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1.
Toxoplasma gondii (T. gondii) is the cause of toxoplasmosis. Primary infection in an immunocompetent person is usually asymptomatic. Serological surveys demonstrate that world-wide exposure to T. gondii is high (30% in US and 50–80% in Europe). Vertical transmission from a recently infected pregnant woman to her fetus may lead to congenital toxoplasmosis. The risk of such transmission increases as primary maternal infection occurs later in pregnancy. However, consequences for the fetus are more severe with transmission closer to conception. The timing of maternal primary infection is, therefore, critically linked to the clinical manifestations of the infection. Fetal infection may result in natural abortion. Often, no apparent symptoms are observed at birth and complications develop only later in life. The laboratory methods of assessing fetal risk of T. gondii infection are serology and direct tests.Screening programs for women at childbearing age or of the newborn, as well as education of the public regarding infection prevention, proved to be cost-effective and reduce the rate of infection.The impact of antiparasytic therapy on vertical transmission from mother to fetus is still controversial. However, specific therapy is recommended to be initiated as soon as infection is diagnosed.  相似文献   
2.
BackgroundAs the coronavirus disease 2019 (COVID-19) pandemic continues, there are concerns regarding waning immunity and the emergence of viral variants. The immunogenicity of Ad26.COV2.S against wild-type (WT) and variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) needs to be evaluated.MethodThis prospective cohort study was conducted between June 2021 and January 2022 at two university hospitals in South Korea. Healthy adults who were scheduled to be vaccinated with Ad26.COV2.S were enrolled in this study. The main outcomes included anti-spike (S) IgG antibody and neutralizing antibody responses, S-specific T-cell responses (interferon-γ enzyme-linked immunospot assay), solicited adverse events (AEs), and serious AEs.ResultsFifty participants aged ≥ 19 years were included in the study. Geometric mean titers (GMTs) of anti-S IgG were 0.4 U/mL at baseline, 5.2 ± 3.0 U/mL at 3–4 weeks, 55.7 ± 2.4 U/mL at 5–8 weeks, and 81.3 ± 2.5 U/mL at 10–12 weeks after vaccination. GMTs of 50% neutralizing dilution (ND50) against WT SARS-CoV-2 were 164.6 ± 4.6 at 3-4 weeks, 313.9 ± 3.6 at 5–8 weeks, and 124.4 ± 2.6 at 10–12 weeks after vaccination. As for the S-specific T-cell responses, the median number of spot-forming units/106 peripheral blood mononuclear cell was 25.0 (5.0–29.2) at baseline, 60.0 (23.3–178.3) at 5-8 weeks, and 35.0 (13.3–71.7) at 10–12 weeks after vaccination. Compared to WT SARS-CoV-2, ND50 against Delta and Omicron variants was attenuated by 3.6-fold and 8.2-fold, respectively. The most frequent AE was injection site pain (82%), followed by myalgia (80%), fatigue (70%), and fever (50%). Most AEs were grade 1–2, and resolved within two days.ConclusionSingle-dose Ad26.COV2.S was safe and immunogenic. NAb titer and S-specific T-cell immunity peak at 5–8 weeks and rather decrease at 10–12 weeks after vaccination. Cross-reactive neutralizing activity against the Omicron variant was negligible.  相似文献   
3.
