IFN-γ+874A/T基因多态性与再生障碍性贫血免疫抑制治疗疗效的关系

目的:探讨IFN-γ+874A/T基因多态性与再生障碍性贫血(AA)易感性以及免疫抑制治疗疗效的关系。方法:收集四川大学华西医院血液科确诊的133例汉族AA患者的静脉血标本,其中有62例患者接受免疫抑制治疗且观察期超过4个月,100例汉族健康成人作为对照组。采用PCR、琼脂糖凝胶电泳和DNA测序法检测AA患者和健康对照者IFN-γ基因+874A/T单核苷酸多态性。结果:1AA组中IFN-γ+874 TT基因型频率和T等位基因的分布频率分别为24.8%和48.9%,显著高于健康对照组的7.0%、23.0%(P0.001,P0.001);2 62例AA患者中34例免疫抑制治疗有效,其中携带IFN-γ+874A/T位点TT基因型和T等位基因者的有效率分别为75%及71.4%,显著高于携带AA基因型和A等位基因者的27.3%和41.2%(P=0.008,P=0.001)。结论:IFN-γ+874A/T基因多态性与AA易感性和免疫抑制治疗疗效可能有关。     

Acute Retinal Necrosis Complicating Chickenpox in a Healthy Adult—A Case Report and Review of Literature

Acute retinal necrosis (ARN) is known to occur in conjunction with primary varicella or chickenpox infection. The majority of ARN cases reported in the literature were of milder form with mild to moderate vitritis, limited retinitis, and rare occurrence of retinal breaks or detachment that responded well to intravenous acyclovir, with or without oral prednisolone. We report a case of unilateral ARN with marked vitritis and retinal necrosis leading to retinal breaks following chickenpox in a 32-year-old healthy lady. This patient was successfully treated with intravenous acyclovir followed by oral acyclovir and orbital floor triamcinolone injections to contain the inflammation with barrier laser therapy to secure the retinal breaks with good visual outcome. This case is unusual in its severity, and to our knowledge, orbital floor triamcinolone therapy was not used earlier to contain ARN inflammation.     

Evaluating the Effects of Acupuncture Using a Dental Pain Model in Healthy Subjects – A Randomized,Cross-Over Trial

Acupuncture is a complementary and nonpharmacological intervention that can be effective for the management of chronic pain in addition to or instead of medication. Various animal models for neuropathic pain, inflammatory pain, cancer-related pain, and visceral pain already exist in acupuncture research. We used a newly validated human pain model and examined whether acupuncture can influence experimentally induced dental pain. For this study, we compared the impact of manual acupuncture (real acupuncture), manual stimulation of a needle inserted at nonacupuncture points (sham acupuncture) and no acupuncture on experimentally induced dental pain in 35 healthy men who were randomized to different sequences of all 3 interventions in a within-subject design. BORG CR10 pain ratings and autonomic responses (electrodermal activity and heart rate variability) were investigated. An initial mixed model with repeated measures included preintervention pain ratings and the trial sequence as covariates. The results showed that acupuncture was effective in reducing pain intensity when compared to no acupuncture (β = −.708, P = .002), corresponding to a medium Cohen's d effect size of .56. The comparison to the sham acupuncture revealed no statistically significant difference. No differences in autonomic responses between real and sham acupuncture were found during the intervention procedures.PerspectiveThis study established a dental pain model for acupuncture research and provided evidence that experimentally induced dental pain can be influenced by either real acupuncture or manual stimulation of needles at nonacupuncture points. The data do not support that acupoint specificity is a significant factor in reducing experimental pain.     

Prevalence and Molecular Characterization of Extended-Spectrum-β-Lactamase-Producing Enterobacteriaceae in a Pediatric Patient Population

