencing, which display an average phase block N50 of 4.39 Mb. We use these samples to construct a graph representation of CFTR haplotypes, demonstrating its utility for understanding complex CF alleles. These are visualized in a Web app, CFTbaRcodes, that enables interactive exploration of CFTR haplotypes present in this cohort. We perform fine-mapping and phasing of the chr7q35 trypsinogen locus associated with CF meconium ileus, an intestinal obstruction at birth associated with more severe CF outcomes and pancreatic disease. A 20-kb deletion polymorphism and a PRSS2 missense variant p.Thr8Ile (rs62473563) are shown to independently contribute to meconium ileus risk (p = 0.0028, p = 0.011, respectively) and are PRSS2 pancreas eQTLs (p = 9.5 × 10-7 and p = 1.4 × 10-4, respectively), suggesting the mechanism by which these polymorphisms contribute to CF. The phase information from linked reads provides a putative causal explanation for variation at a CF-relevant locus, which also has implications for the genetic basis of non-CF pancreatitis, to which this locus has been reported to contribute.


Subject(s)
Cystic Fibrosis , Intestinal Obstruction , Meconium Ileus , Infant, Newborn , Humans , Cystic Fibrosis/genetics , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Meconium Ileus/complications , Meconium , Intestinal Obstruction/complications , Trypsin , Trypsinogen/genetics
2.
NPJ Genom Med ; 7(1): 28, 2022 Apr 08.
Article in English | MEDLINE | ID: mdl-35396391

ABSTRACT

Over 400 variants in the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) are CF-causing. CFTR modulators target variants to improve lung function, but marked variability in response exists and current therapies do not address all CF-causing variants highlighting unmet needs. Alternative epithelial ion channel/transporters such as SLC26A9 could compensate for CFTR dysfunction, providing therapeutic targets that may benefit all individuals with CF. We investigate the relationship between rs7512462, a marker of SLC26A9 activity, and lung function pre- and post-treatment with CFTR modulators in Canadian and US CF cohorts, in the general population, and in those with chronic obstructive pulmonary disease (COPD). Rs7512462 CC genotype is associated with greater lung function in CF individuals with minimal function variants (for which there are currently no approved therapies; p = 0.008); and for gating (p = 0.033) and p.Phe508del/ p.Phe508del (p = 0.006) genotypes upon treatment with CFTR modulators. In parallel, human nasal epithelia with CC and p.Phe508del/p.Phe508del after Ussing chamber analysis of a combination of approved and experimental modulator treatments show greater CFTR function (p = 0.0022). Beyond CF, rs7512462 is associated with peak expiratory flow in a meta-analysis of the UK Biobank and Spirometa Consortium (p = 2.74 × 10-44) and provides p = 0.0891 in an analysis of COPD case-control status in the UK Biobank defined by spirometry. These findings support SLC26A9 as a therapeutic target to improve lung function for all people with CF and in individuals with other obstructive lung diseases.

4.
Genet Med ; 23(5): 927-933, 2021 05.
Article in English | MEDLINE | ID: mdl-33500570

ABSTRACT

PURPOSE: Cystic fibrosis (CF), caused by pathogenic variants in the CF transmembrane conductance regulator (CFTR), affects multiple organs including the exocrine pancreas, which is a causal contributor to cystic fibrosis-related diabetes (CFRD). Untreated CFRD causes increased CF-related mortality whereas early detection can improve outcomes. METHODS: Using genetic and easily accessible clinical measures available at birth, we constructed a CFRD prediction model using the Canadian CF Gene Modifier Study (CGS; n = 1,958) and validated it in the French CF Gene Modifier Study (FGMS; n = 1,003). We investigated genetic variants shown to associate with CF disease severity across multiple organs in genome-wide association studies. RESULTS: The strongest predictors included sex, CFTR severity score, and several genetic variants including one annotated to PRSS1, which encodes cationic trypsinogen. The final model defined in the CGS shows excellent agreement when validated on the FGMS, and the risk classifier shows slightly better performance at predicting CFRD risk later in life in both studies. CONCLUSION: We demonstrated clinical utility by comparing CFRD prevalence rates between the top 10% of individuals with the highest risk and the bottom 10% with the lowest risk. A web-based application was developed to provide practitioners with patient-specific CFRD risk to guide CFRD monitoring and treatment.