BackgroundNumerous patients around the globe are dying from coronavirus disease 2019 (COVID-19). While age is a known risk factor, risk analysis in the young generation is lacking. The present study aimed to evaluate the clinical features and mortality risk factors in younger patients (≤ 50 years) with a critical case of COVID-19 in comparison with those among older patients (> 50 years) in Korea.MethodsWe analyzed the data of adult patients only in critical condition (requiring high flow nasal cannula oxygen therapy or higher respiratory support) hospitalized with PCR-confirmed COVID-19 at 11 hospitals in Korea from July 1, 2021 to November 30, 2021 when the delta variant was a dominant strain. Patients’ electronic medical records were reviewed to identify clinical characteristics.ResultsDuring the study period, 448 patients were enrolled. One hundred and forty-two were aged 50 years or younger (the younger group), while 306 were above 50 years of age (the older group). The most common pre-existing conditions in the younger group were diabetes mellitus and hypertension, and 69.7% of the patients had a body mass index (BMI) > 25 kg/m2. Of 142 younger patients, 31 of 142 patients (21.8%, 19 women) did not have these pre-existing conditions. The overall case fatality rate among severity cases was 21.0%, and it differed according to age: 5.6% (n = 8/142) in the younger group, 28.1% in the older group, and 38% in the ≥ 65 years group. Age (odds ratio [OR], 7.902; 95% confidence interval [CI], 2.754–18.181), mechanical ventilation therapy (OR, 17.233; 95% CI, 8.439–35.192), highest creatinine > 1.5 mg/dL (OR, 17.631; 95% CI, 8.321–37.357), and combined blood stream infection (OR, 7.092; 95% CI, 1.061–18.181) were identified as independent predictors of mortality in total patients. Similar patterns were observed in age-specific analyses, but most results were statistically insignificant in multivariate analysis due to the low number of deaths in the younger group. The full vaccination rate was very low among study population (13.6%), and only three patients were fully vaccinated, with none of the patients who died having been fully vaccinated in the younger group. Seven of eight patients who died had a pre-existing condition or were obese (BMI > 25 kg/m2), and the one remaining patient died from a secondary infection.ConclusionAbout 22% of the patients in the young critical group did not have an underlying disease or obesity, but the rate of obesity (BMI > 25 kg/m2) was high, with a fatality rate of 5.6%. The full vaccination rate was extremely low compared to the general population of the same age group, showing that non-vaccination has a grave impact on the progression of COVID-19 to a critical condition. The findings of this study highlight the need for measures to prevent critical progression of COVID-19, such as vaccinations and targeting young adults especially having risk factors.  相似文献   
4.
Auditory brain stem evoked potentials (ABEPs) were recorded from 10 adults and 10 children who where neurologically and audiometrically normal. ABEPs were recorded in response to 75 dB HL clicks presented at rates of 10/sec and 50/sec. Normative values were calculated for amplitude and latency, as well as for inter-peak amplitude ratio and a variety of inter-peak latency differences and interaural differences at the two stimulus presentation rates. Normative values of the effect of increasing stimulus rate were calculated as well. Measures of changes in ABEPs between stimulus rates of 50/sec and 10/sec were the only derived measures that were significantly different between our adult and child normal populations. In addition, 50 patients with various conditions affecting the brain stem were examined. Increasing stimulus presentation rate had a significant effect on detection of abnormality in ABEPs from the patients examined. Measures of changes in ABEPs between stimulus rates of 50/sec and 10/sec seemed to be sensitive to a subset of abnormalities in our patient population. The case histories of the patients indicate that the subset may be impaired synaptic function. Measures of the effect of rate on ABEPs may complement the traditional measures that are primarily sensitive to white matter lesions.  相似文献   
5.
A case of a 10 year old boy who underwent a T10 continuous thoracic paravertebral block (TPVB) using a standard technique for postoperative pain management is reported. In the postoperative recovery area, 10 mL of Omnipaque contrast dye was injected through the catheter and an anteroposterior chest radiograph was performed. The radiograph showed longitudinal spread of contrast parallel to the spine from the T4-T5 intervertebral disc to the T10-T11 intervertebral disc with clear lateral extension of contrast along the fifth through the tenth intercostal nerves.  相似文献   
6.
J Ben-David  D P Zipes 《Circulation》1990,82(1):225-233
In 84 open-chest dogs, we studied the effects on early afterdepolarizations (EADs) and ventricular tachyarrhythmias (VTs) induced by cesium chloride (168 mg/kg i.v.) of alpha-adrenoceptor stimulation with phenylephrine (100 micrograms plus 0.25 microgram/kg/min i.v.) and with left ansa subclavia stimulation (LAS; 2 Hz, 4 msec, 2 mA) after propranolol (0.5 mg/kg) administration. We also studied the effects of alpha-adrenoceptor blockade with phentolamine (3 mg/kg), prazosin (25-500 micrograms/kg), yohimbine (10-500 micrograms/kg), WB 4101 (2 mg/kg), and benoxathian (2 mg/kg) during decentralized LAS. EAD amplitude, presented as a percentage of monophasic action potential amplitude, was recorded simultaneously with contact electrodes from the right and left ventricular endocardium. Phenylephrine and LAS plus propranolol increased EAD amplitude (31.5 +/- 8.8% to 47.8 +/- 9.7% and 34.8 +/- 4.1% to 46.1 +/- 6.4%, respectively) and the prevalence of VT (from three to nine of 11 dogs and from the three to five of six dogs, respectively). Prazosin produced a dose-response decrease in EAD amplitude and reduced the prevalence of VT. Yohimbine did not alter the amplitude of EADs or the prevalence of VT. WB 4101 and phentolamine reduced the amplitude of EADs produced by cesium and LAS (from 44.3 +/- 10.2% to 32.6 +/- 9.4% and from 39.8 +/- 6.9% to 30.3 +/- 6.3%, respectively) and the prevalence of VT (from eight to one of 10 dogs and from 13 to 5 of 20 dogs, respectively). Benoxathian did not alter significantly the amplitude of EADs (41.6 +/- 11.4% to 37.5 +/- 9.4%) or the prevalence of VT (from six to five of 10 dogs).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