Very little is known about the prevalence and composition of various types of extended-spectrum β-lactamases (ESBL) in pediatric patients. The aims of this study were the following: (i) to determine the prevalence of ESBLs among Enterobacteriaceae in a tertiary-care pediatric population; (ii) to characterize the genetic composition of the identified ESBL enzymes; and (iii) to determine the relative prevalence of CTX-M enzymes and Escherichia coli ST131 strains among ESBL-producing isolates in the same pediatric patient population. Among the 1,430 Enterobacteriaceae isolates screened for elevated MICs to cefotaxime and/or ceftazidime from pediatric patients during a 1-year period, 94 isolates possessed at least one ESBL gene. CTX-M was the most commonly isolated ESBL type, consisting of 74% of all ESBLs versus 27% TEM and 24% SHV enzymes. Sequence analysis and probe-specific real-time PCR revealed that the majority (80%) of the CTX-M-type ESBLs were CTX-M-15 enzymes, followed by CTX-M-14 (17%) and CTX-M-27(2.8%). Multilocus sequence typing (MLST) and repetitive PCR analyses revealed that the relative prevalence of ST131 among ESBL-producing E. coli isolates is 10.2%. This study highlights the growing problem of ESBL resistance in pediatric Enterobacteriaceae isolates and demonstrates a transition toward the predominance of CTX-M-type enzymes among ESBL-producing Enterobacteriaceae organisms causing pediatric infections.     

A suitable job?: A qualitative study of becoming a nurse in the context of a globalizing profession in India

Background

Research on Indian nurses has focused on their participation as global migrant workers for whom opportunities abroad act as an incentive for many to migrate overseas. However, little is known about the careers of Indian nurses, or the impact of a globalized health care market on nurses who remain and on the profession itself in India.

Objectives

To explore nurses’ accounts of entry into nursing in the context of the globalisation of the nursing profession in India, and the salience of ‘migration’ for nurses’ individual careers.

Design

Qualitative interview study (n = 56).

Settings and participants

The study drew on interviews with 56 nurses from six sites in Bangalore, India. These included two government hospitals, two private hospitals, a Christian mission hospital, a private outpatient clinic and two private nursing colleges. Participants were selected purposively to include nurses from Christian and Hindu backgrounds, a range of home States, ages and seniority and to deliberately over-recruit (rare) male nurses.

Methods

Interviews covered how and why nurses entered nursing, their training and career paths to date, plans for the future, their experiences of providing nursing care and attitudes towards migration. Data analysis drew on grounded theory methods.

Results

Nursing is traditionally seen as a viable career particularly for women from Christian communities in India, where it has created inter-generational ‘nurse families’. In a globalizing India, nursing is becoming a job ‘with prospects’ transcending traditional caste, class and gender boundaries. Almost all nurses interviewed who intended seeking overseas employment envisaged migration as a short term option to satisfy career objectives – increased knowledge, skills and economic rewards – that could result in long-term professional and social status gains ‘back home’ in India. For others, migration was not part of their career plan: yet the increases in status that migration possibilities had brought were crucial to framing nursing as a ‘suitable job’ for a growing number of entrants.

Conclusions

The possibility of migration has facilitated collective social mobility for Indian nurses. Migration possibilities were important not only for those who migrate, but for improving the status of nursing in general in India, making it a more attractive career option for a growing range of recruits.     

Nursing students’ evaluation of clinical learning environment and supervision in a Norwegian hospital placement – A questionnaire survey using CLES+T scale

AimThe clinical learning environment and supervisor-student relationship play vital roles in the learning outcomes of nursing students. The aim of this study is to evaluate nursing students’ experiences with the clinical learning environment and supervision in a hospital placement organised with a dual preceptor team – preceptors holding dual positions both in the clinic and the nursing faculty in addition to the standard one-to-one supervision by a clinical preceptor.DesignThe study is a paper-based survey based on a validated questionnaire developed and tested in hospital settings in various European countries, including Norway.MethodThe Norwegian version of the CLES+T Evaluation Scale, was distributed to all second-year students in three different years (2015–2017) at a nursing faculty.ResultsA total of 61% students (n = 261) returned the questionnaire. Overall, the students considered that their hospital placement provided a good clinical learning environment. The results suggest that the dual preceptor team on top of one-to-one supervision did not interfere negatively with the clinical learning environment Nevertheless, the dual preceptor model did not compensate for a poor relationship with the clinical preceptor. Thus, the association between a reported ‘strained relationship’ with the clinical preceptor and low scores on the CLES+T, reported on by other studies, remained in our data.ConclusionsTo better grasp the complexity in this area, various methods are needed, such as in-depth interviews with students, nurse teachers and clinical preceptors. Further studies need to elaborate on students’ experiences of clinical learning environment according to how supervision is organised.     

