Arg(184)His mutant GTP cyclohydrolase I, causing recessive hyperphenylalaninemia, is responsible for dopa-responsive dystonia with parkinsonism: a case report.

We describe a 54-year-old man with dominant adult-onset dopa-responsive dystonia (DRD) with parkinsonism caused by an Arg184His mutation in guanosine 5'-triphosphate cyclohydrolase I (GCH-I). This is the first mutation in the GCH-I gene that has been proven to be responsible for both recessive and dominant phenotypes.     

一种新的被毛突变小鼠及其生物学特性的初步研究

在ＢＡＬＢ／ｃ小鼠生产群中，１罐繁殖鼠生下２只被毛稀疏的仔鼠。该对仔鼠成年后进行兄妹交配，后代出现三种表型：被毛紧披，生长快，繁殖力强的正常全毛小鼠；完全无毛，有胸腺，生长慢，性成熟晚，雄性隐睾率高，雌性窝产仔数少的无毛鼠；被毛稀疏，生长较快，繁殖率较高的中间态稀毛鼠。三种小鼠皆能在开放系统中生存，寿命１．５－２年。对这些小鼠进行交配试验，结果表明：此种突变由位于常染色体上的单对基因控制，呈半显性     

Orofacial and gastrointestinal hyperplasia and neoplasia in smad4+/− and elf+/−/smad4+/− mutant mice

Background:  Smad4 is vital to the roles of Smads 2 and 3 in transforming growth factor-beta (TGF)-β signal transduction, and inactivated Smad4 is common to human gastrointestinal cancers. The embryonic liver fodrin (ELF) is a β-spectrin that facilitates the nuclear translocation of activated Smad4.
Methods:  Smad4 ^+/− mice, known to develop gastrointestinal cancer, were crossbred with elf ^+/− mice. The smad4 ^+/− and smad4 ^+/−/ elf ^+/− offspring were autopsied as abnormalities developed.
Results:  In addition to polyps and adenocarcinomas of the stomach and duodenum, the smad4 ^+/− mice developed squamous cell carcinomas of the skin, oral mucosa and forestomach, benign neoplasms of connective tissue and lacrimal gland, and a lymphoma. The smad4 ^+/−/ elf ^+/− mice developed extensive hyperplasia and neoplasia of the gastric mucosa.
Conclusion:  These findings indicate that investigating interactions among smad4 , elf , and other genes involved in TGF-β signaling should be useful in further delineating the processes of neoplasia in a wide variety of tissues.     

HSW-毒素诱发和筛选小麦抗根腐病变体的研究

以小麦根腐病菌００２号菌株产生的致病毒素（ＨＳＷ－毒素）为选择剂，选用春、冬小麦品种、品系以及杂种的花药和幼穗进行离体培养，并结合物理诱变技术，已获得抗根腐病的植株，用根腐病菌分生孢子接种鉴定，再生植株５０株中有１２株抗病     

Exaggerated cyclic AMP accumulation and glial cell reaction in the cerebellum during Purkinje cell degeneration in pcd mutant mice

The Purkinje cell degeneration mutant (pcd) is characterized by a complete loss of cerebellar Purkinje cells. Norepinephrine causes an accumulation of cyclic AMP in the cerebellum of pcd that is far greater than in normal mice. Experiments were conducted 1) to correlated changes in the cyclic-nucleotide response with a histologic examination of the cerebellum during neuronal loss and 2) to examine the role of cyclic AMP catabolism and adenosine receptor interactions in the phenomenon. The greatest elevation in cyclic AMP occurred between 30 and 128 days of age when a severe astrocytic response was demonstrated throughout the cerebellar cortex. Purkinje cells had degenerated by 45 days of age. Norepinephrine elicited a smaller increase in cyclic AMP from 155-day-old mice than at earlier ages, and the response continued to decrease with age; at 270 days, equal accumulation, and at 365 days. lower accumulation of cyclic AMP was detected in pcd cerebella. During this time, the Purkinje cell debris had been removed, the granule cell layer was depleted of granule cells, and the molecular layer was deprived of a large number of parallel fibers. However, although phagocytosis of neuronal debris was completed, large numbers of astrocytic processes were still seen in the neuropil. Biochemical experiments in vitro established that the exaggerated accumulation of cyclic AMP in the presence of norepinephrine was not due to lower catabolism of cyclic AMP, a synergistic interaction with adenosine, or a result of lower protein in the pcd cerebellum. The correlates of heightened norepinephrine-stimulated accumulation of cyclic AMP with neuronal loss and the glial cell reaction might indicate that cyclic nucleotides play a role in controlling some glial cell functions, ie, proliferation, migration, and phagocytosis.     

