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11.
Elizabeth Dorus Anthony P. Amarose Donald R. Tredway Frank R. Reale Richard Hatch Lucia F. Serrano 《Clinical genetics》1979,16(4):253-259
A 24-year-old female patient was referred for evaluation of primary amenorrhea. Endocrine studies showed elevated gonadotropins, consistent with gonadal failure. At laparoscopy, a normal nulligravid uterus, normal fallopian tubes, and bilateral streak gonads were observed. Histologic studies showed that the left gonad consisted entirely of fibrous tissue, confirming the presence of streak gonads. Chromosome banding studies of peripheral blood and cultures of tissue from the left gonad demonstrated a 46,X,rcp(X;11)(q22;q13) karyotype. A review of reports of X-autosome reciprocal translocations indicated that abnormal gonadal development is associated with break-points in the mid-region of the long arm of the X chromosome. 相似文献
12.
13.
Exogenous guanine was found to be incorporated into the nucleic acids of Chlamydia psittaci when the parasite was grown in HeLa cells containing hypoxanthine guanine phosphoribosyltransferase (EC 2.4.2.8) activity but not when the parasite was grown in transferase-deficient HeLa cells. No evidence for a chlamydia-specific transferase activity was found in either transferase-containing or transferase-deficient infected HeLa cells. It is concluded that C. psittaci is incapable of metabolizing guanine, but that the parasite can use host-generated guanine nucleotides as precursors for nucleic acid synthesis. 相似文献
14.
L J Anderson M H Hatch M R Flemister G E Marchetti Jr 《Journal of clinical microbiology》1984,20(3):405-408
To improve the ability to identify enterovirus-70 (EV-70) from patients with acute hemorrhagic conjunctivitis, we developed four monoclonal antibodies (MAbs) to EV-70. We reacted the four MAbs against nine previously characterized strains of EV-70 and heterologous viruses by virus neutralization, indirect immunofluorescence, and enzyme-linked immunosorbent assay (ELISA). Two of the MAbs neutralized all nine strains of EV-70 and none of the other enterovirus types tested. Two of the MAbs gave a positive reaction with all nine strains by indirect immunofluorescence, and three reacted with all nine strains by ELISA. None of the MAbs gave a positive reaction with heterologous viruses, including those associated with eye disease, by indirect immunofluorescence or ELISA. The two neutralizing MAbs failed to give a positive reaction with some of the strains of EV-70 by indirect immunofluorescence and ELISA, yet they neutralized these viruses. By ELISA with a polyclonal serum as capture antibody and a mixture of MAbs as detector antibody, we were able to detect from 10(2.2) to 10(5.8) 50% tissue culture infective doses of virus and to type lyophilized isolates of EV-70 sent from Taiwan from which we could not recover infectious virus. By choosing the appropriate MAb, or mixture of MAbs, we could construct a test which had the type specificity and strain sensitivity needed to type isolates of EV-70. 相似文献
15.
Boosting with poxviruses enhances Mycobacterium bovis BCG efficacy against tuberculosis in guinea pigs 下载免费PDF全文
Williams A Goonetilleke NP McShane H Clark SO Hatch G Gilbert SC Hill AV 《Infection and immunity》2005,73(6):3814-3816
Tuberculosis is rising in the developing world due to poor health care, human immunodeficiency virus type 1 infection, and the low protective efficacy of the Mycobacterium bovis BCG vaccine. A new vaccination strategy that could protect adults in the developing world from tuberculosis could have a huge impact on public health. We show that BCG boosted by poxviruses expressing antigen 85A induced unprecedented 100% protection of guinea pigs from high-dose aerosol challenge with Mycobacterium tuberculosis, suggesting a strategy for enhancing and prolonging the efficacy of BCG. 相似文献
16.
