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1.

Objective

This study assessed the association between the timing of first epinephrine administration (EA) and the neurological outcomes following out-of-hospital cardiac arrests (OHCAs) with both initial shockable and non-shockable rhythms.

Methods

This was a post-hoc analysis of a multicenter prospective cohort study (SOS-KANTO 2012), which registered OHCA patients in the Kanto region of Japan from January 2012 to March 2013. We included consecutive adult OHCA patients who received epinephrine. The primary result included 1-month favorable neurological outcomes defined as cerebral performance category (CPC) 1 or 2. Secondary results included 1-month survival and return of spontaneous circulation (ROSC) after arrival at the hospital. Multivariable logistic regression analysis determined the association between delay per minute of the time from call to first EA in both pre- or in-hospital settings and outcomes.

Results

Of the 16,452 patients, 9344 were eligible for our analyses. In univariable analysis, the delay in EA was associated with decreased favorable neurological outcomes only when the initial rhythm was a non-shockable rhythm. In multivariable analyses, delay in EA was associated with decreased ROSC (adjusted odds ratio [OR] for one minute delay, 0.97; 95% confidence interval [CI], 0.96–0.98) and 1-month survival (adjusted OR, 0.95; 95% CI, 0.92–0.97) when the initial rhythm was a non-shockable rhythm, whereas during a shockable rhythm, delay in EA was not associated with decreased ROSC and 1-month survival.