Subject(s)
Cystic Fibrosis , Diabetes Mellitus , Biomarkers , Canada , Cystic Fibrosis/complications , Cystic Fibrosis/diagnosis , Cystic Fibrosis/genetics , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Diabetes Mellitus/epidemiology , Diabetes Mellitus/genetics , Genome-Wide Association Study , Humans , Infant, Newborn
5.
Gene Ther ; 28(3-4): 142-154, 2021 04.
Article in English | MEDLINE | ID: mdl-32884151

ABSTRACT

Sandhoff disease (SD) is an autosomal recessive lysosomal storage disease caused by defects in the ß-subunit of ß-N-acetylhexosaminidase (Hex), the enzyme that catabolizes GM2 ganglioside. Hex deficiency causes neuronal storage of GM2 and related glycoconjugates, resulting in progressive neurodegeneration and death, typically in infancy. No effective treatment exists for human patients. Adeno-associated virus (AAV) gene therapy led to improved clinical outcome and survival of SD cats treated before the onset of disease symptoms. Most human patients are diagnosed after clinical disease onset, so it is imperative to test AAV-gene therapy in symptomatic SD cats to provide a realistic indication of therapeutic benefits that can be expected in humans. In this study, AAVrh8 vectors injected into the thalamus and deep cerebellar nuclei of symptomatic SD cats resulted in widespread central nervous system enzyme distribution, although a substantial burden of storage material remained. Cats treated in the early symptomatic phase showed delayed disease progression and a significant survival increase versus untreated cats. Treatment was less effective when administered later in the disease course, although therapeutic benefit was still possible. Results are encouraging for the treatment of human patients and provide support for the development AAV-gene therapy for human SD.


Subject(s)
Sandhoff Disease , Animals , Cats , Dependovirus/genetics , Disease Models, Animal , Genetic Therapy , Genetic Vectors/genetics , Humans , Sandhoff Disease/genetics , Sandhoff Disease/therapy , beta-N-Acetylhexosaminidases/genetics
6.
Mol Biotechnol ; 61(2): 73-83, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30448908

ABSTRACT

Overpopulation of free-roaming and wildlife animals negatively affects economy and public health in many parts of the world. Contraceptive vaccines are viewed as a valuable option for reducing numbers of unwanted animals. This study develops vaccines for potential use in animal contraception exploiting a DNA platform. Objectives of the study were to generate DNA constructs directed against gonadotropin-releasing hormone receptor (GnRHR), a crucial molecular player in animal reproduction, and characterize them for ability to promote immune responses and suppression of reproductive parameters in vivo. DNA constructs were created to encode for a recombinant protein composed of two domains: GnRHR, the target antigen, and ubiquitin (Ub), a support protein. Ub-GnRHR constructs administered intramuscularly or intradermally or containing different promoters were compared. CMV and EF1α promoters were shown to be superior to CAG. In fertility trials, mice immunized intradermally with Ub-GnRHR construct driven by EF1α had a significantly lower number of fetuses. Importantly, the impaired fertility was achieved with a single DNA immunization and without the use of adjuvants. The study demonstrated for the first time that targeting the GnRH receptor with DNA-based vaccines could be a viable option for animal contraception.


Subject(s)
Contraception/veterinary , Receptors, LHRH/genetics , Vaccines, Contraceptive/administration & dosage , Vaccines, DNA/administration & dosage , Animals , Antibodies/blood , CHO Cells , Cats , Cricetulus , Female , Fertility , Gene Expression , Immunization , Male , Mice , Promoter Regions, Genetic/genetics , Receptors, LHRH/immunology , Testosterone/blood , Ubiquitin/genetics
7.
Theriogenology ; 83(2): 266-75, 2015 Jan 15.
Article in English | MEDLINE | ID: mdl-25442384

