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31.
Summary Immunocytochemical localization of dopamine -hydroxylase (DBH) was used to study the synthesis and storage sites of norepinephrine (noradrenaline) in the rat and cat carotid bodies. In the rat carotid body some parenchymal cells exhibited strong DBH-like immunoreactivity (DBH-I), while others displayed only faint DBH-I. In a typical parenchymal cell cluster, most cells with strong DBH-I were irregular in shape and appeared to partially surround those with weak DBH-I which usually were rounded in contour. In the cat carotid body most parenchymal cells showed a strong to moderate DBH-I. In both the rat and cat carotid bodies varicose nerve fibres with DBH-I were associated primarily with blood vessels. All autonomic ganglion cells examined, which were associated with the rat carotid body, showed DBH-I. Electron microscopy revealed that most DBH-I in the strongly positive cells of the rat carotid body was associated with dense granules (possibly corresponding to dense-cored vesicles of various sizes), although some was found in other sites. In oval cells with less DBH-I, reactivity resided in some of the large granules. In the cat carotid body the glomus cells contained more granules of various sizes and shapes than did those of the rat carotid body. Most of the cat glomus cell granules exhibited DBH-I activity. Our results indicate that some of glomus cells in the rat and most of the glomus cells in the cat contain DBH and therefore may be sites of norepinephrine synthesis. 相似文献
32.
Diffusion in gel-enzyme-linked immunosorbent assay—a new serological test for leptospirosis 下载免费PDF全文
A new serological test, diffusion in gel-enzyme-linked immunosorbent assay (DIG-ELISA) was developed and compared with the microscopic agglutination test (MAT) for the serological diagnosis of leptospirosis. The results suggest that DIG-ELISA is a viable alternative to the MAT because of its simplicity, sensitivity, versatility and potential for standardisation. 相似文献
33.
Mutations in the TSC2 gene: analysis of the complete coding sequence using the protein truncation test (PTT) 总被引:4,自引:0,他引:4
Mutations in the TSC2 gene on chromosome 16p13.3 are responsible for
approximately 50% of familial tuberous sclerosis (TSC). The gene has 41
small exons spanning 45 kb of genomic DNA and encoding a 5.5 kb mRNA. Large
germline deletions of TSC2 occur in <5% of cases, and a number of small
intragenic mutations have been described. We analysed mRNA from 18
unrelated cases of TSC for TSC2 mutations using the protein truncation test
(PTT). Three cases were predicted to be TSC2 mutations on the basis of
linkage analysis or because a hamartoma from the patient showed loss of
heterozygosity for 16p13.3 markers. Three overlapping PCR products,
covering the complete coding sequence of mRNA, were generated from
lymphoblastoid cell lines, translated into 35S-methionine labelled protein,
and analysed by SDS-PAGE. PCR products showing PTT shifts were directly
sequenced, and mutations confirmed by restriction enzyme digestion where
possible. Six PTT shifts were identified. Five of these were caused by
mutations predicted to produce a truncated protein: (i) a sporadic case
showed a 32 bp deletion in exon 11, and a mutant mRNA without exon 11 was
produced; the normal exon 10 was also spliced out; (ii) a sporadic case had
a 1 bp deletion in exon 12 (1634delT); (iii) a TSC2-linked mother and
daughter pair had a G-->T transversion in exon 23 (G2715T) introducing a
cryptic splice site causing a 29 bp truncation of mRNA from exon 23; (iv) a
sporadic case showed a 2 bp deletion in exon 36; (v) a sporadic case showed
a 1 bp insertion disrupting the donor splice site of exon 37 (5007+2insA),
resulting in the use of an upstream exonic cryptic splice site to cause a
29 bp truncation of mRNA from exon 37. In one case, the PTT shift was
explained by in-frame splicing out of exon 10, in the presence of a normal
exon 10 genomic sequence. Alternative splicing of exon 10 of the TSC2 gene
may be a normal variant. Three 3rd base substitution polymorphisms were
also detected during direct sequencing of PCR products. Confirmed mutations
were identified in 28% of the families studied and on the assumption that
half of the sporadic cases should have TSC2 mutations, a crude estimate of
the detection rate would be 60%. This compares favourably with other
screening methods used for TSC2, notably SSCP, and since PTT involves much
less work it may be the method of choice.
相似文献
34.
