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101.
The purpose of this study is to determine the effectiveness of fetal fibronectin (FFN) compared to assessment of cervical dilation (CD) in clinical management of women with symptomatic preterm labor (PTL). Pregnant women presenting to Thomas Jefferson University Hospital between May 1, 2001 and November 30, 2002 with symptomatic PTL underwent FFN sampling and had a complete clinical evaluation including a pelvic bimanual examination. Inclusion criteria were singleton pregnancy, gestational age (GA) between 24 (0) and 33 (6) weeks, CD < 3 cm, and intact amniotic membranes. FFN samples were sent out and results were available within 4-12 hours. Clinical management including tocolysis, antenatal steroids, and hospitalization was determined based on digital CD assessment and FFN status. A dilated cervix was defined as CD > 1 cm. Ninety-three patients were included. Spontaneous preterm delivery (SPTD) at < 37 weeks occurred in 20 of 93 (21.5%) patients. Medical therapy use was significantly higher in patients with dilated cervix than in those with a closed cervix (all P values < 0.05). Tocolysis and steroid use in FFN-negative patients and FFN-positive patients were not significantly different. Furthermore, tocolytic use was higher in FFN-negative patients than in women with positive FFN (50% versus 42.1%; P = 0.53). Use of antenatal steroids was similar in patients with CD >/= 1 cm and a positive FFN (54.5% versus 47.4%; P = 0.92). Compared with FFN-negative patients, women with closed cervix were less likely to undergo interventions. In symptomatic PTL patients, CD determined clinical management more than FFN status. Overall, the use of FFN was not effective in decreasing "unnecessary" clinical interventions.  相似文献   
102.
Introduction:Most of the molybdenum (Mo) is used in metallurgical applications, the tetrathiomolybdate form is an experimental chelating agent for Wilson’s disease. Human data of acute Mo exposure are lacking and, no report of no-observed-adverse-effect level (NOAEL) has been described until now.Case study:We report a case of acute occupational exposure to molybdenum, with the related plasma and urine molybdenum concentrations, caused by an accidental ingestion of a sip of an anti-corrosion liquid for metal containing sodium molybdate. Our purpose was to evaluate potential systemic toxicity of molybdenum and to evaluate the dose-response/dose-effect relationship. We estimated the amount of ingested molybdenum to make a mg/kg relationship and performed repeated urine and plasma molybdenum determinations. The patient was hospitalized for three days to monitor possible development of acute symptoms/biochemical alterations.Discussion:We estimated the amount of the sip around 50 ml, with an estimation of a total of 5 gr of sodium molybdate that, for the patient bodyweight of 80 kg, would mean 62,5 mg/kg of ingested Mo. Blood and urine samples collected 2 hours after ingestion showed 50 mcg/L (reference range: 0.43 – 1.8 mcg/L) and 630 mcg/L (refence range: up to 116 mcg/L) of Mo respectively, confirming acute exposure. The patients remained asymptomatic confirming that an estimated oral dose of Mo of 62.5 mg/kg was not associated with adverse effects.Conclusions:Our value, being extrapolated by a single case, will require further confirmations from other studies to allow a full evaluation of a NOAEL. Nevertheless, it does not preclude its use in evaluating the probable absence of adverse effect in the context of acute Mo exposure.  相似文献   
103.
104.
Nitric oxide (NO) contributes to maintaining normal cardiovascular and renal function. This bioactive signalling molecule is generally formed enzymatically by NO synthase in the vascular endothelium. NO bioactivity can also be attributed to dietary intake of inorganic nitrate, which is abundant in our diet, especially in green leafy vegetables and beets. Ingested nitrate is reduced to nitrite by oral commensal bacteria and further to NO systemically. Previous studies have shown that dialysis, by means of removing nitrate and nitrite from the body, can reduce NO bioactivity. Hence, dietary intervention approaches aimed to boost the nitrate–nitrite–NO pathway may be of benefit in dialysis patients. The purpose of this study was to examine the kinetics of plasma nitrate and nitrite after a single intake of nitrate-rich concentrated beetroot juice (BJ) in adult hemodialysis (HD) patients and in age-matched healthy volunteers (HV). Eight HD patients and seven HV participated in this single center, randomized, single-blind, placebo-controlled, crossover study. Each participant received a sequential single administration of active BJ (70 mL, 400 mg nitrate) and placebo BJ (70 mL, 0 mg nitrate) in a random order separated by a washout period of seven days. For the kinetic analysis, blood samples were collected at different time-points before and up to 44 h after BJ intake. Compared with placebo, active BJ significantly increased plasma nitrate and nitrite levels both in HD patients and HV. The area under the curve and the maximal concentration of plasma nitrate, but not of nitrite, were significantly higher in HD patients as compared with HV. In both groups, active BJ ingestion did not affect blood pressure or plasma potassium levels. Both BJs were well tolerated in all participants with no adverse events reported. Our data provide useful information in planning dietary nitrate supplementation efficacy studies in patients with reduced NO bioactivity.  相似文献   
105.