ABSTRACT

GnRH receptors play vital roles in mammalian reproduction via regulation of gonadotropin secretion, which is essential for gametogenesis and production of gonadal steroids. GnRH receptors for more than 20 mammalian species have been sequenced, including human, mouse, and dog. This study reports the molecular cloning and sequencing of GnRH receptor (GnRHR) cDNA from the pituitary gland of the domestic cat, an important species in biomedical research. Feline GnRHR cDNA is composed of 981 nucleotides and encodes a 327 amino acid protein. Unlike the majority of mammalian species sequenced so far, but similar to canine GnRHR, feline GnRHR protein lacks asparagine in position three of the extracellular domain of the protein. At the amino acid level, feline GnRHR exhibits 95.1% identity with canine, 93.8% with human, and 88.9% with mouse GnRHR. Comparative sequence analysis of GnRHRs for multiple mammalian species led to resequencing of canine GnRHR, which differed from that previously published by a single base change that translates to a different amino acid in position 193. This single base change was confirmed in dogs of multiple breeds. Reverse transcriptase PCR analysis of GnRHR messenger RNA in different tissues from four normal cats indicated the presence of amplicons of varying lengths, including full-length as well as shortened GnRHR amplicons, pointing to the existence of truncated GnRHR transcripts in the domestic cat. This study is the first insight into molecular composition and expression of feline GnRHR and promotes better understanding of receptor organization, and distribution in various tissues of this species.


Subject(s)
Cats/genetics , Cloning, Molecular , Dogs/genetics , Receptors, LHRH/genetics , Sequence Analysis/veterinary , Amino Acid Sequence , Animals , Base Sequence , DNA, Complementary/chemistry , DNA, Complementary/genetics , Female , Humans , Male , Mice , Organ Specificity , Pituitary Gland/chemistry , RNA, Messenger/analysis , Receptors, LHRH/analysis , Receptors, LHRH/chemistry , Reverse Transcriptase Polymerase Chain Reaction/veterinary , Sequence Homology
8.
Sci Transl Med ; 6(231): 231ra48, 2014 Apr 09.
Article in English | MEDLINE | ID: mdl-24718858

ABSTRACT

Progressive debilitating neurological defects characterize feline G(M1) gangliosidosis, a lysosomal storage disease caused by deficiency of lysosomal ß-galactosidase. No effective therapy exists for affected children, who often die before age 5 years. An adeno-associated viral vector carrying the therapeutic gene was injected bilaterally into two brain targets (thalamus and deep cerebellar nuclei) of a feline model of G(M1) gangliosidosis. Gene therapy normalized ß-galactosidase activity and storage throughout the brain and spinal cord. The mean survival of 12 treated G(M1) animals was >38 months, compared to 8 months for untreated animals. Seven of the eight treated animals remaining alive demonstrated normalization of disease, with abrogation of many symptoms including gait deficits and postural imbalance. Sustained correction of the G(M1) gangliosidosis disease phenotype after limited intracranial targeting by gene therapy in a large animal model suggests that this approach may be useful for treating the human version of this lysosomal storage disorder.


Subject(s)
Brain/pathology , Genetic Therapy , Nervous System Diseases/therapy , Animals , Breeding , Cats , Dependovirus/metabolism , Disease Models, Animal , Disease Progression , Female , Humans , Lysosomes/enzymology , Magnetic Resonance Imaging , Male , Organ Specificity , Survival Analysis , beta-Galactosidase/genetics , beta-Galactosidase/therapeutic use
9.
Mol Ther ; 21(7): 1306-15, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23689599

ABSTRACT

Salutary responses to adeno-associated viral (AAV) gene therapy have been reported in the mouse model of Sandhoff disease (SD), a neurodegenerative lysosomal storage disease caused by deficiency of ß-N-acetylhexosaminidase (Hex). While untreated mice reach the humane endpoint by 4.1 months of age, mice treated by a single intracranial injection of vectors expressing human hexosaminidase may live a normal life span of 2 years. When treated with the same therapeutic vectors used in mice, two cats with SD lived to 7.0 and 8.2 months of age, compared with an untreated life span of 4.5 ± 0.5 months (n = 11). Because a pronounced humoral immune response to both the AAV1 vectors and human hexosaminidase was documented, feline cDNAs for the hexosaminidase α- and ß-subunits were cloned into AAVrh8 vectors. Cats treated with vectors expressing feline hexosaminidase produced enzymatic activity >75-fold normal at the brain injection site with little evidence of an immune infiltrate. Affected cats treated with feline-specific vectors by bilateral injection of the thalamus lived to 10.4 ± 3.7 months of age (n = 3), or 2.3 times as long as untreated cats. These studies support the therapeutic potential of AAV vectors for SD and underscore the importance of species-specific cDNAs for translational research.


