Recent advances in the pathology of alcoholic myopathy

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Victor R. Preedy and Junko Adachi. The presentations were (1) Alcoholic myopathy: Past, present and future, by Timothy J. Peters and Victor R. Preedy; (2) Protein adducts in the type I and II fiber-predominant muscles of the ethanol-fed rat, by Simon Worrall, Seppo Parkkila, and Onni Niemela; (3) Hydroperoxides and changes in alcoholic myopathy, by Junko Adachi, Migiwa Asamo, and Yasuhino Ueno; and (4) A close association between testicular atrophy, muscle atrophy, and the increase in protein catabolism after chronic ethanol administration, by Kunihiko Takeda, Masayoshi Yamauchi, Kazuhiko Sakamoto, Masaru Takagi, Hisato Nakajima, and Gotaro Toda.

Gonadotrophin and prolactin secretion in castrated male sheep following subcutaneous or intracranial treatment with testicular hormones

Interactions between testosterone, estradiol, and inhibin in the control of gonadotrophin secretion in males are poorly understood. Castrated rams were treated with steroid-free bovine follicular fluid (bFF), testosterone, or estradiol and for 7 d (2 x 2 x 2 factorial design). Given independently, none of the exogenous hormones affected follicle-stimulating hormone (FSH) concentrations, but the combination of one or both steroids with bFF reduced FSH secretion. Testosterone and estradiol reduced luteinizing hormone (LH) pulse frequency (there was no synergism), and bFF had no effect. Plasma prolactin concentrations were not affected by any treatment. To locate the central sites of steroid action, castrated rams were bilaterally implanted in the preoptic area (POA), ventromedial nucleus (VMH), or arcuate nucleus (ARC). These implants did not affect FSH or prolactin concentrations, or LH pulse amplitude. The frequency of the LH pulses was not affected by testosterone in any site. Estradiol located in the ARC, but not the POA or VMH, decreased LH pulse frequency. In summary, FSH secretion is controlled by synergistic interactions between inhibin and estradiol or testosterone, whereas GnRH/LH pulse frequency is controlled by testicular steroids. Estradiol acts partly, at least, in the ARC, but the central site of action, testosterone remains unknown.

Progressive dysgraphia in a case of posterior cortical atrophy

Dysgraphia (agraphia) is a common feature of posterior cortical atrophy (PCA). However, detailed analyses of these spelling and writing impairments are infrequently conducted. LM is a 59-year-old woman with dysgraphia associated with PCA. She presented with a two-year history of decline in her writing and dressmaking skills. A 3D T-1-weighted MRI scan confirmed selective bi-parietal atrophy, with relative sparing of the hippocampi and other cortical regions. Analyses of LM's preserved and impaired spelling abilities indicated mild physical letter distortions and a significant spelling deficit characterised by letter substitutions, insertions, omissions, and transpositions that was systematically sensitive to word length while insensitive to real word versus nonword category, word frequency, regularity, imagery, grammatical class and ambiguity. Our findings suggest a primary graphemic buffer disorder underlies LM's spelling errors, possibly originating from disruption to the operation of a fronto-parietal network implicated in verbal working memory.

Selective loss of expression of glutamate GluR2/R3 receptor subunits in cerebellar tissue from a patient with olivopontocerebellar atrophy

Expression of the mRNAs encoding the astrocytic (EAAT1, EAAT2) and neuronal (EAAT3, EAAT4) excitatory amino acid transporters and the AMPA-type glutamate receptor subunits GluR2 and GluR3 was investigated in postmortem cerebellar extracts from a patient with olivopontocerebellar atrophy (OPCA) and in material from three age-matched controls. Decreased expression in the steady state level of EAAT4 mRNA in the OPCA sample was correlated with the selective loss of Purkinje cells. Neuropathological evaluation revealed reactive gliosis and concomitantly increased expression of the mRNA encoding astrocytic glial fibrillary acidic protein (GFAP). Expression of the mRNAs encoding the AMPA receptor subunits GluR2 and GluR3 subunits was found to be decreased in OPCA suggesting that excitotoxic mechanism could play a role in the pathogenesis of the selective neuronal cell death in this disorder.

Testicular myxosporidiasis in anurans, with a description of Myxobolus fallax n. sp.