PBP1a/LpoA but Not PBP1b/LpoB Are Involved in Regulation of the Major β-Lactamase Gene blaA in Shewanella oneidensis

β-Lactamase production is one of the most important strategies for Gram-negative bacteria to combat β-lactam antibiotics. Studies of the regulation of β-lactamase expression have largely been focused on the class C β-lactamase AmpC, whose induction by β-lactams requires LysR-type regulator AmpR and permease AmpG-dependent peptidoglycan recycling intermediates. In Shewanella, which is ubiquitous in aquatic environments and is a reservoir for antibiotic resistance, production of the class D β-lactamase BlaA confers bacteria with natural resistance to many β-lactams. Expression of the blaA gene in the genus representative Shewanella oneidensis is distinct from the AmpC paradigm because of the lack of an AmpR homologue and the presence of an additional AmpG-independent regulatory pathway. In this study, using transposon mutagenesis, we identify proteins that are involved in blaA regulation. Inactivation of mrcA and lpoA, which encode penicillin binding protein 1a (PBP1a) and its lipoprotein cofactor, LpoA, respectively, drastically enhances blaA expression in the absence of β-lactams. Although PBP1b and its cognate, LpoB, also exist in S. oneidensis, their roles in blaA induction are dispensable. We further show that the mrcA-mediated blaA expression is independent of AmpG.     

Inter‐operator variation in ELISPOT analysis of measles virus‐specific IFN‐γ‐secreting T cells

The ELISPOT assay is a highly sensitive technique used for the detection of individual cytokine releasing cells. We have developed an IFN‐γ ELISPOT assay utilizing unfractionated frozen peripheral blood mononuclear cells (PBMC) to quantify the frequency of measles virus (MV)‐specific IFN‐γ‐secreting T cells in 117 healthy children who had been previously immunized with two doses of the measles‐mumps‐rubella vaccine. We have also estimated the variability associated with the quantification of ELISPOT plates and compared the number of MV‐specific IFN‐γ‐secreting T cells for each subject as determined by two different operators of an ELISPOT reader. The median frequency of MV‐specific IFN‐γ‐producing memory T cells detected by this assay was 0.005 % and 0.01 % as determined by an in‐house and commercial operator, respectively. Although we found a significant correlation (r = 0.83, p<0.0001) between the number of spots counted by the commercial and in‐house operators of an ELISPOT reader, the median number of spots counted by the commercial operator was twice the number of spots counted by an in‐house operator (p<0.001). This demonstrates the importance of using a common ELISPOT reader and operator, among other parameters, to quantify the number of spots when a large volume of plates are being scanned and analyzed.     

Acat1 Knockdown Gene Therapy Decreases Amyloid-β in a Mouse Model of Alzheimer's Disease

Both genetic inactivation and pharmacological inhibition of the cholesteryl ester synthetic enzyme acyl-CoA:cholesterol acyltransferase 1 (ACAT1) have shown benefit in mouse models of Alzheimer''s disease (AD). In this study, we aimed to test the potential therapeutic applications of adeno-associated virus (AAV)-mediated Acat1 gene knockdown in AD mice. We constructed recombinant AAVs expressing artificial microRNA (miRNA) sequences, which targeted Acat1 for knockdown. We demonstrated that our AAVs could infect cultured mouse neurons and glia and effectively knockdown ACAT activity in vitro. We next delivered the AAVs to mouse brains neurosurgically, and demonstrated that Acat1-targeting AAVs could express viral proteins and effectively diminish ACAT activity in vivo, without inducing appreciable inflammation. We delivered the AAVs to the brains of 10-month-old AD mice and analyzed the effects on the AD phenotype at 12 months of age. Acat1-targeting AAV delivered to the brains of AD mice decreased the levels of brain amyloid-β and full-length human amyloid precursor protein (hAPP), to levels similar to complete genetic ablation of Acat1. This study provides support for the potential therapeutic use of Acat1 knockdown gene therapy in AD.     

Single-Dose Comparative Pharmacokinetics of Two Formulations of Lenalidomide 25 mg in Healthy Subjects: A Randomized Crossover Study

Background

Lenalidomide is used for the treatment of multiple myeloma in combination with dexamethasone. The purpose of this study was to compare the pharmacokinetics (PKs) and assess the bioequivalence of two formulations of lenalidomide 25 mg: Lenalid^® 25 mg tablet (test formulation) and Revlimid^® 25 mg capsule (reference formulation).