Subject(s)
Cat Diseases/enzymology , Cat Diseases/therapy , Sandhoff Disease/enzymology , Sandhoff Disease/therapy , beta-N-Acetylhexosaminidases/metabolism , Animals , Cat Diseases/genetics , Cats , Dependovirus/genetics , Disease Models, Animal , Genetic Therapy/methods , Genetic Vectors/genetics , Sandhoff Disease/genetics , beta-N-Acetylhexosaminidases/genetics
10.
J Pastoral Care Counsel ; 67(3-4): 5, 2013.
Article in English | MEDLINE | ID: mdl-24720244

ABSTRACT

Mary Wollstonecraft Shelley's modern Prometheus shows us the eternal punishment of unrepaired shame--eternal entrapment within the shame triangle of victim, perpetrator and rescuer. This paper describes how Shelley's insight--that lack of love creates a monster living in shame--is being confirmed by neuroscience and how this is exemplified in two characters--the creature and Victor Frankenstein. Additionally, it delineates how pastoral counselors can help those suffering from unrepaired shame


Subject(s)
Clergy/methods , Helping Behavior , Professional-Patient Relations , Self Concept , Shame , Adaptation, Psychological , Disclosure , Female , Humans , Male , Medicine in Literature
11.
PLoS One ; 7(4): e36077, 2012.
Article in English | MEDLINE | ID: mdl-22563440

ABSTRACT

BACKGROUND: Many patients with cystic fibrosis develop persistent airway infection/colonization with Aspergillus fumigatus, however the impact of A. fumigatus on clinical outcomes remains unclear. The objective of this study was to determine whether treatment directed against Aspergillus fumigatus improves pulmonary function and clinical outcomes in patients with cystic fibrosis (CF). METHODS: We performed a double-blind randomized placebo-controlled pilot clinical trial involving 35 patients with CF whose sputum cultures were chronically positive for A. fumigatus. Participants were centrally randomized to receive either oral itraconazole 5 mg/kg/d (N = 18) or placebo (N = 17) for 24 weeks. The primary outcome was the proportion of patients who experienced a respiratory exacerbation requiring intravenous antibiotics over the 24 week treatment period. Secondary outcomes included changes in FEV(1) and quality of life. RESULTS: Over the 24 week treatment period, 4 of 18 (22%) patients randomized to itraconazole experienced a respiratory exacerbation requiring intravenous antibiotics, compared to 5 of 16 (31%) placebo treated patients, P = 0.70. FEV(1) declined by 4.62% over 24 weeks in the patients randomized to itraconazole, compared to a 0.32% improvement in the placebo group (between group difference = -4.94%, 95% CI: -15.33 to 5.45, P = 0.34). Quality of life did not differ between the 2 treatment groups throughout the study. Therapeutic itraconazole blood levels were not achieved in 43% of patients randomized to itraconazole. CONCLUSION: We did not identify clinical benefit from itraconazole treatment for CF patients whose sputum was chronically colonized with A. fumigatus. Limitations of this pilot study were its small sample size, and failure to achieve therapeutic levels of itraconazole in many patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT00528190.


Subject(s)
Aspergillus fumigatus/pathogenicity , Cystic Fibrosis/drug therapy , Administration, Oral , Adolescent , Adult , Antifungal Agents/therapeutic use , Aspergillosis/complications , Aspergillosis/drug therapy , Child , Cystic Fibrosis/complications , Cystic Fibrosis/physiopathology , Double-Blind Method , Female , Forced Expiratory Volume , Hospitalization , Humans , Injections, Intravenous , Itraconazole/therapeutic use , Lung/physiopathology , Male , Pilot Projects , Placebo Effect , Quality of Life , Respiratory Function Tests , Sputum/microbiology , Time Factors , Young Adult
12.
J Spinal Cord Med ; 32(4): 398-403, 2009.
Article in English | MEDLINE | ID: mdl-19777860