OBJECTIVES. The purpose of this study was to test the hypothesis that the longer duration of ventricular action potentials in hypertrophied hearts predisposes to the development of early after-depolarizations and triggered ventricular tachyarrhythmias. BACKGROUND. For unknown reasons, the incidence of sudden death is greater in patients with myocardial hypertrophy. METHODS. We measured left ventricular monophasic action potentials in normal dogs and dogs with left ventricular hypertrophy before and after administration of the calcium agonist BAY K 8644 and the potassium channel blocker cesium. RESULTS. We demonstrated longer action potential durations in dogs with than in those without left ventricular hypertrophy. Also, BAY K 8644 produced phase 2 early afterdepolarizations and ventricular tachyarrhythmias more frequently in the dogs with than in those without left ventricular hypertrophy. Phenylephrine, an alpha agonist, further increased the action potential duration in hypertrophied hearts and the propensity to develop early afterdepolarizations and ventricular tachyarrhythmia after administration of BAY K 8644. Control and hypertrophied hearts developed early afterdepolarizations and ventricular tachyarrhythmia equally when exposed to cesium. CONCLUSIONS. Although in vitro studies have shown that fibers of hypertrophied ventricular myocardium can develop triggered activity as a result of both early and late afterdepolarizations, the present study is the first to show in vivo that the hypertrophied ventricular myocardium compared with the normal ventricle is predisposed to develop phase 2 early afterdepolarizations that appear to trigger ventricular tachyarrhythmia. It is possible that such a mechanism contributes to the development of ventricular tachyarrhythmia and sudden cardiac death in patients with left ventricular hypertrophy. If this is shown to be true, specific pharmacologic interventions can be suggested.  相似文献   
8.
Fifty-one successive patients treated with intravenous streptokinase 1.7 +/- 0.8 (mean +/- SD) hours after onset of symptoms of acute myocardial infarction were evaluated during a three-month posthospital follow-up period. Coronary angiography was performed four to nine days after the initial hospital admission. Twenty-eight patients had a second late angiogram. Forty-one patients had successful reperfusion but only 25% of all patients were without significant clinical cardiovascular manifestations during this period. Postmyocardial infarction angina pectoris occurred in 21 patients, an abnormal stress test result was present in 28 patients, eight patients developed congestive heart failure, and five patients had reinfarction. An intervention with percutaneous transluminal coronary angioplasty or coronary artery bypass graft was performed in 15 (37%) of 41 reperfused patients. A significantly higher intervention rate was present in patients treated with streptokinase within one hour following the onset of symptoms. Early reocclusion (within three months of the infarct) was noted in patients with 60% or more residual stenosis in their infarct-related coronary artery. These patients also had a significantly greater incidence of angina pectoris. Our findings indicate that early thrombolytic therapy of acute myocardial infarction preserves myocardium, and since the infarct-related artery is patent, but narrowed, the jeopardized area is responsible for a high-risk syndrome with an increased likelihood of ischemic symptoms. An early aggressive approach may be indicated, especially for patients with greater than 60% residual stenosis in their infarct-related coronary artery.  相似文献   
9.
Clinical Oral Investigations - The effect of leucocyte- and platelet-rich fibrin (L-PRF), associated with DBBM (deproteinized bovine bone mineral; Bio-Oss®) was investigated and compared with...  相似文献   
10.
This pioneering study focuses on differences in self-monitoring between normative youth and youth at-risk for deviant behavior. Self-monitoring is a personality trait for the ability to change behavior in response to different situations. Self-monitoring, and especially sensitivity to the expressive behavior of others (SEB), plays an important role in identity formation, in social adjustment of adolescents to normative or deviant peer groups, and in the development of deviant behavior. The participants included 328 normative and at-risk youth from three age groups. They completed the Juvenile Delinquency Self-Report Questionnaire and the Adolescence Self-Monitoring Scale. A significant difference was found in the level of deviant behavior, where at-risk youth reported higher participation in deviant behavior compared to normative youth. One of the factors of self-monitoring, SEB, was higher among normative than among at-risk youth. An increase in SEB was observed with increasing age. Furthermore, the females’ self-monitoring was higher than that of the males.  相似文献   
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