Methods

A randomized, single-dose, two-treatment, two-period, two-sequence crossover study was conducted in 42 healthy subjects. All subjects were randomly assigned to one of the two sequences, and they received a single dose of test or reference formulation in the first period and the alternative formulation during the next period under fasting conditions. Serial blood samples for PK evaluation were collected up to 24 h post-dose and the PK parameters were estimated by non-compartmental methods. Throughout the study, tolerability was assessed on the basis of adverse events, vital signs, and clinical laboratory tests.

Results

The test formulation showed similar PK profiles to those of the reference formulation. The geometric mean ratio and 90% confidence interval (CI) of the test formulation to the reference formulation for maximum plasma concentration (C_max) was 0.9995 (0.9250–1.0799) and the corresponding value for the area under the concentration–time curve from time zero to time of last quantifiable concentration (AUC_t) was 0.9648 (0.9451–0.9850). Both CIs were within the conventional bioequivalence range of 0.8–1.25. The tolerability profile was not significantly different between the two formulations.

Conclusion

This study found that the PKs of the two formulations of lenalidomide 25 mg were similar and the test formulation met the regulatory criteria for assuming bioequivalence with the reference formulation.

Funding

Samyang Biopharmaceutical Corp.

     

P1A Recombinant β-Lactamase Prevents Emergence of Antimicrobial Resistance in Gut Microflora of Healthy Subjects during Intravenous Administration of Ampicillin

Ipsat P1A is a recombinant β-lactamase which degrades antibiotic residue in the gastrointestinal tract. In an open-label, single-center controlled trial, 36 healthy subjects were randomized to receive (i) ampicillin (1 g intravenously [i.v.] every 6 h [q6h]), (ii) oral P1A recombinant β-lactamase (8.2 mg q6h), or (iii) ampicillin (1 g i.v. q6h) in combination with oral P1A recombinant β-lactamase (8.2 mg q6h) for 5 days. Fecal samples were collected before treatment, during treatment (days 3 to 5), and at follow-up (day 12). The primary end points were (i) changes in gastrointestinal microflora (determined by temperature gradient gel electrophoresis [TGGE]) and (ii) emergence of bacterial resistance (determined by conventional microbiology and PCR of TEM β-lactamase genes). Thirty-five subjects completed the study. The mean similarity percentages of TGGE profiles between baseline and each treatment day sample were significantly lower for the ampicillin group than for the group receiving ampicillin plus P1A recombinant β-lactamase on days 3, 4, and 5 (P < 0.001). Compared with the ampicillin group, subjects receiving ampicillin plus P1A recombinant β-lactamase had significantly fewer ampicillin-resistant coliforms on days 3, 4, and 5 and at follow-up (P ≤ 0.001) and fewer TEM β-lactamase genes on days 3, 4, and 5 (P < 0.02). P1A recombinant β-lactamase was safe and well tolerated. In healthy subjects, P1A recombinant β-lactamase prevents ampicillin-induced alterations in intestinal microflora, emergence of resistance, and the number of TEM genes.The health care system has been impacted greatly by the increasing rates of infection with antibiotic-resistant pathogens (14, 20). Many patients in whom infections occur have previously been exposed to antibiotics, either for prophylaxis or as treatment. While antibiotic treatment can reduce the incidence of infections with certain organisms (prophylactic effect), it may not modify others and can even increase the incidence of infections with some organisms. These effects are attributable to direct antimicrobial activity against the causative organism and/or to effects on competing microflora. The effect on intestinal microflora is of particular interest, as it may lead to selection for bacterial strains resistant to antimicrobial agents, a process that may have particularly severe consequences, resulting in increased mortality, morbidity, and costs (5, 8). Antibiotics that are excreted in high concentrations in bile into the intestinal tract can cause profound disruption of the indigenous microflora (9, 29, 30), resulting in an increased incidence of secondary infections due to acquisition and overgrowth of antimicrobial-resistant pathogens, including vancomycin-resistant enterococci, Candida species, and multiresistant gram-negative bacilli, and also in a number of adverse effects observed in Clostridium difficile infections (1, 2, 6, 8).β-Lactam antibiotics are among the most widely used classes of antimicrobials, and many of these agents are excreted into the intestinal tract in high concentrations. Previous studies have demonstrated that the normal intestinal microflora contains various degrees of antibiotic resistance genes (19, 32, 34) and that healthy individuals may harbor intestinal bacteria that can produce TEM β-lactamases (31, 34). It has further been shown that the resistance patterns of enteric bacteria change in response to increased levels of exposure to antibiotics and that selective pressure from ampicillin treatment can result in increased levels of ampicillin-resistant bacteria (12, 13).The active ingredient of Ipsat P1A capsule is P1A protein. P1A protein is a recombinant class A β-lactamase with a molecular mass of 29 kDa which is capable of hydrolyzing penicillin, aminopenicillins (e.g., ampicillin), and ureidopenicillins (e.g., piperacillin). P1A protein has structural and functional similarities to naturally occurring β-lactamases in the gastrointestinal (GI) microflora. P1A protein is intended for oral use and is presented in a gastroresistant formulation in P1A pellets designed to protect P1A protein from the influence of the acidic gastric medium in the stomach and to start the release of P1A protein in the intestine when the pH exceeds 5.5. This is achieved by using the pH-dependent polymer Eudragit L 30 D-55.In dogs, orally administered P1A recombinant β-lactamase was shown to effectively degrade the GI residue of intravenously administered ampicillin, ampicillin-sulbactam, amoxicillin-clavulanate, and piperacillin-tazobactam (10, 11, 24, 33). Studies using mouse models demonstrated that oral administration of P1A recombinant β-lactamase given in conjunction with ampicillin or piperacillin preserved colonization resistance, reduced antibiotic-associated alteration in the indigenous microflora, and prevented overgrowth of vancomycin-resistant enterococci and Clostridium difficile (35, 36, 37).The aims of this trial with healthy subjects were to evaluate the preventive effect of P1A recombinant β-lactamase on ampicillin-induced changes in GI microflora and the emergence of antimicrobial resistance in intestinal coliforms. The changes in the composition and numbers of selected groups of GI microflora were assessed by culture-based and molecular approaches (temperature gradient gel electrophoresis [TGGE]). Resistance to 10 antimicrobials other than ampicillin was evaluated by determining the susceptibility of coliforms in fecal samples by using the disc diffusion method (CLSI) and quantifying the bla_TEM genes in fecal samples by quantitative PCR. In addition, the safety and tolerability of P1A recombinant β-lactamase were studied.(The results of this study were presented in part at the 15th ECCMID, 2 to 5 April 2005, Copenhagen, Denmark, and at the 45th Interscience Conference on Antimicrobial Agents and Chemotherapy, 16 to 19 December 2005, Washington, DC.)     