ABSTRACT

BACKGROUND: Some people with chronic spinal cord injury (SCI) have low vitamin D levels and secondary hyperparathyroidism. OBJECTIVE: To determine whether, and to what extent, an acute calcium infusion decreased levels of N-telopeptide (NTx), a marker of osteoclastic activity, in individuals with chronic SCI. STUDY DESIGN: Case series. SUBJECTS: Eight men with chronic SCI. A relatively low serum 25 hydroxyvitamin D concentration (25[OH]D < or =20 ng/mL) and/or a high parathyroid hormone (PTH) (>55 pg/mL) was a prerequisite for study inclusion. METHODS: Calcium gluconate bolus 0.025 mmol elemental calcium/kg over 20 minutes followed by a constant infusion of 0.025 mmol/kg per hour for 6 hours was infused; blood samples were collected every 2 hours for measurement of serum total calcium, creatinine, NTx, and PTH. RESULTS: All results are expressed as means (+/- SDs). Baseline serum 25-hydroxyvitamin D level was 14.5 +/- 3.5 ng/mL (range: 10.2-19.6 ng/mL); PTH, 70 +/- 25 pg/mL (range: 37-100 pg/mL); and NTx, 21 +/- 7 nM bone collagen equivalents (BCE) (range: 14-34 nM). At 2, 4, and 6 hours after the calcium infusion, serum calcium rose from 9.3 +/- 0.2 to 10.8 +/- 0.9, 10.5 +/- 0.8, and 10.6 +/- 0.6 mg/d; PTH was suppressed from 70 +/- 25 pg/mL to 18 +/- 12, 16 +/- 9, and 15 +/- 9 pg/mL, respectively; NTx fell from 21 +/- 8 nM BCE to 17 +/- 5, 12 +/- 4, and 12 +/- 3 nM BCE, respectively. CONCLUSIONS: Serum NTx is a marker for bone collagen catabolism, and its reduction suggests that bone turnover was decreased. A relative deficiency of vitamin D associated with chronically elevated levels of PTH would be expected to increase bone turnover and to worsen the bone loss associated with immobilization.


Subject(s)
Organometallic Compounds/administration & dosage , Spinal Cord Injuries/blood , Spinal Cord Injuries/drug therapy , Trisaccharides/administration & dosage , Adult , Analysis of Variance , Calcium/blood , Collagen Type I/blood , Humans , Male , Parathyroid Hormone/blood , Peptides/blood , Time Factors , Vitamin D/analogs & derivatives , Vitamin D/blood , Young Adult
13.
Am J Respir Crit Care Med ; 180(8): 761-8, 2009 Oct 15.
Article in English | MEDLINE | ID: mdl-19590021

ABSTRACT

RATIONALE: We developed an evidence-based decision aid for patients with advanced cystic fibrosis considering referral for lung transplantation. OBJECTIVES: To prospectively evaluate whether use of the decision aid increased knowledge about the options, improved realistic expectations, and decreased decisional conflict in adult patients. METHODS: We performed a single-blind randomized controlled trial involving 149 adult patients with cystic fibrosis with an FEV(1)

Subject(s)
Cystic Fibrosis/surgery , Decision Making, Computer-Assisted , Health Knowledge, Attitudes, Practice , Lung Transplantation/psychology , Patient Participation , Adult , Cystic Fibrosis/psychology , Decision Support Techniques , Female , Humans , Male , Patient Education as Topic , Young Adult
14.
J Marital Fam Ther ; 35(3): 350-68, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19522787

ABSTRACT

The article describes a research study that explored the process of how change occurred for one distressed couple and a specific therapist in a naturalistic setting. Quantitative and qualitative data were collected on the couple at multiple points in the therapy. A research team comprised of five members met regularly to analyze the data and collectively they arrived at a theory of change for the couple posttherapy. Conclusions are made related to how change occurred for the couple with an emphasis on the role of extratherapeutic events, client motivational factors, the therapeutic alliance, hope and expectancy factors, therapist factors, specific techniques and interventions, and other surprise factors that contributed to change.