George N Papanikolaou Maria S Baltogianni Despina G Contopoulos-Ioannidis Anna-Bettina Haidich Ioannis A Giannakakis John PA Ioannidis 《BMC medical research methodology》2001,1(1):3
Background
Guidelines published in major medical journals are very influential in determining clinical practice. It would be essential to evaluate whether conflicts of interests are disclosed in these publications. We evaluated the reporting of conflicts of interest and the factors that may affect such disclosure in a sample of 191 guidelines on therapeutic and/or preventive measures published in 6 major clinical journals (Annals of Internal Medicine, BMJ, JAMA, Lancet, New England Journal of Medicine, Pediatrics) in 1979, 1984, 1989, 1994 and 1999.Results
Only 7 guidelines (3.7%) mentioned conflicts of interest and all were published in 1999 (17.5% (7/40) of guidelines published in 1999 alone). Reporting of conflicts of interest differed significantly by journal (p=0.026), availability of disclosure policy by the journal (p=0.043), source of funding (p < 0.001) and number of authors (p=0.004). In the entire database of 191 guidelines, a mere 18 authors disclosed a total of 24 potential conflicts of interest and most pertained to minor issues.Conclusions
Despite some recent improvement, reporting of conflicts of interest in clinical guidelines published in influential journals is largely neglected.35.
Dal Zotto L; Quaderi NA; Elliott R; Lingerfelter PA; Carrel L; Valsecchi V; Montini E; Yen CH; Chapman V; Kalcheva I; Arrigo G; Zuffardi O; Thomas S; Willard HF; Ballabio A; Disteche CM; Rugarli EI 《Human molecular genetics》1998,7(3):489-499
We have recently reported isolation of the gene responsible for X- linked
Opitz G/BBB syndrome, a defect of midline development. MID1 is located on
the distal short arm of the human X chromosome (Xp22. 3) and encodes a
novel member of the B box family of zinc finger proteins. We have now
cloned the murine homolog of MID1 and performed preliminary expression
studies during development. Mid1 expression in undifferentiated cells in
the central nervous, gastrointestinal and urogenital systems suggests that
abnormal cell proliferation may underlie the defect in midline development
characteristic of Opitz syndrome. We have also found that Mid1 is located
within the mouse pseudoautosomal region (PAR) in Mus musculus , while it
seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a
recent acquisition of the M. musculus PAR. Genetic and FISH analyses also
demonstrated a high frequency of unequal crossovers in the murine PAR,
creating spontaneous deletion/duplication events involving Mid1. These data
provide evidence for the first time that genetic instability of the PAR may
affect functionally important genes. In addition, we show that MID1 is the
first example of a gene subject to X-inactivation in man while escaping it
in mouse. These data contribute to a better understanding of the molecular
content and evolution of the rodent PAR.
相似文献
36.
S. D. Stocker B. C. Steinbacher Jr. C. D. Balaban B. J. Yates 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,116(2):270-282
A region of the caudal ventrolateral medullary reticular formation (CVLM) participates in baroreceptor, vestibulosympathetic,
and somatosympathetic reflexes; the adjacent retroambigual area is involved in generating respiratory-related activity and
is essential for control of the upper airway during vocalization. However, little is known about the connections of the CVLM
in the cat. In order to determine the locations of terminations of CVLM neurons, the anterograde tracers Phaseolus vulgaris leucoagglutinin and tetramethylrhodamine dextran amine were injected into this region. These injections produced a dense concentration
of labeled axons throughout the lateral medullary reticular formation (lateral tegmental field), including the retrofacial
nucleus and nucleus ambiguus, regions of the rostral ventrolateral medulla, the lateral and ventrolateral aspects of the hypoglossal
nucleus, nucleus intercalatus, and the facial nucleus. A smaller number of labeled axons were located in the medial, lateral,
and commissural subnuclei of nucleus tractus solitarius, the A5 region of the pontine reticular formation, the ventral and
medial portions of the spinal and motor trigeminal nuclei, locus coeruleus, and the parabrachial nucleus. We confirmed the
projection from the CVLM to both the rostral ventrolateral medulla and lateral tegmental field using retrograde tracing. Injections
of biotinylated dextran amine or Fluorogold into these regions resulted in retrogradely labeled cell bodies in the CVLM. However,
the neurons projecting to the lateral tegmental field were located mainly dorsal to those projecting to the rostral ventrolateral
medulla, suggesting that these neurons form two groups, possibly with different inputs. Injections of retrograde tracers into
the lateral tegmental field and rostral ventrolateral medulla also produced labeled cell bodies in other regions, including
the medial and inferior vestibular nuclei and nucleus solitarius. These data are consistent with the view that the CVLM of
the cat is a multifunctional area that regulates blood pressure, produces vocalization, affects the shape of the oral cavity,
and elicits contraction of particular facial muscles.
Received: 18 February 1997 / Accepted: 27 March 1997 相似文献
37.