Heterologous synapses upon purkinje cells in the cerebellum of the reeler mutant mouse: An experimental light and electron microscopic study

The projections of the spinal cord upon the cerebellum of normal and Reeler mutant mice were compared by light and electron microscopic methods after hemicordotomy. In both genotypes this afferent system projects to the cerebellar cortex and to the roof nuclei. In the Reeler, there is an additional projection among the Purkinje cells and interneurons of the central cerebellar mass. In both normal and Reeler cerebellar cortex this mossy fiber system terminates as large glomeruli. In Reeler the spinal projection also gives rise to a smaller terminal which is distributed both to the cortex and the central cerebellar mass. In both genotypes the dendrites of granule cells and the somata and dendrites of Golgi cells are synaptic targets of the glomeruli of the cortical projection. In Reeler both the glomeruli and smaller terminals also form heterologous synaptic contacts with dendritic spines of heterotopic intracortical and subcortical Purkinje cells. In both genotypes the synapses are exclusively type I. A second class of heterologous synapse, a type I junction between axons of Golgi cells and Purkinje cell spines, is also recognized in electron micrographs. The present study is the first unequivocal demonstration by experimental hodologic method of heterologous synaptic junctions in the mammalian central nervous system. The existence of such junctions in the cytoarchitectonically anomolous cerebellum of this mutant emphasizes the critical role played by the cellular environment in shaping neural circuits in the developing nervous system.     

Similarities and dissimilarities between two myelin deficient mutant mice, Shiverer andmld

In the brain of Shiverer and mld mutant mice, myelin is poorly compacted and the major dense line of the myelin is practically missing. Major biochemical differences were detected between mutations. In mld myelin, myelin basic proteins are mainly affected and 2', 3'-cyclic nucleotide 3'-phosphodiesterase (CNP) exhibits a very high specific activity. In Shiverer myelin, in addition to basic proteins, all major myelin proteins are also decreased while CNP specific activity is moderately increased.     

Cerebellar gangliosides and phospholipids in mutant mice with ataxia and epilepsy: the Tottering/Leaner syndrome

The effects of selected CNS lesions on the ovulatory cycle as well as the distribution of LHRH terminals in the median eminence of the female guinea pig were examined. Radiofrequency lesions were placed in the medial preoptic area (MPOA) or suprachiasmatic nucleus (SCN). Animals were studied for varying lengths of time (1–5 months) following lesion placement. The occurrence of at least two ovulatory cycles was determined by cyclicity in vaginal opening, the presence of viable corpora lutea and measurements of luteal phase elevations in serum progesterone. The distribution of LHRH immunoreactivity was determined by immunocytochemical procedures on Bouin's fixed, paraffin-embedded brain sections. Lesions of the MPOA or SCN resulted in different degrees of loss of LHRH fibers in the zona externa of the ventral and lateral aspects of the infundibular stalk as well as complete loss of terminals throughout the zona interna. Despite depletion of LHRH fibers, all animals with SCN (n= 8) and the majority with MPOA (4/6) lesions showed regular ovulatory cycles. Two females with MPOA lesions presented two different anovulatory syndromes. Anovulation appeared unrelated to the size or site of the lesions or the degree of depletion of LHRH fibers in the infundibulum. It would appear that these brain areas and their LHRH projections are not essential for cyclic gonadotropic release.