Proton spectroscopy study of the left dorsolateral prefrontal cortex in pediatric depressed patients
Caetano SC Fonseca M Olvera RL Nicoletti M Hatch JP Stanley JA Hunter K Lafer B Pliszka SR Soares JC 《Neuroscience letters》2005,384(3):321-326
The dorsolateral prefrontal cortex (DLPFC) plays an essential role in mood regulation and integration of cognitive functions that are abnormal in major depressive disorder (MDD). Few neuroimaging studies have evaluated the still maturing DLPFC in depressed children and adolescents. We conducted single voxel proton magnetic resonance spectroscopy ((1)H MRS) of the left DLPFC in 14 depressed children and adolescents (13.3 +/- 2.3 years old, 10 males) and 22 matched healthy controls (13.6 +/- 2.8 years old, 13 males). Depressed subjects had significantly lower levels of glycerophosphocholine plus phosphocholine (GPC + PC; or choline-containing compounds) and higher myo-inositol levels in the left DLPFC compared to healthy controls. In the depressed subjects, we found significant inverse correlations between glutamate levels and both duration of illness and number of episodes. In healthy controls there was a significant direct correlation between age and glutamine levels, which was not present in the patient group. Lower GPC + PC levels in pediatric MDD may reflect lower cell membrane content per volume in the DLPFC. Increased myo-inositol levels in MDD may represent a disturbed secondary messenger system. GPC + PC and myo-inositol abnormalities further demonstrate the involvement of DLPFC in pediatric MDD. 相似文献
17.
Liu JQ; Bai XF; Shi FD; Xiao BG; Li HL; Levi M; Mustafa M; Wahren B; Link H 《International immunology》1998,10(8):1139-1148
Induction of mucosal tolerance by inhalation of soluble peptides with
defined T cell epitopes is receiving much attention as a means of
specifically down-regulating pathogenic T cell reactivities in autoimmune
and allergic disorders. Experimental autoimmune encephalomyelitis (EAE)
induced in the Lewis rat by immunization with myelin basic protein (MBP)
and Freund's adjuvant (CFA) is mediated by CD4+ T cells specific for the
MBP amino acid sequences 68-86 and 87-99. To further define the principles
of nasal tolerance induction, we generated three different MBP peptides
(MBP 68-86, 87-99 and the non- encephalitogenic peptide 110-128), and
evaluated whether their nasal administration on day -11, -10, -9, -8 and -7
prior to immunization with guinea pig MBP (gp-MBP) + CFA confers protection
to Lewis rat EAE. Protection was achieved with the encephalitogenic
peptides MBP 68-86 and 87-99, MBP 68-86 being more potent, but not with MBP
110-128. Neither MBP 68-86 nor 87-99 at doses used conferred complete
protection to gp-MBP-induced EAE. In contrast, nasal administration of a
mixture of MBP 68-86 and 87-99 completely blocked gp-MBP-induced EAE even
at lower dosage compared to that being used for individual peptides. Rats
tolerized with MBP 68-86 + 87-99 nasally showed decreased T cell responses
to MBP reflected by lymphocyte proliferation and IFN-gamma ELISPOT assays.
Rats tolerized with MBP 68-86 + 87-99 also had abrogated MBP-reactive
IFN-gamma and tumor necrosis factor-alpha mRNA expression in lymph node
cells compared to rats receiving MBP 110-128 nasally, while similar low
levels of MBP-reactive transforming growth factor-beta and IL-4 mRNA
expressing cells were observed in the two groups. Nasal administration of
MBP 68-86 + 87-99 only slightly inhibited guinea pig spinal cord
homogenate-induced EAE, and passive transfer of spleen mononuclear cells
from MBP 68-86 + 87-99-tolerized rats did not protect naive rats from EAE.
Finally, we show that nasal administration of MBP 68-86 + 87-99 can reverse
ongoing EAE induced with gp-MBP, although higher doses are required
compared to the dosage needed for prevention. In conclusion, nasal
administration of encephalitogenic MBP peptides can induce antigen-specific
T cell tolerance and confer incomplete protection to gp-MBP-induced EAE,
and MBP 68-86 and 87-99 have synergistic effects. Non-regulatory mechanisms
are proposed to be responsible for tolerance development after nasal
peptide administration.
相似文献
18.