Determination of the parent of origin in nine cases of prenatally detected chromosome aberrations found after intracytoplasmic sperm injection 总被引:1,自引:17,他引:1
Van Opstal D; Los FJ; Ramlakhan S; Van Hemel JO; Van Den Ouweland AM; Brandenburg H; Pieters MH; Verhoeff A; Vermeer MC; Dhont M; In't Veld PA 《Human reproduction (Oxford, England)》1997,12(4):682-686
Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic
sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome
aberrations including two cases of 47,XXY, four cases involving a 45,X cell
line and three autosomal trisomies. Molecular analysis of the parental
origin of the deleted or supernumerary chromosome was performed by using
polymorphic microsatellite markers. Six cases involving a sex chromosome
abnormality were found to be of paternal origin while the two trisomic
cases that could be analysed were of maternal origin. Two cases involved
the same infertile couple who had two consecutive ICSI pregnancies
terminated because of a chromosome abnormality. The replaced embryos in
both cases originated from a single batch of ICSI fertilized oocytes of
which part was used to initiate the first pregnancy and part was
cryopreserved and used to initiate the second pregnancy.
相似文献
38.
Michael S. Yates C. Robin Hiley 《Pflügers Archiv : European journal of physiology》1979,379(2):219-222
The distribution of cardiac output was determined by 15 m radioactive microspheres in all the major organs of spontaneous, DOCA/NaCl and one kidney Goldblatt hypertensive rats and compared to normotensive Wistar rats. Although there were alterations in cardiac output distribution which were characteristic of each model of hypertension significant changes were common to all three were an increased distribution to skeletal muscle with decreases to the lungs, spleen and hepatosplanchnic tissues. The results suggest that alterations in peripheral resistance induced by hypertension are of unequal importance in the different vascular beds with certain vascular resistance changes occurring irrespective of the origin of the hypertension.Abbreviations used in this paper SHR
spontaneously hypertensive rats
- DOCA
deoxycorticosterone acetate
Supported by I.C.I. Pharmaceutical Ldt and the Mersey Regional Health Authority (Research Schemes No. 338). 相似文献
39.
M. Fauville-Dufaux B. Vanfleteren L. De Wit J. P. Vincke J. P. Van Vooren M. D. Yates E. Serruys J. Content 《European journal of clinical microbiology & infectious diseases》1992,11(9):797-803
A polymerase chain reaction (PCR) assay was developed for detection of mycobacteria using amplification of a 162 bp region of the genes coding for the mycobacterial antigen 85 complex. Strains belonging to theMycobacterium tuberculosis complex were further differentiated from non-tuberculous mycobacteria by hybridization of the PCR derived Southern blot with an internal oligonucleotide probe and washing under stringent conditions. The method allowed rapid and sensitive detection of mycobacterial DNA in uncultured clinical samples. PCR results obtained forMycobacterium tuberculosis in 206 specimens from 180 untreated patients gave a sensitivity of 93.9% and a specificity of 94.3% compared with the culture. PCR detected DNA fromMycobacterium tuberculosis in seven samples from patients with clinically evident tuberculosis in whom culture was negative. The results suggest that this PCR assay could be used for early and specific diagnosis of tuberculosis. 相似文献
40.
A longitudinal study of maternal serum inhibin-A, inhibin-B, activin-A, activin-AB, pro-alphaC and follistatin during pregnancy 总被引:6,自引:1,他引:6
Fowler PA; Evans LW; Groome NP; Templeton A; Knight PG 《Human reproduction (Oxford, England)》1998,13(12):3530-3536
Maternal serum concentrations of inhibin-A, inhibin-B, activin-A,
activin-AB, pro-alphaC-related inhibin forms, total follistatin, steroids
and gonadotrophins were measured longitudinally in six normal singleton
pregnancies. Maternal venous blood was collected randomly during a
spontaneous follicular phase prior to donor insemination, at 5, 7, 9, 11,
16, 20, 24, 28, 32 and 36 weeks after the first missed menses and in the
early puerperium. Steroid and gonadotrophin profiles conformed to previous
reports. While at week 5 of gestation inhibin-A, activin-A and follistatin
concentrations were similar to those at the follicular phase, all three
increased progressively (P < 0.001) to maximal concentrations in week
36: approximately 48-fold (3740 +/- 1349 ng inhibin-A/ml), approximately
22-fold (6109 +/- 1443 ng activin-A/ml) and approximately 10-fold (3563 +/-
418 ng follistatin/ml) higher. Pro- alphaC concentrations reached a maximum
in weeks 5 (approximately 5- fold, P < 0.001) and 36 (1027 +/- 174
pg/ml, P < 0.01). Inhibin-B (71 +/- 23 pg/ml prior to pregnancy) was
undetectable (<12 pg/ml) between week 5-16 of gestation but increased
slightly in the third trimester (26 +/- 7 pg/ml in week 36). Activin-AB was
undetectable throughout pregnancy. Post-partum concentrations of inhibin-A
(41 +/- 12 ng/ml), inhibin-B (<12 pg/ml), activin-A (950 +/- 149 pg/ml),
pro-alphaC (128 +/- 22 pg/ml) and follistatin (990 +/- 79 ng/ml) were
substantially lower than at week 36 of gestation. The activin-A:follistatin
ratio increased from 0.5 in week 5 to 1.8 in week 36, suggesting that more
free activin-A is available in the maternal circulation during late
pregnancy.
相似文献