The first-generation COVID-19 vaccines have been effective in mitigating severe illness and hospitalization, but recurring waves of infections are associated with the emergence of SARS-CoV-2 variants that display progressive abilities to evade antibodies, leading to diminished vaccine effectiveness. The lack of clarity on the extent to which vaccine-elicited mucosal or systemic memory T cells protect against such antibody-evasive SARS-CoV-2 variants remains a critical knowledge gap in our quest for broadly protective vaccines. Using adjuvanted spike protein–based vaccines that elicit potent T cell responses, we assessed whether systemic or lung-resident CD4 and CD8 T cells protected against SARS-CoV-2 variants in the presence or absence of virus-neutralizing antibodies. We found that 1) mucosal or parenteral immunization led to effective viral control and protected against lung pathology with or without neutralizing antibodies, 2) protection afforded by mucosal memory CD8 T cells was largely redundant in the presence of antibodies that effectively neutralized the challenge virus, and 3) “unhelped” mucosal memory CD8 T cells provided no protection against the homologous SARS-CoV-2 without CD4 T cells and neutralizing antibodies. Significantly, however, in the absence of detectable virus-neutralizing antibodies, systemic or lung-resident memory CD4 and “helped” CD8 T cells provided effective protection against the relatively antibody-resistant B1.351 (β) variant, without lung immunopathology. Thus, induction of systemic and mucosal memory T cells directed against conserved epitopes might be an effective strategy to protect against SARS-CoV-2 variants that evade neutralizing antibodies. Mechanistic insights from this work have significant implications in the development of T cell–targeted immunomodulation or broadly protective SARS-CoV-2 vaccines.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has continued to exert devastating impacts on the human life, with >280 million infections and over 5.4 million deaths to date. Although there are millions of convalescent people with some measure of immunity and 8.8 billion doses of vaccine administered to date, further threats of widespread severe COVID-19 disease looms heavily as immunity induced by infection or the first-generation vaccines may not provide effective and durable protection, either due to waning immunity or due to poor antibody cross-reactivity to new variants (15).It is clear that virus-neutralizing antibodies provide the most effective protection to SARS-CoV-2, following vaccination or recovery from infection (6). However, T cell–based protection against SARS-CoV-2 has become a central focus because T cells recognize short amino acid sequences that can be conserved across viral variants (79). Indeed, T cells in convalescent COVID-19 patients have shown robust responses that are directed at multiple viral proteins, and depletion of these T cells delayed SARS-CoV-2 control in mice (1012). These data suggest a protective role for T cells in COVID-19 infection. In effect, what constitutes an effective, an ineffective, or a perilous T cell response to SARS-CoV-2 in lungs remains poorly defined. Controlled studies in laboratory animals are of critical importance to elucidate the role and nature of T cells in lungs during SARS-CoV-2 virus infection and in protective immunity.Based on the differentiation state, anatomical localization and traffic patterns, memory T cells are classified into effector memory (TEM), central memory (TCM), and tissue-resident memory (TRM) (13, 14). There is accumulating evidence that airway/lung-resident TRMs, and not migratory memory T cells (TEMs) are critical for protective immunity to respiratory mucosal infections with viruses, such as influenza A virus (IAV) and respiratory syncytial virus (1521). Development of TRMs from effector T cells in the respiratory tract requires local antigen recognition and exposure to critical factors, such as transforming growth factor (TGF)-β and interleukin (IL)-15 (15). Therefore, mucosal vaccines are more likely to elicit TRMs in lungs than parenteral vaccines (22, 23). A subset of effector T cells in airways of COVID-19 patients display TRM-like features (24), but the development of TRMs or their importance in protective immunity to reinfection are yet to be determined. Furthermore, all SARS-CoV-2 vaccines in use are administered parenterally and less likely to induce lung TRMs. While depletion of CD8 T cells compromised protection against COVID-19 in vaccinated rhesus macaques (25), the relative effectiveness of vaccine-induced systemic/migratory CD8 T cell memory vs. lung/airway TRMs in protective immunity to COVID-19 is yet to be defined.In this study, using the K18-hACE2 transgenic (tg) mouse model of SARS-CoV-2 infection, we have interrogated two key aspects of T cell immunity: 1) the requirements for lung-resident vs. migratory T cell memory in vaccine-induced immunity to