Cloning and sequence analysis of the major outer membrane protein gene of Chlamydia psittaci 6BC. 总被引:7,自引:0,他引:7 下载免费PDF全文
The gene encoding the major outer membrane protein (MOMP) of the psittacine Chlamydia psittaci strain 6BC was cloned and sequenced. N-terminal protein sequencing of the mature MOMP indicated that it is posttranslationally processed at a site identical to the site previously identified in the MOMP of Chlamydia trachomatis L2. The nucleotide sequence of the C. psittaci 6BC MOMP gene was found to be 67 to 68% identical to those of human C. trachomatis strains, 73% identical to that of Chlamydia pneumoniae IOL-207, 79% identical to that of the C. psittaci guinea pig inclusion conjunctivitis strain, GPIC, and 83% identical to that of the C. psittaci ovine abortion strain S26/3. In contrast, the 6BC sequence was found to be greater than 99% identical to the sequences reported for two strains of C. psittaci, A22/M and Cal-10 meningopneumonitis, believed to be of nonpsittacine avian origin. Monoclonal antibody analysis confirmed the nonpsittacine avian origin of A22/M but identified the Cal-10 strain from which the MOMP gene was previously sequenced as a psittacine strain. These results confirm that psittacine and nonpsittacine avian strains of C. psittaci are closely related and distinct from the mammalian guinea pig inclusion conjunctivitis and ovine abortion strains of C. psittaci. 相似文献
19.
Marguerite Hatch Robert W. Freel N. D. Vaziri 《Pflügers Archiv : European journal of physiology》1993,423(3-4):206-212
In order to characterize oxalate handling by the P2 segment of the rabbit proximal colon, the fluxes of [14C]oxalate, 22Na+, and 36Cl– were measured in vitro using conventional short-circuiting techniques. In standard buffer the proximal colon exhibited net secretion of Na+ (–2.31±0.64 equiv cm–2 h–1), negligible net Cl– transport, and net secretion of oxalate (–12.7±1.6 pmol cm–2 h–1). Replacement of buffer Na+ or Cl– abolished net oxalate secretion, while HCO
3
–
-free media revealed a net absorption of oxalate (19.3±4.2 pmol cm–2 h–1) and stimulated NaCl absorption. Mucosal amiloride and dimethylamiloride (1 mM) significantly reduced the unidirectional fluxes of oxalate and enhanced sodium secretion by decreasing J
ms
Na
. The anion exchange inhibitor 4,4-diisothiocyanatostilbene-2,2-disulfonic acid (DIDS; 0.1 mM, both sides) reduced the unidirectional fluxes of oxalate and chloride. Serosal epinephrine (50 M) stimulated oxalate absorption (21.3±6.3 pmol cm–2 h–1) and sodium absorption (5.71±1.20 equiv cm–2 h–1), whereas dibutyryl-cAMP enhanced oxalate secretion (–43.4±6.9 pmol cm–2 h–1) and stimulated chloride secretion (–7.27 ±0.64 equiv cm–2 h–1). These results indicate that the P2 segment of the proximal colon possesses (a) secretory as well as absorptive capacities, (b) oxalate fluxes that are mediated by pathways involving Na+, Cl–, HCO
3
–
transport and (c) a net oxalate flux that is sensitive to absorptive and secretory stimuli. 相似文献
20.
John P. Hatch Patricia J. Moore Steve Borcherding Margaret Cyr-Provost Nashaat N. Boutros Ermias Seleshi 《Journal of behavioral medicine》1992,15(1):89-112
Thirty-four subjects meeting diagnostic criteria for episodic tension-type headache and 42 who rarely experienced headaches participated in two laboratory sessions in which cephalic electromyographic (EMG) activity, electrodermal activity, heart rate, and finger temperature were recorded. Subjects performed relaxation, choice reaction time, psychomotor tracking, voluntary muscle contraction, and cold pressor tasks. Headache subjects showed significantly greater EMG activity than controls during baseline and stressful task performance. During relaxation, both groups reduced EMG activity from baseline levels, and there was no significant difference in EMG level between the groups during relaxation. Headache subjects reported higher levels of subjective anxiety, depression, anger, and stress than controls. Headache subjects also reported higher levels of pain than controls, and headache subjects reported greater pain during stressful task performance relative to baseline and recovery periods.This research was supported by NIH Grant R01-NS-25114. 相似文献