During studies of amphibian sperm cryopreservation, a new species of myxosporidean parasite (Myxozoa, Myxosporae) was observed in the testes of the Australian dwarf green tree frog Litoria fallax (Peters). Myxosporidiasis was found to have no affect on L. fallax body condition or sperm numbers. Myxobolus spores from L. fallax are morphologically distinct from Myxobolus hylae spores (infecting the sympatric Litoria aurea Lesson) and the three previously named (exotic to Australia) Myxobolus species found in anurans. Myxobolus fallax n. sp. is characterised by: pseudocyst white, spherical to ovoid, 141 x74 to 438 x337 mum in diameter (mature); plasmodium with spores loosely arranged within interior. Spores ovoid 13.4 +/- 0.5 (12.6-14.6) mum length, 9.5 +/- 0.4 (8.3-10.6) mum width, 6.8 +/- 0.4 (6.5-7.6) mum depth, 1.4 +/- 0.1 (1.3-1.6) length/width; polar capsules broadly pyriform and equal in size 4.2 +/- 0.3 (3.3-4.7) mum length, 2.4 +/- 0.2 (2.1-2.8) mum width; filament coils 7-8, wound tightly and perpendicular to the longitudinal axis of the capsule; polar filament 34 +/- 7.0 (18-50) mum length; intercapsular appendix and sutural ridge folds absent; and iodinophilous vacuole and mucous envelope lacking. In addition to this new species, data from archival samples of M. hylae are provided which show two morphologically distinct spore types. Both appeared rarely in the same pseudocysts and we cautiously retain the single species.

Mapping of autosomal recessive chronic distal spinal muscular atrophy to chromosome 11q13

Distal spinal muscular atrophy is a heterogeneous group of neuromuscular disorders caused by progressive anterior born cell degeneration and characterized by progressive motor weakness and muscular atrophy, predominantly in the distal parts of the limbs. Here we report on chronic autosomal recessive distal spinal muscular atrophy in a large, inbred family with onset at various ages. Because this condition had some of the same clinical features as spinal muscular atrophy with respiratory distress, we tested the disease gene for linkage to chromosome 11q and mapped the disease locus to chromosome 11q13 in the genetic interval that included the spinal muscular atrophy with respiratory distress gene (D11S1889-D11S1321, Z(max) = 4.59 at theta = 0 at locus D11S4136). The sequencing of IGHMBP2, the human homologue of the mouse neuromuscular degeneration gene (nmd) that accounts for spinal muscular atrophy with respiratory distress, failed to detect any mutation in our chronic distal spinal muscular atrophy patients, suggesting that spinal muscular atrophy with respiratory distress and chronic distal spinal muscular atrophy are caused by distinct genes located in the so-me chromosomal region. In addition, the high intrafamilial variability in age at onset raises the question of whether nonallelic modifying genes could be involved in chronic distal spinal muscular atrophy.

Hypermethylation of the 5 ' CpG island of the gene encoding the serine protease Testisin promotes its loss in testicular tumorigenesis

The Testisin gene (PRSS21) encodes a glycosylphosphatidylinositol (GPI)-linked serine protease that exhibits testis tissue-specific expression. Loss of Testisin has been implicated in testicular tumorigenesis, but its role in testis biology and tumorigenesis is not known. Here we have investigated the role of CpG methylation in Testisin gene inactivation and tested the hypothesis that Testisin may act as a tumour suppressor for testicular tumorigenesis. Using sequence analysis of bisulphite-treated genomic DNA, we find a strong relationship between hypermethylation of a 385 bp 50 CpG rich island of the Testisin gene, and silencing of the Testisin gene in a range of human tumour cell lines and in 100% (eight/eight) of testicular germ cell tumours. We show that treatment of Testisin-negative cell lines with demethylating agents and/or a histone deacetylase inhibitor results in reactivation of Testisin gene expression, implicating hypermethylation in Testisin gene silencing. Stable expression of Testisin in the Testisin-negative Tera-2 testicular cancer line suppressed tumorigenicity as revealed by inhibition of both anchorage-dependent cell growth and tumour formation in an SCID mouse model of testicular tumorigenesis. Together, these data show that loss of Testisin is caused, at least in part, by DNA hypermethylation and histone deacetylation, and suggest a tumour suppressor role for Testisin in testicular tumorigenesis.

Testicular development of Zebu bulls after chronic treatment with a gonadotropin-releasing hormone agonist

