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21.
22.
Polysomnographic and actigraphic evidence of sleep fragmentation in patients with irritable bowel syndrome 总被引:3,自引:0,他引:3
STUDY OBJECTIVE: To characterize the function and quality of sleep in patients with irritable bowel syndrome (IBS). DESIGN: A prospective study with a historic comparison group. SETTING: A regional hospital that also serves as a tertiary referral center. PATIENTS: Eighteen patients with IBS and a comparison group of 20 matched adults with mild benign snoring. INTERVENTIONS: A polysomnography study and a wrist actigraphy study. MEASUREMENTS: All subjects underwent sleep studies and completed self-report questionnaires (IBS severity, psychosocial variables, sleep function, and Epworth Sleepiness Scale). Fourteen IBS and 11 comparison patients underwent actigraphy. RESULTS: The IBS patients had more than 70% less slow-wave stage sleep (4.5 +/- 7.3% vs 19.3 +/- 12.9%; P = 0.006), compensated by increased stage 2 sleep (72.2 +/- 6.6% vs 60.1 +/- 16.8%; P = 0.01). The IBS group had significant sleep fragmentation with a significantly higher arousal and awakening index (P < 0.001), a longer wake period after sleep onset (P = 0.02), and more downward shifts to lighter sleep stages (P = 0.01). The 4-night actigraphy study supported the polysomnography findings. The sleep fragmentation index was significantly higher (P = 0.008) in the IBS group. The IBS patients reported greater daytime sleepiness (9.0 +/- 4.8 vs 6.4 +/- 4.8, Epworth Sleepiness Scale score, P < 0.01) and greater impairment in quality of life, which correlated significantly with the sleep fragmentation indexes. The difference between the groups was not due to differences in baseline anxiety/depression levels. CONCLUSIONS: Patients with IBS have impaired sleep quality, reduced slow-wave sleep activity, and significant sleep fragmentation. The cause-and-effect relationship of these findings with patients' daytime symptoms should be studied further. 相似文献
23.
Mahadevan MM; McIntosh Q; Miller MM; Breckinridge SM; Maris M; Moutos DM 《Human reproduction (Oxford, England)》1998,13(4):979-982
Cryopreservation of human zygotes and embryos has been routinely performed
by in-vitro fertilization clinics for many years. Karran and Legge (1996)
first reported that formaldehyde (FA) present in the cryoprotective
solutions can have a deleterious effect on mouse oocytes. FA is a
cytotoxic, carcinogenic and mutagenic chemical. The effect of FA on mouse
zygotes was investigated. In addition, the concentrations of FA in
propanediol (PROH) obtained from various sources were determined. Pooled
1-cell embryos were dispensed into droplets of modified Ham's F10 or human
tubal fluid containing various concentrations of FA. Since bovine serum
albumin (BSA) may minimize toxicity additional trials were done as above in
the absence of BSA. FA concentration in the standard 1.5 M PROH, from
different sources in water, was measured in the same assay using a standard
curve of 0-100 microM FA. FA in a complex medium had a significant
deleterious effect on embryo development and hatching but only at 1 mM
concentration (P < 0.000001; see Tables I-III). There was no significant
effect of FA at 100 microM. However, in a simple medium even 50 microM FA
decreased embryo hatching. FA was present in 1.5 M PROH from different
sources (range 1.0-35.3 microM concentration). It appears that FA
concentrations do not increase with storage because FA concentrations were
low even after opening and storage for 3 years on the shelf. This suggests
that FA is a contaminant during the manufacturing process and may vary from
manufacturer to manufacturer and batch to batch. Until further studies are
done to confirm the lack of toxicity to embryos during cryopreservation
(with or without FA scavengers) it may be prudent to screen all batches of
cryoprotectants for FA as part of quality control.
相似文献
24.
