Difference in the nature of tannins on in vitro ruminal methane and volatile fatty acid production and on methanogenic archaea and protozoal populations

Six plant sources of hydrolyzable tannins (HT) or HT and condensed tannins (CT; designated as HT1, HT2, HT3, HT + CT1, HT + CT2, and HT + CT3) were evaluated to determine their effects in vitro on CH(4) production and on ruminal archaeal and protozoa populations, and to assess potential differences in biological activities between sources containing HT only or HT and CT. Samples HT1, HT2, and HT3 contained only HT, whereas samples HT + CT1, HT + CT2, and HT + CT3 contained HT and CT. In experiment 1, in vitro incubations with samples containing HT or HT + CT resulted in a decrease in CH(4) production of 0.6 and 5.5%, respectively, compared with that produced by incubations containing the added tannin binder polyethylene glycol-6000. Tannin also suppressed the population of methanogenic archaea in all incubations except those with HT2, with an average decrease of 11.6% in HT incubations (15.8, 7.09, and 12.0 in HT1, HT2, and HT3) and 28.6% in incubations containing HT + CT (35.0, 40.1, and 10.8 in HT + CT1, HT + CT2, and HT + CT3) when compared with incubations containing added polyethylene glycol-6000. The mean decrease in protozoal counts was 12.3% in HT and 36.2% in HT + CT incubations. Tannins increased in vitro pH, reduced total VFA concentrations, increased propionate concentrations, and decreased concentrations of iso-acids. In experiment 2, when a basal diet was incubated with graded levels of HT + CT1, HT + CT2, and HT + CT3, the total gas and CH4 production and archaeal and protozoal populations decreased as the concentration of tannins increased. Our results confirm that tannins suppress methanogenesis by reducing methanogenic populations in the rumen either directly or by reducing the protozoal population, thereby reducing methanogens symbiotically associated with the protozoal population. In addition, tannin sources containing both HT and CT were more potent in suppressing methanogenesis than those containing only HT.

Emerinopathy and laminopathy clinical, pathological and molecular features of muscular dystrophy with nuclear envelopathy in Japan

Mutations in the genes for nuclear envelope proteins of emerin (EMD) and lamin A/C (LMNA) are known to cause Emery-Dreifuss muscular dystrophy (EDMD) and limb girdle muscular dystrophy (LGMD). We compared clinical features of the muscular dystrophy patients associated with mutations in EMD (emerinopathy) and LMNA (laminopathy) in our series. The incidence of laminopathy was slightly higher than that of emerinopathy. The age at onset of the disease in emerinopathy was variable and significantly older than in laminopathy. The initial symptom of emerinopathy was also variable, whereas nearly all laminopathy patients presented initially with muscle weakness. Calf hypertrophy was often seen in laminopathy, underscoring the importance of mutation screening for LMNA in childhood muscular dystrophy with calf hypertrophy. The clinical spectrum of emerinopathy is actually wider than previously known including EDMD, LGMD, conduction defects with minimal muscle/joint involvement, and their intermittent forms. Pathologically, no marked difference was observed between emerinopathy and laminopathy. Increased number and variation in size of myonuclei were detected. More precise observations using electron microscopy is warranted to characterize the detailed nuclear changes in nuclear envelopathy.

Patterns of dystrophin gene deletion in Egyptian Duchenne/Becker muscular dystrophy patients

Large variations in the proportion of intragenic deletion in the dystrophin gene have been observed in different populations. Although dystrophin gene deletion was extensively studied all over the world, only few studies were done on Egyptian population and there was no account on the dystrophin gene duplication. In this study, we present our results on the pattern of deletion of the dystrophin gene together with the usage of quantitative polymerase chain reaction (PCR) as a method for duplication analysis within the dystrophin gene in Egyptian patients. Forty one Duchene/Becker muscular dystrophy patients were included in this study. The diagnosis was based on detailed clinical assessment, serum creatine kinase (CK) level, neurophysiologic study and muscle biopsy for histopathological analysis. DNA was extracted from ten milliliter peripheral blood according to basic protocol, and multiplex polymerase chain reaction for dystrophin gene using both Chamberlin and Beggs sets of primers amplifying eighteen exons covering the two main dystrophin gene hot spots. In addition primers from Abbs set were used when it was necessary to check the exon borders. DNA from cases with no detectable deletion was analyzed for dystrophin gene duplication using quantitative PCR technique. We had a percentage of 61.1% deletion which is higher than data from previous Egyptian studies and most of the deletion was localized in the major hotspot region between exons 44 and 52 and we had 5% of the cases with duplication. Our results were compared with previous studies from Egypt and with studies from different populations especially with data recorded in the Middle East and North Africa.

