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121.
Antisera produced in rabbits against pure fractions of cholinergic vesicles from Narcine brasiliensis were used to study cholinergic organelles in rat motor neurons. The indirect immunofluorescence method was used on perfusion-fixed material. The rats were surgically sympathectomized to remove sympathetic adrenergic and cholinergic nerves from the sciatic nerve. In the intact animal immunoreactive material, likely to represent cholinergic vesicles, was observed in motor endplates, identified by labelling with rhodamine-conjugated α-bungarotoxin or with subsequent acetylcholinesterase staining. The motor perikarya contained very little immunoreactive material. Non-terminal axons were virtually devoid of immunofluorescence in the intact animal. After crushing the sciatic nerve, immunoreactive material (likely to represent axonal cholinergic organelles) accumulated rapidly on both sides of the crush, indicating a rapid bidirectional transport. The transport was sensitive to local application of mitotic inhibitors.The axons which accumulated immunoreactive organelles were motor axons, as demonstrated by various procedures: (1) Cutting of ventral roots prevented accumulation of immunoreactive material in the nerve. (2) Deafferentation did not notably influence accumulations of immunoreactive material. (3) Ligated axons with immunoreactive material were acetylcholinesterase positive when identification was made on the same section; the intra-axonal distribution of immunoreactive material and acetylcholinesterase was not identical, however, and the Narcine antisera did not cross-react with bovine acetylcholinesterase in a solid phase immunoassay. (4) Most axons in ventral roots, but not in dorsal roots, accumulated strongly fluorescent immunoreactive material, while axons in dorsal roots contained weakly fluorescent material. On the other hand, substance P-like immune reactivity was present in many dorsal root axons, but only very rarely in ventral roots.It is suggested that the antisera against Narcine cholinergic vesicles can be used as a marker for cholinergic organelles in the motor neuron, and may be an important tool for studying the axonal cholinergic vesicles. It cannot, however, be used to identify cholinergic structures in unknown locations because it recognizes common antigenic determinants in transmitter organelles of other nerves e.g. adrenergic nerves. The axonal cholinergic organelles may carry important molecules, other than acetylcholine to the nerve endings. 相似文献
122.
Human endogenous retroviruses (HERVs) have recently been suggested as mediators of normal biological processes such as cellular differentiation and regulation of gene expression. Moreover, a direct role for HERVs in pathogenesis and the development of disease is now better appreciated. Elucidation of the mechanisms regulating HERV biology should provide information about fundamental cellular activities and the pathogenesis of multifactorial diseases such as cancer and autoimmune disease. The importance of understanding the roles of HERVs is underscored by the recently obtained insight that activation of endogenous retroviruses poses potential risks following xenotransplantation and in gene therapy using retroviral vectors. Furthermore, HERV-encoded superantigens have recently been implicated as causes of autoimmune disease. This review discusses the established and possible biological roles of HERVs, and proposes hypotheses concerning their involvement as mediators of fundamental cellular responses. We propose that the evolutionary persistence of endogenous retroviruses in the genomes of eukaryotic cells reflects their indispensability in important normal functions in specialized cellular environments. HERVs can also be potentially hazardous through their involvement in the development of disease. In addition, the creation of new retroviruses can occur through recombination, between different HERVs and between HERVs and exogenous retroviruses. 相似文献
123.
Jesper L. R. Andersson Anders Lilja P. Hartvig Bengt Långström Torsten Gordh Hermann Handwerker E. Torebjörk 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,117(2):192-199
Regional cerebral blood flow was measured with positron emission tomography (PET) in six healthy volunteers at rest and during
experimentally induced, sustained cutaneous pain on the dorsum of the right hand or on the dorsum of the right foot. Pain
was inflicted by intracutaneous injection of capsaicin, providing a mainly C-fibre nociceptive stimulus. Statistical analysis
showed significant activations along the central sulcus (SI) area when comparing pain in the hand to pain in the foot. Separate
comparison of both pain states to a baseline revealed different locations along the central sulcus for hand pain and foot
pain. The encountered differences are consistent with what is previously known about the somatotopics of non-painful stimuli.
When comparing painful stimuli to baseline, the contralateral anterior cingulate gyrus, the ipsilateral anterior insular cortex
and the ipsilateral prefrontal cortex were implicated. The results are consistent with an involvement of SI in the spatial
discrimination of acute cutaneous pain.
Received: 17 October 1996 / Accepted: 12 May 1997 相似文献
124.