Subject(s)
Marital Therapy/methods , Adaptation, Psychological , Defense Mechanisms , Education, Graduate , Emotions , Family Conflict/psychology , Female , Follow-Up Studies , Humans , Male , Marital Therapy/education , Motivation , Poverty/psychology , Professional-Patient Relations , Set, Psychology
15.
Mol Genet Metab ; 97(1): 53-9, 2009 May.
Article in English | MEDLINE | ID: mdl-19231264

ABSTRACT

GM2 gangliosidosis is a fatal, progressive neuronopathic lysosomal storage disease resulting from a deficiency of beta-N-acetylhexosaminidase (EC 3.2.1.52) activity. GM2 gangliosidosis occurs with varying degrees of severity in humans and in a variety of animals, including cats. In the current research, European Burmese cats presented with clinical neurological signs and histopathological features typical of a lysosomal storage disease. Thin layer chromatography revealed substantial storage of GM2 ganglioside in brain tissue of affected cats, and assays with a synthetic fluorogenic substrate confirmed the absence of hexosaminidase activity. When the hexosaminidase beta-subunit cDNA was sequenced from affected cats, a 91 base pair deletion constituting the entirety of exon 12 was documented. Subsequent sequencing of introns 11 and 12 revealed a 15 base pair deletion at the 3' end of intron 11 that included the preferred splice acceptor site, generating two minor transcripts from cryptic splice acceptor sites in affected Burmese cats. In the cerebral cortex of affected cats, hexosaminidase beta-subunit mRNA levels were approximately 1.5 times higher than normal (P<0.001), while beta-subunit protein levels were substantially reduced on Western blots.


Subject(s)
Cat Diseases/enzymology , Lysosomal Storage Diseases/veterinary , Nerve Degeneration/complications , Nerve Degeneration/enzymology , beta-Hexosaminidase beta Chain/metabolism , Animals , Base Sequence , Blotting, Western , Cats , Cerebral Cortex/enzymology , Cerebral Cortex/pathology , Chromatography, Thin Layer , DNA Mutational Analysis , Europe , Gangliosidoses, GM2/enzymology , Gangliosidoses, GM2/pathology , Lipids/analysis , Lysosomal Storage Diseases/complications , Lysosomal Storage Diseases/enzymology , Molecular Sequence Data , Myanmar
16.
Metab Brain Dis ; 23(2): 161-73, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18421424

ABSTRACT

Lysosomal beta-galactosidase is required for the degradation of GM1 ganglioside and other glycolipids and glycoproteins with a terminal galactose moiety. Deficiency of this enzyme leads to the lysosomal storage disorder, GM1 gangliosidosis, marked by severe neurodegeneration resulting in premature death. As a step towards preclinical studies for enzyme replacement therapy in an animal model of GM1 gangliosidosis, a feline beta-galactosidase cDNA was cloned into a mammalian expression vector and subsequently expressed in Chinese hamster ovary (CHO-K1) cells. The enzyme secreted into culture medium exhibited specific activity on two synthetic substrates as well as on the native beta-galactosidase substrate, GM1 ganglioside. The enzyme was purified from transfected CHO-K1 cell culture medium by chromatography on PATG-agarose. The affinity-purified enzyme preparation consisted mainly of the protein with approximate molecular weight of 94 kDa and displayed immunoreactivity with antibodies raised against a 16-mer synthetic peptide corresponding to C-terminal amino acid sequence deduced from the feline beta-galactosidase cDNA.


Subject(s)
G(M1) Ganglioside/biosynthesis , Gangliosidosis, GM1/enzymology , Genetic Therapy/methods , Recombinant Proteins/isolation & purification , beta-Galactosidase/isolation & purification , Animals , Antibody Specificity/immunology , CHO Cells , Cats , Chromatography, Agarose , Cloning, Molecular/methods , Cricetinae , Cricetulus , Culture Media, Conditioned/chemistry , DNA, Complementary/genetics , Disease Models, Animal , G(M1) Ganglioside/genetics , Gangliosidosis, GM1/genetics , Gangliosidosis, GM1/therapy , Genetic Vectors/genetics , Molecular Weight , Protein Structure, Tertiary/physiology , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Transfection/methods , beta-Galactosidase/genetics , beta-Galactosidase/metabolism
17.
J Clin Pharmacol ; 46(4): 476-82, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16554457