Population health as a ‘platform’ for nurse education: A qualitative study of nursing leaders

BackgroundChallenges to the sustainability of global healthcare systems are prompting a shift towards more population-focused models of care. Nurse educators need to develop courses that prepare students for population health practice. However, the educational approaches that can support this shift are poorly understood. Publication of new standards for nurse education by the United Kingdom's (UK) Nursing and Midwifery Council that place greater emphasis on population health presented an opportunity to seek nursing leaders' views on population health in nurse education.ObjectivesTo assess the views of nursing leaders within a Scottish context on the connection between nurse education and population health for all students, evaluate what student nurses need to know to support population health practice, and draw insights from the UK for pre-registration programmes internationally.DesignQualitative interview study.ParticipantsTwenty-four nursing leaders from academic (n = 15), practice (n = 4) and regulatory (n = 5) sectors.MethodsSemi-structured interviews were conducted face-to-face (n = 21), by telephone (n = 2) or Skype (n = 1). Interviews were transcribed and analysed, using interview questions as structural themes, followed by thematic and content analyses.ResultsNursing leaders encouraged rebalancing nurse education towards population health, suggesting that population health concepts should sit at the core of spiral curricula to enable students to (re)view learning through a population health lens. Seven outcomes were identified to equip student nurses for practice in any setting. These formed the mnemonic FULCRUM: Find and interpret evidence; Understand the psychology of behavior and change; Link epidemiology to population health; Consider others and themselves in context; Recognise social determinants of health; Understand the impact of policy and politics on health; Motivate to encourage behaviour change.ConclusionsFULCRUM can guide nurse educators globally to support preparation of graduate nurses for the significant shifts in healthcare delivery and service organisation towards improving population outcomes.     