SARS-CoV-2; and 2) the role of lung-resident memory CD4 vs. CD8 T cells in protection against viral variants in the presence or absence of virus-neutralizing antibodies. Studies of mucosal versus systemic T cell–based vaccine immunity using a subunit protein-based adjuvant system that elicits neutralizing antibodies and T cell immunity, demonstrated that: 1) both mucosal and parenteral vaccinations provide effective immunity to SARS-CoV-2 variants; 2) CD4 T cell–dependent immune mechanisms exert primacy in protection against homologous SARS-CoV-2 strain; and 3) the development of spike (S) protein-specific “unhelped” memory CD8 T cells in the respiratory mucosa are insufficient to protect against a lethal challenge with the homologous Washington (WA) strain of SARS-CoV-2. Unexpectedly, we found that systemic or mucosal lung-resident memory CD4 and “helped” CD8 T cells engendered effective immunity to the South African B1.351 β-variant in the apparent absence of detectable mucosal or circulating virus-neutralizing antibodies. Taken together, mechanistic insights from this study have advanced our understanding of viral pathogenesis and might drive rational development of next-generation broadly protective SARS-CoV-2 vaccines that induce humoral and T cell memory.  相似文献   
106.
107.
<正>To the Editor:Ischemia-reperfusion injury following surgery and transplantation can lead to irreversible multiorgan failure.Intracellular calcium overload is associated to cellular death during ischemiareperfusion.A recently discovered heparin fragment (HF),trisulfated disaccharide (TD),that acts on sodium-calcium exchanger(NCX) decreasing intracellular Ca2+,showed effectiveness on protecting hepatocytes from ischemia-reperfusion injury [1],  相似文献   
108.
The Short-Alcohol Dependence Data (SADD) and the Alcohol Dependence Scale (ADS) questionnaires, both designed to evaluate the degree of severity of alcohol dependence, were compared in a sample of 201 known alcoholics. Although a significant correlation was found between the scores obtained on the two scales (r = 0.61; P less than 0.01), respondents were classified differently by the two questionnaires (Kappa = 0.20). Subjects were generally considered less dependent by the ADS than by the SADD. Different possibilities that could explain the differential classification are discussed.  相似文献   
109.
Behavioral studies found evidence for superior cognitive empathy (CE) in pedophilic men without a history of child sexual offending (P − CSO) compared to pedophilic men with a history of child sexual offending (P + CSO). Functional magnetic resonance imaging (fMRI) studies also point to differences between P − CSO and P + CSO. Neural processing associated with CE has not yet been investigated. Therefore, the present study aimed to explore the neural correlates of CE in subjects with pedophilia with (P + CSO) and without (P − CSO) child sexual offending. 15 P + CSO, 15 P − CSO and 24 teleiophilic male controls (TC) performed a CE task during fMRI. We observed reduced activation in the left precuneus (Pcu) and increased activation in the left anterior cingulate cortex (ACC) in P − CSO compared to P + CSO. P − CSO also showed stronger connectivity between these regions, which might reflect a top-down modulation of the Pcu by the ACC toward an increased self-focused emotional reaction in social situations. There was also evidence for increased right superior temporal gyrus activation in P − CSO that might constitute a potentially compensatory recruitment due to the dampened Pcu activation. These findings provide first evidence for altered neural processing of CE in P − CSO and underline the importance of addressing CE in pedophilia and CSO in order to uncover processes relevant to effective prevention of child sexual abuse.  相似文献   
110.
Low-dimensional structures, such as nanotubes, have been the focus of research interest for approximately three decades due to their potential for use in numerous applications in engineering and technology. In addition to extensive investigation of carbon nanotubes, those composed of elements other than carbon, the so-called non-carbon nanotubes, have also begun to be studied, since they can be more suitable for electronic and optical nano-devices than their carbon counterparts. As in the case of carbon nanotubes, theoretical (numerical and analytical) approaches have been established predominantly to study non-carbon nanotubes. So far, most of work has dealt with the investigation of the structural and electrical properties of non-carbon nanotubes, paying less attention to the evaluation of their mechanical properties. As the understanding of the mechanical behaviour of the constituents is fundamental to ensure the effective performance of nanotube-based devices, this overview aims to analyse and systematize the literature results on the elastic properties of inorganic non-carbon nanotubes.  相似文献   
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