Gas chromatographic determination of D-arabinitol/L-arabinitol ratios in urine: a potential method for diagnosis of disseminated candidiasis. 总被引:1,自引:2,他引:1
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A gas chromatographic procedure was developed to determine the relative amounts of D- and L-arabinitol in urine. Samples were filtered, diluted, purified through extractions, evaporated, and treated with trifluoroacetic anhydride; the arabinitol derivatives thus obtained were separated on a chiral stationary phase and registered by using an electron-capture detector. Urine samples from a patient with disseminated candidiasis had higher D-arabinitol/L-arabinitol ratios (referred to as D/L-arabinitol ratios)--up to 19.0--than samples from 96 study individuals with no signs of deep Candida infections (range, 1.1 to 4.5). D/L-Arabinitol ratios in urine samples from hospitalized patients without Candida infections were slightly higher than those in samples from healthy individuals; ratios in urine from children were slightly higher than those in adult urine samples. The D/L-arabinitol ratios in several urine samples culture positive for Candida albicans, but from patients without symptoms of disseminated candidiasis, did not differ from those in the urine of healthy individuals. The described gas chromatographic method is straightforward and can be implemented clinically to determine urine D/L-arabinitol ratios as a means of diagnosing disseminated candidiasis. 相似文献
125.
Dahl N; Pigg M; Ristoff E; Gali R; Carlsson B; Mannervik B; Larsson A; Board P 《Human molecular genetics》1997,6(7):1147-1152
Severe glutathione synthetase (GS) deficiency is a rare genetic disorder
with neonatal onset. The enzymatic block of the gamma-glutamyl cycle leads
to a generalized glutathione deficiency. Clinically affected patients
present with severe metabolic acidosis, 5- oxoprolinuria, increased rate of
hemolysis and defective function of the central nervous system. The
disorder is inherited in an autosomal recessive mode and, until recently,
the molecular basis has remained unknown. We have sequenced 18 GS alleles
associated with enzyme deficiency and we detected missense mutations by
direct sequencing of cDNAs and genomic DNA. In total, 13 different
mutations were identified. Four patients were found to be compound
heterozygotes and two individuals were apparently homozygous. Reduced
enzymatic activities were demonstrated in recombinant protein expressed
from cDNAs in four cases with different missense mutations. The results
from biochemical analysis of patient specimens, supported by the properties
of the expressed mutant proteins, indicate that a residual activity is
present in affected individuals. Our results suggest that complete loss of
function of both GS alleles is probably lethal. It is postulated that
missense mutations will account for the phenotype in the majority of
patients with severe GS deficiency.
相似文献
126.
127.
Albert L Sheffer Mike Silverman Ann J Woolcock Patricia V Díaz Bengt Lindberg Bertil Lindmark 《Annals of allergy, asthma & immunology》2005,94(1):48-54
BACKGROUND: The Inhaled Steroid Treatment as Regular Therapy in Early Asthma (START) study is a worldwide, randomized, prospective study to investigate early intervention with inhaled corticosteroids in recent-onset mild persistent asthma. OBJECTIVE: To evaluate the safety and tolerability of long-term treatment with once-daily budesonide therapy in patients with mild persistent asthma. METHODS: Patients aged 5 to 66 years with mild persistent asthma for fewer than 2 years and no previous regular corticosteroid treatment received budesonide or placebo once daily for 3 years, in addition to their usual asthma therapy. The daily budesonide dose was 200 microg for children younger than 11 years and 400 microg for those 11 years or older. RESULTS: Overall, 7,221 patients were included in the safety analysis, and a total of 21,520 adverse events were reported (10,850 in the budesonide group and 10,670 in the placebo group). The most commonly reported events included respiratory infections, rhinitis, pharyngitis, bronchitis, viral infections, and sinusitis. The number of deaths and serious adverse events were similar for children and adults in both treatment groups. Fewer asthma-related serious adverse events were reported with budesonide (162) compared with placebo (276). Oral candidiasis was reported more frequently with budesonide (1.2%) than with placebo (0.5%); the frequencies of other adverse effects previously reported to be associated with inhaled corticosteroids (psychiatric disorders, skin disorders, and allergic reactions) were similar. CONCLUSIONS: Three-year treatment with budesonide once daily (200 or 400 microg) is safe and well tolerated in children and adults with newly detected mild persistent asthma. 相似文献
128.
129.
Bilateral olfactory bulbectomy or destruction of the olfactory epithelium of rats resulted in elevated body temperature in room temperature, and lowered water/food ratio in 30 degrees ambient temperature. The results suggest the involvement of the olfactory system in the thermoregulation. 相似文献
130.
Razifar P Lubberink M Schneider H Långström B Bengtsson E Bergström M 《BMC medical imaging》2005,5(1):3