Conclusions

While assessing the effectiveness of epinephrine for OHCA, we should consider the time-limited effects of epinephrine. Additionally, consideration of early EA based on the pathophysiology is needed.  相似文献   
2.
Skin tumors were produced on the back of hairless mice, HOS (HR/De), by exposure to ultraviolet B light (UVB, 290–320 nm) with 4 different protocols. The first tumors appeared earlier (in 10 weeks in group I and 7 weeks in group III) when initial intense exposure was given, followed by repeated lower-level exposures, than when the mice were exposed to the repeated UV only (in 16 weeks both in group II and group IV). All mice developed skin tumors earlier in the groups given the repeated UV exposures three times a week than in the groups given the exposures twice a week. Most of the skin tumors produced by the UVB exposure were histologically malignant, being transplantable to nude mice, and the cultured cells grown from the tumors were capable of producing tumors when injected into nude mice. The accelerated development of skin tumors by initial intense exposure and short intervals of repeated exposure observed in this study may have implications for humans who expose themselves to intense sunbathing and UV tanning (burning) by fluorescent sun lamps.  相似文献   
3.
The purpose of the present study was to investigate the effects of informational and motivational level of feedback stimuli on the stimulus-preceding negativity (SPN). In the time estimation task, in which a visual stimulus was presented 3 s after a voluntary movement, (a) the information level (high information and low information) and (b) the motivation level (reward and no-reward) for feedback stimuli were manipulated. Under the high-information condition, subjects received feedback information about (1) correctness (correct or incorrect), (2) direction of error (under- or overestimate), and (3) degree of accuracy (accurate or less accurate) of their time estimation. In the low-information condition, however, they received information about the correctness only. In the reward condition, they received a monetary reward for accurate time estimations but received nothing in the no-reward condition. The results demonstrated a significant interaction of information by motivation level, showing that the SPN amplitude under the reward/high-information was larger than that in the no-reward/high-information condition. The results are discussed in terms of emotional anticipation, taking into consideration the result of self-report that subjects felt to be more motivated when they received precise information.  相似文献   
4.
We have examined whether the tumour suppressor p53 protein suppressedUV-induced mutations in the hypoxathine-guanine phosphoribosyltransferase (HPRT) gene and in the supF gene of the shuttlevector plasmid pMY189. We used human osteosarcoma Saos-LP12cells, in which wild type (wt) p53 protein was induced by treatmentwith isopopyl-(ß-D-thiogalactopyranoside. The inductionof wt p53 protein suppressed UV-induced mutations but not spontaneousmutations in the HPRT gene. The frequency of UV-induced mutationsinduced by UV-irradiation of the plasmid was also significantlylower in cells with induced wt p53 protein than in the uninducedcells. In addition, we found that frequency of G : C to A :T transition mutations which occurred at the 3' base pair ofdipyrimidine sites were significantly lower in the cells withinduced wt p53 protein than in the uninduced cells. These findingssuggestthat wt p53 protein may play roles in modulating DNArepair pathway, resulting in the suppression of UV-induced mutations. 1To whom correspondence should be addressed  相似文献   
5.
Silver‐Russell syndrome (SRS) is characterized by prenatal and postnatal growth retardation with morphologic anomalies. Maternal uniparental disomy 7 has been reported in some SRS patients. PEG1/MEST is an imprinted gene on chromosome 7q32 that is expressed only from the paternal allele and is a candidate gene for SRS. To clarify its biological function and role in SRS, we screened PEG1/MEST abnormalities in 15 SRS patients from various standpoints. In the lymphocytes of SRS patients, no aberrant expression patterns of two splice variants (α and β) of PEG1/MEST were detected when they were compared with normal samples. Direct sequence analysis failed to detect any mutations in the PEG1/MEST α coding region, and there were no significant mutations in the 5′‐flanking upstream region containing the predicted promoter and the highly conserved human/mouse genomic region. Differential methylation patterns of the CpG island for PEG1/MEST α were normally maintained and resulted in the same pattern as in the normal control, suggesting that there was no loss of imprinting. These findings suggest that PEG1/MEST can be excluded as a major determinant of SRS. © 2001 Wiley‐Liss, Inc.  相似文献   
6.
A simple method for the preparation of the inner liposomes for double liposomes (DL) was developed. The encapsulation efficiency of erythrosine in liposomes prepared by this new method is superior to that of the previous method because of the concentration of the drug in the lipid membrane. To evaluate the usefulness of DL prepared by the glass‐filter method modified in this study as an oral dosage form of salmon calcitonin (SCT), a suspension of liposomes containing SCT was administered to rats at a dose of 10 μg SCT/kg. Each type of DL showed better efficacy than its inner liposomes alone. The decrease in plasma calcium level was dependent on the electrical charge and particle size of the inner liposomes. The hypocalcemic efficacy of DL encapsulating SCT‐loading cationic liposomes relative to that after subcutaneous administration of SCT at a dose of 1 μg/kg was 6.47%, which was the largest value obtained. These results indicated that not only the particle size but also the electrical charge of inner liposomes affect intestinal absorption. This study verified that the efficacy was increased because of the decrease in diameter of the inner liposomes and the use of lipid with a positive charge. These findings concluded that DL might be useful as an oral dosage form of SCT. Drug Dev. Res. 58:253–257, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   
7.
8.
BACKGROUND/AIMS: Histamine H2 receptor antagonists are considered to exert their effects on gastric acid secretion more rapidly than proton pump antagonists. However, there are no reports concerning the direct interaction of a histamine H2 receptor antagonist with the human H2 receptor in terms of onset of action. This study aims to characterize how rapidly famotidine and ranitidine, the most widely used histamine H2 receptor antagonists, interact with the human histamine H2 receptor. METHODS: HEK293 cell lines, stably expressing human histamine H2 receptors, were obtained. The dose- and time-dependent effects of famotidine and ranitidine on [3H]-tiotidine binding and histamine-stimulated cAMP production were analyzed. RESULTS: Ranitidine inhibited both [3H]-tiotidine binding and histamine-stimulated cAMP production more promptly than did famotidine. Inhibition of histamine-stimulated cAMP production by Cmax doses of famotidine (20 mg p.o.) and ranitidine (150 mg p.o.) peaked by 15 and 2 min, respectively. [3H]-tiotidine binding was not saturated by 60 min at the famotidine Cmax, while the ranitidine Cmax had produced saturation by 15 min. CONCLUSION: Ranitidine inhibits the human histamine H2 receptor very rapidly.  相似文献   
9.

Objectives

Acute alcohol intoxication is often treated in emergency departments by intravenous crystalloid fluid (IVF), but it is not clear that this shortens the time to achieving sobriety. The study aim was to investigate the association of IVF infusion and length of stay in the ED.

Methods

This single-center retrospective cohort study was conducted in Japan and included patients aged ≥ 20 years of age and treated for acute alcohol intoxication without or with IVF. The primary outcome was the length of the ED stay and the treatments were compared by time-to-event analysis.

Results

A total of 106 patients, 42 treated without IVF and 64 with IVF. The baseline characteristics of the two groups were similar. Kaplan–Meier analysis and the generalized Wilcoxon test found no significant difference between the two treatments in the time to ED discharge. The median time was 189 (IQR 160–230) minutes without IVF and 254.5 (203–267 minutes with IVF; p = 0.052). A Cox proportional hazards regression model adjusted for potential confounding variables found that patients treated with IVF were less likely to be discharged earlier than those treated without IVF (HR 0.54, 95% CI: 0.35–0.84, p = 0.006).

Conclusions

IVF for treatment of acute alcoholic intoxication prolonged ED length of stay even after adjustment for potential confounders. Patients given IVF for acute alcohol intoxication should be selected with care.  相似文献   
10.
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