ABSTRACT

Patients with chronic spinal cord injury (SCI), a condition associated with reduced physical function, have been reported to have lower plasma insulin-like growth factor-I (IGF-I) levels than able-bodied persons. We evaluated the potential for daily low-dose baclofen administered over several weeks to increase plasma IGF-I levels. Ten healthy male outpatients with chronic SCI were studied prospectively. Patients received escalating doses of baclofen for 4 weeks at each dose level (5, 10, and 20 mg/d). At each dose of baclofen, an increase in the plasma IGF-I was noted; significant increases in plasma IGF-I occurred at 2 weeks after administration of drug at doses of 10 and 20 mg/d, with a subsequent rise to peak levels on baclofen 20 mg/d [baseline, 205+/-74; peak, 218+/-76 (not significant), 239+/-83 (P<.05), 263+/-87 microg/L (P<.05), at baclofen 5, 10, and 20 mg/d, respectively]. In conclusion, low-dose baclofen administration for 4 weeks stimulated the growth hormone-IGF-I axis in persons with SCI, with the potential for beneficial effects on body composition.


Subject(s)
Baclofen/administration & dosage , Baclofen/pharmacology , Insulin-Like Growth Factor I/metabolism , Muscle Relaxants, Central/administration & dosage , Muscle Relaxants, Central/pharmacology , Spinal Cord Injuries/drug therapy , Adult , Baclofen/therapeutic use , Chronic Disease , Dose-Response Relationship, Drug , Humans , Male , Middle Aged , Muscle Relaxants, Central/therapeutic use , Paraplegia/drug therapy , Quadriplegia/drug therapy
18.
Acta Neuropathol ; 110(5): 443-50, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16200419

ABSTRACT

The G(M2) activator protein is required for successful degradation of G(M2) ganglioside by the A isozyme of lysosomal beta-N-acetylhexosaminidase (EC 3.2.1.52). Deficiency of the G(M2) activator protein leads to a relentlessly progressive accumulation of G(M2) ganglioside in neuronal lysosomes and subsequent fatal deterioration of central nervous system function. G(M2) activator deficiency has been described in humans, dogs and mice. This manuscript reports the discovery and characterization of a feline model of G(M2) activator deficiency that exhibits many disease traits typical of the disorder in other species. Cats deficient in the G(M2) activator protein develop clinical signs at approximately 14 months of age, including motor incoordination and exaggerated startle response to sharp sounds. Affected cats exhibit central nervous system abnormalities such as swollen neurons, membranous cytoplasmic bodies, increased sialic acid content and elevated levels of G(M2) ganglioside. As is typical of G(M2) activator deficiency, hexosaminidase A activity in tissue homogenates appears normal when assayed with a commonly used synthetic substrate. When the G(M2) activator cDNA was sequenced from normal and affected cats, a deletion of 4 base pairs was identified as the causative mutation, resulting in alteration of 21 amino acids at the C terminus of the G(M2) activator protein.


Subject(s)
Cats , Disease Models, Animal , G(M2) Activator Protein/genetics , Gangliosidoses, GM2/genetics , Mutation/genetics , Aging , Amino Acid Sequence , Animals , Base Sequence , Brain Chemistry , Central Nervous System/pathology , Central Nervous System/physiopathology , DNA, Complementary/analysis , DNA, Complementary/genetics , Female , G(M2) Activator Protein/chemistry , G(M2) Activator Protein/deficiency , G(M2) Activator Protein/physiology , G(M2) Ganglioside/analysis , G(M2) Ganglioside/metabolism , Gangliosidoses, GM2/metabolism , Gene Deletion , Hexosaminidases/analysis , Liver/enzymology , Male , Molecular Sequence Data , N-Acetylneuraminic Acid/analysis , Neurons/chemistry , Neurons/pathology , Pedigree , Thymus Gland/enzymology
19.
J Rehabil Res Dev ; 42(3): 305-13, 2005.
Article in English | MEDLINE | ID: mdl-16187243