Primary collagen VI deficiency is the second most common congenital muscular dystrophy in Japan

OBJECTIVES

To determine the frequency of primary collagen VI deficiency in congenital muscular dystrophy (CMD) in Japan and to establish the genotype-phenotype correlation.

METHODS

We performed immunohistochemistry for collagen VI in muscles from 362 Japanese patients with CMD, and directly sequenced the three collagen VI genes, COL6A1, COL6A2, and COL6A3, in patients found to have collagen VI deficiency.

RESULTS

In Japan, primary collagen VI deficiency accounts for 7.2% of congenital muscular deficiency. Among these patients, five had complete deficiency (CD) and 29 had sarcolemma-specific collagen VI deficiency (SSCD). We found two homozygous and three compound heterozygous mutations in COL6A2 and COL6A3 in all five patients with CD, and identified heterozygous missense mutations or in-frame small deletions in 21 patients with SSCD in the triple helical domain (THD) of COL6A1, COL6A2, and COL6A3. All mutations in SSCD were sporadic dominant. No genotype-phenotype correlation was seen.

CONCLUSION

Primary collagen VI deficiency is the second most common CMD after Fukuyama type CMD in Japan. Dominant mutations located in the N-terminal side from the cysteine residue in the THD of COL6A1, COL6A2, and COL6A3 are closely associated with SSCD.

Reduced cell anchorage may cause sarcolemma-specific collagen VI deficiency in Ullrich disease

BACKGROUND

COL6 gene mutations are associated with Ullrich congenital muscular dystrophy (UCMD), which is clinically characterized by muscle weakness from early infancy, hyperlaxity of distal joints, and multiple proximal joint contractures. We previously reported that the majority of patients with UCMD have sarcolemma-specific collagen VI deficiency (SSCD). More recently, we found heterozygous COL6A1 glycine substitutions in patients with UCMD with SSCD.

OBJECTIVE

To elucidate how COL6A1 glycine mutation leads to SSCD.

METHODS

We evaluated the synthesis, formation, and binding of collagen VI to the extracellular matrix in fibroblasts with p.G284R mutation in COL6A1.

RESULTS

Collagen VI was normally secreted into the cultured medium in fibroblasts harboring p.G284R mutation. When the medium with normal collagen VI was added to collagen VI-deficient fibroblast culture, collagen VI bound surrounding the cells, while collagen VI with p.G284R mutation did not. Cell adhesion of fibroblasts with p.G284R mutation was markedly reduced similarly to that of collagen VI-deficient cells. Interestingly, this reduction in adhesion of the cells with p.G284R mutation was recovered by the addition of the medium with normal collagen VI, which would suggest a therapeutic strategy for a replacement therapy.

CONCLUSION

Heterozygous glycine substitution in COL6A1 may cause decreased binding of collagen VI microfibrils to the extracellular matrix resulting in sarcolemma-specific collagen VI deficiency.

Congenital neuromuscular disease with uniform type 1 fiber and RYR1 mutation

BACKGROUND

Congenital neuromuscular disease with uniform type 1 fiber (CNMDU1) is a rare form of congenital myopathy, which is pathologically diagnosed by the presence of more than 99% of type 1 fiber, with no specific structural changes. Its pathogenic mechanism is still unknown. We recently reported that almost all patients with central core disease (CCD) with ryanodine receptor 1 gene (RYR1) mutations in the C-terminal domain had type 1 fibers, nearly exclusively, in addition to typical central cores.

OBJECTIVE

To investigate whether CNMDU1 is associated with RYR1 mutation.

METHODS

We studied 10 unrelated Japanese patients who were diagnosed to have CNMDU1 based on clinical features and muscle pathology showing more than 99% type 1 muscle fibers. We extracted genomic DNA from frozen muscles and directly sequenced all 106 exons and their flanking intron-exon boundaries of RYR1.

RESULTS

Four of 10 patients had a heterozygous mutation, three missense and one deletion, all in the C-terminal domain of RYR1. Two missense mutations were previously reported in CCD patients. Clinically, patients with mutations in RYR1 showed milder phenotype compared with those without mutations.

CONCLUSION

Congenital neuromuscular disease with uniform type 1 fiber (CNMDU1) in 40% of patients is associated with mutations in the C-terminal domain of RYR1, suggesting that CNMDU1 is allelic to central core disease at least in some patients.