Epidemiology of Massive Transfusion – A Common Intervention in Need of a Definition

While massive transfusion (MT) recipients account for a small proportion of all transfused patients, they account for approximately 10% of blood products issued. Furthermore, MT events pose organizational and logistical challenges for health care providers, laboratory and transfusion services. Overall, the majority of MT events are to support major bleeding in surgical patients, trauma and gastrointestinal hemorrhage. The clinical context in which the bleeding event occurred, the number of blood products required, patient age and comorbidities are the most important predictors of outcomes for short- and long-term survival. These data are important to inform blood services, clinicians and health care providers in order to improve care and outcomes for patients with major bleeding. There is no standard accepted definition of MT, with most definitions based on number of blood components administered within a certain time-period or activation of MT protocol. The type of definition used has implications for the clinical characteristics of MT recipients included in epidemiological and interventional studies. In order to understand trends in incidence of MT, variation in blood utilization and patient outcomes, and to harmonize research outcomes, a standard and universally accepted definition of MT is urgently required.     

Effects of a Self–micro-emulsifying Delivery System Formulation Versus a Standard ω-3 Acid Ethyl Ester Product on the Bioavailability of Eicosapentaenoic Acid and Docosahexaenoic Acid: A Study in Healthy Men and Women in a Fasted State

Purpose

Intakes of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are associated with several potential health benefits, but standard ethyl ester (EE) formulations of these ω-3 fatty acids require the co-ingestion of fat for adequate absorption. The objective of this research was to assess the relative bioavailability of EPA and DHA administered in a proprietary self–micro-emulsifying delivery system (SMEDS) formulation compared with EPA and DHA in a standard ω-3 acid EE product in healthy men and women in a fasted state.

Population structure of Enterococcus faecium causing bacteremia in a Spanish university hospital: setting the scene for a future increase in vancomycin resistance?

Over an 8-year period (1995 to 2002), 86 Enterococcus faecium blood isolates from 84 patients, of which 54 were ampicillin resistant (AREF) and 32 were ampicillin susceptible (ASEF), were studied in a university hospital (1,200 beds; serving a population of 600,000) in Spain, a country characterized by a near-absence of resistance to vancomycin and very high rates of ampicillin resistance among enterococci. Clonal relatedness by pulsed-field gel electrophoresis (PFGE), antibiotic susceptibility, presence of the virulence/epidemicity genes esp(Efm) and hyl(Efm), and identification of purK alleles were studied. A group of isolates was also analyzed by amplified fragment length polymorphism (AFLP) and multilocus sequence typing. Medical charts (30 variables collected) were reviewed for 60/84 patients. ASEF showed high clonal diversity (32 PFGE types, 11 purK alleles, 4 AFLP genogroups), did not harbor putative virulence genes, and had no specific association with hospital acquisition. AREF isolates belonged to a clonal complex (CC) of genetically related strains (purK-1, AFLP genogroup C), occasionally harboring putative virulence traits, and were from patients with particular risk factors. Within this CC, previously associated with vancomycin-resistant E. faecium isolates causing outbreaks worldwide (W. L. Homan et al., J. Clin. Microbiol. 40:1963-1971, 2002), a great genetic diversity of antibiotic resistance and virulence/epidemicity profiles was found. Associations between esp and a >7-day hospital stay and between purK-1, hospital location, and nosocomial acquisition were noted (P < 0.001). These findings reflect the importance of local environmental differences in the evolution of this CC, suggesting that the emergence of vancomycin resistance among AREF strains in Spain may be a question of time.     

A Case of Guillain-Barré Syndrome in a Primary Care Setting

Guillain-Barré Syndrome (GBS) is an immune-mediated peripheral neuropathy characterized by rapidly progressive symmetrical ascending weakness and sensory loss. The disease can progress rapidly and be fatal if diagnosis and treatment interventions are delayed. In most patients, the neuropathic symptoms are preceded by an antecedent infection. The patient may present with initial symptoms of upper respiratory tract infection or gastroenteritis. This article presents a case report of GBS, followed by a detailed discussion of the pathophysiology, diagnostic studies, differential diagnosis, types, prognosis, and management of patients with this condition.