ABSTRACT

Eleven subjects participated in a prospective placebo-controlled trial to address the efficacy of pamidronate in reducing bone loss in persons with acute spinal cord injury (SCI). We administered pamidronate (treatment) or normal saline (placebo) intravenously at baseline (22 to 65 days after injury) and sequentially over 12 months, with follow-up at 18 and 24 months. Regional bone mineral density (BMD) was lost over time, regardless of group. In the treatment group compared with the placebo group, we noted a mild early reduction in loss of total leg BMD. Significant bone loss from baseline occurred earlier in the placebo group at the regional sites than in the treatment group. However, by the end of the treatment and follow-up phases, both groups demonstrated a similar percent bone loss from baseline. Despite an early reduction in bone loss, pamidronate failed to prevent major, long-term bone loss in persons with acute neurologically complete SCI.


Subject(s)
Bone Density Conservation Agents/pharmacology , Bone Density/drug effects , Bones of Lower Extremity/drug effects , Diphosphonates/pharmacology , Osteoporosis/prevention & control , Spinal Cord Injuries/complications , Acute Disease , Adult , Biomarkers/blood , Biomarkers/urine , Bone Density Conservation Agents/therapeutic use , Calcium/blood , Calcium/urine , Collagen/urine , Diphosphonates/therapeutic use , Double-Blind Method , Drug Administration Schedule , Female , Humans , Immobilization/adverse effects , Infusions, Intravenous , Male , Middle Aged , Osteoporosis/etiology , Pamidronate , Paraplegia/complications , Prospective Studies , Quadriplegia/complications
20.
J Spinal Cord Med ; 28(3): 203-7, 2005.
Article in English | MEDLINE | ID: mdl-16048137

ABSTRACT

BACKGROUND/OBJECTIVE: An increased prevalence of vitamin D deficiency has been reported in persons with chronic spinal cord injury (SCI), but treatment guidelines for replacement are not available. The purpose of this study was to evaluate two types of vitamin D therapy on calcium metabolism and vitamin D status in persons with SCI. METHODS: Ten subjects with chronic SCI who were vitamin D deficient received 25 hydroxyvitamin D3 [25(OH)D], 50 microg twice a week, for 14 days (Study 1). Regardless of vitamin D status, 40 subjects received vitamin D3 800 IU (20 microg) daily for 12 months (Study 2). Supplemental calcium was administered. The response to therapy was determined by the effect upon serum 25(OH)D levels. Results are expressed as mean +/- standard deviation. RESULTS: In Study 1, serum 25(OH)D levels increased by day 14 (8.7 +/- 2.1 vs 14.7 +/- 3.6 ng/mL; P < 0.0005). However, in 8 of 10 subjects, 25(OH)D levels were still below the absolute lower limit of normal. Serum calcium levels were not significantly different, but urinary calcium excretion increased (103 +/- 81 vs 184 +/- 145 mg/d; P < 0.01). Serum parathyroid hormone (PTH) levels decreased (35 +/- 26 vs 1 7 +/- 12 pg/ mL; P < 0.01). In Study 2, after 12 months of vitamin D supplementation, 9 subjects had an absolute and 23 had a relative vitamin D deficiency, compared with 33 and 6 subjects, respectively, at baseline. By 12 months, the 25(OH)D level increased (10.7 +/- 7.1 to 22.5 +/- 7.5 ng/mL; P < 0.0001) and the serum PTH level decreased (37 +/- 16 vs 25 +/- 11 pg/mL; P < 0.0001). CONCLUSIONS: Although 25(OH)D levels significantly increased in both studies, the replacement therapies employed were not sufficient to recommend for adoption for clinical use, indicating the need for higher doses and/or for longer periods of administration.


Subject(s)
Calcifediol/therapeutic use , Spinal Cord Injuries/complications , Vitamin D Deficiency/complications , Vitamin D Deficiency/drug therapy , Adult , Aged , Calcifediol/blood , Calcium/blood , Calcium/therapeutic use , Calcium/urine , Humans , Middle Aged , Parathyroid Hormone/blood , Spinal Cord Injuries/blood , Spinal Cord Injuries/drug therapy , Spinal Cord Injuries/urine , Treatment Failure , Vitamin D Deficiency/blood
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