Influence of high temperature and humidity on rumen bacterial diversity in Holstein heifers

The effect of heat and humidity stresses on the rumen bacterial molecular diversity of heifers was studied. No statistically significant changes in the rumen microbiota composition were found in the first experiment (average body mass 250kg) while in the second and third experiments (additional variables included the relative humidity and body weight), the microbiota composition was significantly different at elevated environmental temperatures and humidity. These shifts were accompanied by the decrease in concentration of short-chain fatty acids in the rumen.

Y-chromosomal binary haplogroups in the Japanese population and their relationship to 16 Y-STR polymorphisms

We investigated Y chromosomal binary and STR polymorphisms in 263 unrelated male individuals from the Japanese population and further examined the relationships between the two separate types of data. Using 47 biallelic markers we distinguished 20 haplogroups, four of which (D2b1/-022457, O3/-002611*, O3/-LINE1 del, and O3/-021354*) were newly defined in this study. Most haplogroups in the Japanese population are found in one of the three major clades, C, D, or O. Among these, two major lineages, D2b and O2b, account for 66% of Japanese Y chromosomes. Haplotype diversity of binary markers was calculated at 86.3%. The addition of 16 Y-STR markers increased the number of haplotypes to 225, yielding a haplotype diversity of 99.40%. A comparison of binary haplogroups and Y-STR type revealed a close association between certain binary haplogroups and Y-STR allelic or conformational differences, such as those at the DXYS156Y, DYS390m, DYS392, DYS437, DYS438 and DYS388 loci. Based on our data on the relationships between binary and STR polymorphisms, we estimated the binary haplogroups of individuals from STR haplotypes and frequencies of binary haplogroups in other Japanese, Korean and Taiwanese Han populations. The present data will enable researchers to connect data from binary haplogrouping in anthropological studies and Y-STR typing in forensic studies in East Asian populations, especially those in and around Japan.

Developmental changes in the kinetics of glucose and urea in Holstein calves

Because weaning is the point when the nutrient composition of feed changes for the neonatal ruminant, the present experiment was conducted to assess the developmental changes in the kinetics of glucose and urea over this period, using stable isotopes of glucose and urea, at 4, 13, and 24 wk in calves. Plasma concentrations of nonesterified fatty acids, amino-N, urea-N, and insulin-like growth factor-I increased, but that of growth hormone decreased with age. The plasma glucose concentration increased at 13 wk of age and thereafter decreased at 24 wk of age. The glucose irreversible loss and recycling rates were significantly higher at 4 wk of age than at 13 and 24 wk of age. On the other hand, the irreversible loss and recycling rates of urea, as well as the urea pool size, were higher at 24 wk of age than at 4 and 13 wk. It is concluded that weaning at 6 wk is the pivotal time for the alteration of glucose kinetics. However, the aging process, but not weaning, is important for changes in the kinetics of urea in calves.

Sarcolemmopathy: muscular dystrophies with cell membrane defects

In this article, we review the molecular pathology of muscular dystrophies caused by defects of proteins located within or near cell membranes. These disorders include Bethlem myopathy, merosinopathy, dystrophinopathy, sarcoglycanopathies, integrinopathy, dysferlinopathy and caveolinopathy. We refer to these diseases collectively as sarcolemmopathy. Here, we describe the biological functions of these proteins in the context of muscular contractions and their roles in the infrastructure of muscle; defects of muscle infrastructures cause those diseases. As an example, in dystrophinopathy, cell membranes have mechanical defects due to the absence of dystrophin. Cracks of the cell membrane induced by muscle contraction may allow the influx and efflux of substances that trigger muscle cell degeneration. However, such cracks may be resealed on relaxation. In addition, dystrophinopathy causes secondary defects of various dystrophin-associated proteins suggesting that defects in cell signaling participate in the pathologic process. With regard to other sarcolemmopathies, we discuss pathological mechanisms based on available data.

A new congenital form of X-linked autophagic vacuolar myopathy

In a new family with X-linked congenital autophagic vacuolar myopathy (AVM), seven affected boys presented with congenital hypotonia, dyspnea, and dysphagia with delayed motor milestones. Muscle pathology revealed autophagic vacuoles with sarcolemmal features, multilayered basal lamina with marked sarcolemmal deposition of C5-9 membrane attack complex and calcium, histologically indistinguishable from childhood-onset X-linked myopathy with excessive autophagy (XMEA). Haplotype analysis suggests that this new AVM and XMEA may be allelic despite different clinical presentations.