High throughput parallel analysis of hundreds of patient samples for more than 100 mutations in multiple disease genes 总被引:5,自引:0,他引:5
Shuber AP; Michalowsky LA; Nass GS; Skoletsky J; Hire LM; Kotsopoulos SK; Phipps MF; Barberio DM; Klinger KW 《Human molecular genetics》1997,6(3):337-347
As more mutations are identified in genes of known sequence, there is a
crucial need in the areas of medical genetics and genome analysis for
rapid, accurate and cost-effective methods of mutation detection. We have
developed a multiplex allele-specific diagnostic assay (MASDA) for analysis
of large numbers of samples (> 500) simultaneously for a large number of
known mutations (> 100) in a single assay. MASDA utilizes
oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA
samples are immobilized on a solid support and a single hybridization is
performed with a pool of allele-specific oligonucleotide (ASO) probes. Any
probes complementary to specific mutations present in a given sample are in
effect affinity purified from the pool by the target DNA. Sequence-specific
band patterns (fingerprints), generated by chemical or enzymatic sequencing
of the bound ASO(s), easily identify the specific mutation(s). Using this
design, in a single diagnostic assay, we tested samples for 66 cystic
fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell
anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations,
four mutations in Canavan disease, four mutations in Fanconi anemia, and
five mutations in BRCA1. Each mutation was correctly identified. Finally,
in a blinded study of 106 of these mutations in > 500 patients, all
mutations were properly identified. There were no false positives or false
negatives. The MASDA assay is capable of detecting point mutations as well
as small insertion or deletion mutations. This technology is amenable to
automation and is suitable for immediate utilization for high-throughput
genetic diagnostics in clinical and research laboratories.
相似文献
25.
Oocyte morphology predicts outcome of intracytoplasmic sperm injection 总被引:10,自引:14,他引:10
Serhal PF; Ranieri DM; Kinis A; Marchant S; Davies M; Khadum IM 《Human reproduction (Oxford, England)》1997,12(6):1267-1270
To examine the influence of cytoplasmic morphology on the success rate of
intracytoplasmic sperm injection (ICSI), the morphology of 837 metaphase II
oocytes was assessed after cumulus stripping. The main abnormalities
detected were excessive granularity, cytoplasmic inclusions such as
vacuoles, smooth endoplasmic reticulum clustering and refractile bodies.
Microinjection was performed in 538 oocytes with normal cytoplasm, 142 out
of 161 with excessive granularity and 112 out of 138 with cytoplasmic
inclusions. Very poor oocytes were not injected. No difference was found in
fertilization rate. The embryos achieved cleaved normally and a similar
number of good quality embryos among the three groups was noted. The
outcome of transfer of embryos derived solely from normal oocytes (group A:
72 patients, 183 embryos) was compared with those from oocytes with
cytoplasmic abnormalities (group B: 34 patients, 85 embryos). In group A,
17 clinical pregnancies (24% per patient, implantation rate 10%) were
established. In group B, only one clinical pregnancy (3% per patient,
implantation rate 1%) was established, from the transfer of embryos derived
from oocytes with homogeneous granularity of the cytoplasm. No pregnancy
resulted following the transfer of embryos from eggs with cytoplasmic
inclusions. The difference was statistically significant. The outcome of
ICSI is dependent on the quality of the oocytes retrieved. Normal
fertilization and early embryo development were achieved in oocytes with
abnormal cytoplasm morphology, but the resulting embryos failed to
demonstrate the same implantation potential as those derived from oocytes
with normal cytoplasm.
相似文献
26.
Simultaneous isolation of simian foamy virus and HTLV-III/LAV from chimpanzee lymphocytes following HTLV-III or LAV inoculation 总被引:9,自引:0,他引:9
27.
28.
Summary The phenotype of pathogenicity by direct intracerebral inoculation of herpes simplex virus type 1 (HSV-1) was mapped in the viral genome. This phenotype could be rescued by cotransfection of unit length HSV-1 DNA of an avirulent strain with the BamHI fragment L (0.70–0.738 map units) cloned from a virulent strain. The virulence function was localized in the 2.0 Kb NruI-BamHI fragment in the right-hand side of BamHI-L, the same region that encodes a virus cell-fusion gene (3). Transduction of virulence was linked with the phenotype of a larger plaque size. It is concluded that a neurovirulence function resides in the BamHI-L fragment of the HSV-1 genome, closely linked to the viral gene for cell fusion. 相似文献
29.
Airway reactivity in children is often assessed using a histamine inhalation challenge test. The bronchoconstrictor agents are usually delivered by five slow inspiratory capacity (IC) maneuvers, the IC method. We compared the IC method with a tidal breathing (TB) method in 30 children; 11 were normal, six were under investigation for asthma and 13 were known asthmatics. None of the normal children responded to either method, whereas 18 out of the 19 (95%) known or suspected asthmatics responded to the TB method while only 13 out of 19 (68%) showed a significant reduction in FEV1 when the IC method was used. The concentration of histamine necessary to cause a 20% reduction in FEV1 was less for the TB method, suggesting that in children the TB method will produce airway reactivity more quickly than the IC method. 相似文献
30.