The objective was to compare testis characteristics of Zebu bulls treated with the GnRH agonist, deslorelin, at different times and for different durations during their development. An additional objective was to determine the usefulness of a stain for the transcription factor GATA-binding protein 4 (GATA-4) as a specific marker for Sertoli cell nuclei in cattle. Bulls (54) were allocated to nine groups (n = 6) and received s.c. deslorelin implants as follows: G1 = from birth to 3 mo of age; G2 = from 3 to 6 mo; G3 = from 6 to 9 mo; G4 = from 9 to 12 mo; G5 = from birth to 15 mo; G6 = from 3 to 15 mo; G7 = from 6 to 15 mo; G8 = from 12 to 15 mo; and G9 (control) = no implant. Bulls were castrated at 19 mo of age. Paraffin sections (10 mu m) were subjected to quantitative morphometry and GATA-4 immunohistochemistry. At castration, all bulls in the control group (6/6) had attained puberty (scrotal circumference ! 28 cm), whereas a smaller proportion (P < 0.05) had reached puberty in G2 (2/5) and G6 (1/ 6). Bulls in G2 and G6 also had a lesser (P < 0.05) testis weight compared with the control group. Total volume of seminiferous epithelium and total daily sperm production in G2 and G6 were only half that observed in the control group. Spermatids were observed in less than 50% of seminiferous tubules in G2, G6, and G7 compared with 82% in the control group (P < 0.05). Staining for GATA-4 was specific for and abundant in the Sertoli cell nucleus in both pre- and postpubertal bulls, and no other cell nucleus inside the seminiferous tubule was positive for GATA-4. Total number of Sertoli cells was not affected by treatment (P = 0.45), but nuclear volume was smaller in G2 and G6 (P < 0.05) compared with the control group. In conclusion, treatment of Zebu bulls with deslorelin had no apparent beneficial effect on testis development and delayed puberty when treatment was initiated at 3 mo of age. Staining for GATA-4 was a useful method for identifying and quantifying Sertoli cell nuclei in both pre- and postpubertal bulls.

Genetic basis of human testicular germ cell cancer: insights from the fruitfly and mouse

The prevalence of tumours of the germ line is increasing in the male population. This complex disease has a complex aetiology. We examine the contribution of genetic mutations to the development of germ line tumours in this review. In particular, we concentrate on fly and mouse experimental systems in order to demonstrate that mutations in some conserved genes cause pathologies typical of certain human germ cell tumours, whereas other mutations elicit phenotypes that are unique to the experimental model. Despite these experimental systems being imperfect, we show that they are useful models of human testicular germ cell tumourigenesis.

Rapid Atrophy of the Lumbar Multifidus Follows Experimental Disc or Nerve Root Injury.

Study Design. Experimental study of muscle changes after lumbar spinal injury. Objectives. To investigate effects of intervertebral disc and nerve root lesions on cross-sectional area, histology and chemistry of porcine lumbar multifidus. Summary of Background Data. The multifidus cross-sectional area is reduced in acute and chronic low back pain. Although chronic changes are widespread, acute changes at 1 segment are identified within days of injury. It is uncertain whether changes precede or follow injury, or what is the mechanism. Methods. The multifidus cross-sectional area was measured in 21 pigs from L1 to S1 with ultrasound before and 3 or 6 days after lesions: incision into L3 - L4 disc, medial branch transection of the L3 dorsal ramus, and a sham procedure. Samples from L3 to L5 were studied histologically and chemically. Results. The multifidus cross-sectional area was reduced at L4 ipsilateral to disc lesion but at L4 - L6 after nerve lesion. There was no change after sham or on the opposite side. Water and lactate were reduced bilaterally after disc lesion and ipsilateral to nerve lesion. Histology revealed enlargement of adipocytes and clustering of myofibers at multiple levels after disc and nerve lesions. Conclusions. These data resolve the controversy that the multifidus cross-sectional area reduces rapidly after lumbar injury. Changes after disc lesion affect 1 level with a different distribution to denervation. Such changes may be due to disuse following reflex inhibitory mechanisms.

Testicular germ cell tumors exhibit evidence of hormone dependence

The aim of this investigation was to test the hypothesis that testicular germ cell tumors (TGCTs) are hormone-dependent cancers. Human TGCT cells were implanted in the left testis of male severe combined immunodeficient mice receiving either no treatment or hormone manipulation treatment [blockade of gonadotropin-releasing hormone secretion and/or signaling using leuprolide or leuprolide plus exogenous testosterone]. Real-time RT-PCR analysis was used to determine the expression profiles of hormone pathway-associated genes. Tumor burden was significantly smaller in mice receiving both leuprolide and testosterone. Real-time RTPCR analysis of follicle-stimulating hormone (FSH) receptor, luteinizing hormone (LH) receptor and P450 aromatase revealed changes in expression in normal testis tissue related to presence of xenograft tumors and manipulation of hormone levels but a complete absence of expression of these genes in tumor cells themselves. This was confirmed in human specimens of TGCT. Reduced TGCT growth in vivo was associated with significant downregulation of LH receptor and P450 aromatase expression in normal testes. In conclusion, manipulation of hormone levels influenced the growth of TGCT in vivo, while the presence of xenografted tumors influenced the expression of hormone-related genes in otherwise untreated animals. Human TGCTs, both in the animal model and in clinical specimens, appear not to express receptors for FSH or LH. Similarly, expression of the P450 aromatase gene is absent in TGCTs. Impaired estrogen synthesis and/or signaling may be at least partly responsible for inhibition of TGCT growth in the animal model. (c) 2005 Wiley-Liss, Inc.