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101.

Purpose

Diagnosing idiopathic intracranial hypertension (IIH), or pseudotumor cerebri, can be challenging in children. Diagnosis is based on lumbar puncture, opening pressures, and appearance of the optic disk. Misdiagnosis of papilledema, a typical finding, may lead to unnecessary treatments and procedures. We report 52 children over a 6-year period to better identify the true incidence of pseudopapilledema and other factors that may confound the diagnosis of IIH.

Methods

A retrospective chart review approved by the Institutional Review Board was performed. Fifty-two children under the age of 21 referred to us based on suspected IIH or papilledema from 2007 to 2013 are included in this study. Patients were assessed by a pediatric ophthalmologist and a neurosurgeon.

Results

Fifty-two children were initially diagnosed with IIH and/or papilledema; 26 diagnoses were revised to pseudopapilledema after pediatric ophthalmological review. Out of those 26 patients with pseudopapilledema, 14 had undergone lumbar punctures, 19 had MRIs, 9 had CTs, and 12 were taking medications—these medications were discontinued upon revision of the diagnoses. The difference in the CSF opening pressure between children diagnosed with true IIH (32.7 cm H2O) and children diagnosed with pseudopapilledema (24.7 cm H2O) was statistically significant.

Conclusions

IIH diagnosis is heavily reliant on the appearance of the optic disk. Pediatric ophthalmological assessment is essential to carefully examine the optic disk and prevent further unnecessary investigation and treatments. Close communication between pediatricians, ophthalmologists, and neurosurgeons can avoid invasive procedures for children who do have pseudopapilledema, and not IIH or associated papilledema.  相似文献   
102.
103.
Pertussis has shown a striking resurgence in the United States, with a return to record numbers of reported cases as last observed in the 1950s. Bordetella pertussis isolates lacking pertactin, a key antigen component of the acellular pertussis vaccine, have been observed, suggesting that B. pertussis is losing pertactin in response to vaccine immunity. Screening of 1,300 isolates from outbreak and surveillance studies (historical isolates collected from 1935 up to 2009, isolates from the 2010 California pertussis outbreak, U.S. isolates from routine surveillance between 2010-2012, and isolates from the 2012 Washington pertussis outbreak) by conventional PCR and later by Western blotting and prn sequencing analyses ultimately identified 306 pertactin-deficient isolates. Of these pertactin-deficient strains, 276 were identified as having an IS481 in the prn gene (prnIS481 positive). The first prnIS481-positive isolate was found in 1994, and the next prnIS481-positive isolates were not detected until 2010. The prevalence of pertactin-deficient isolates increased substantially to more than 50% of collected isolates in 2012. Sequence analysis of pertactin-deficient isolates revealed various types of mutations in the prn gene, including two deletions, single nucleotide substitutions resulting in a stop codon, an inversion in the promoter, and a single nucleotide insertion resulting in a frameshift mutation. All but one mutation type were found in prn2 alleles. CDC 013 was a predominant pulsed-field gel electrophoresis (PFGE) profile in the pertactin-positive isolates (203/994) but was found in only 5% (16/306) of the pertactin-deficient isolates. Interestingly, PFGE profiles CDC 002 and CDC 237 represented 55% (167/306) of the identified pertactin-deficient isolates. These results indicate that there has been a recent dramatic increase in pertactin-deficient B. pertussis isolates throughout the United States.  相似文献   
104.
OBJECTIVE: To compare intraoperative complications of exteriorized and in situ uterine repair during elective cesarean delivery under spinal anesthesia. METHODS: This study was a randomized, single-blinded trial in 80 women undergoing elective cesarean delivery under spinal anesthesia. Patients were randomly assigned to exteriorized or in situ uterine repair. Obstetricians were asked to perform assisted delivery of the placenta. Spinal anesthesia and oxytocin management were standardized. Phenylephrine was used to maintain systolic blood pressure within 10% of the baseline. The primary outcome was intraoperative, postdelivery nausea or vomiting. RESULTS: Postdelivery nausea or vomiting (18% compared with 38%; P=.04) and tachycardia (3% compared with 18%; P=.03) were significantly reduced in the in situ group compared with the exteriorized group. The duration of uterine repair was significantly shorter in the exteriorized group (median 10 minutes [first and third quartiles 9, 13], compared with 11 minutes [9, 15]) (P=.04). The duration of surgery (36 minutes [30, 41] compared with 37 minutes [30, 45]) and estimated blood loss (mean+/-standard deviation 625+/-489 mL compared with 653+/-416 mL) were similar between the in situ and the exteriorized groups. There was no correlation between duration of uterine repair and estimated blood loss. CONCLUSION: Exteriorization of the uterus for repair is associated with an increased incidence of nausea and vomiting and tachycardia during cesarean delivery under spinal anesthesia. Uterine repair should be done in situ where possible. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00452972 LEVEL OF EVIDENCE: I.  相似文献   
105.
Chlamydia is now the most common notifiable infectious disease in many countries, a fact that has serious ramifications for the reproductive health of women. This review highlights the epidemiology, pathophysiology, clinical features and reproductive sequelae of the infection. Current screening and management methods are outlined. Obstetricians and gynaecologists are ideally placed to play a major role in the primary prevention of this significant sexually transmitted infection.  相似文献   
106.
Background: Engaging and inspiring the next generation of physician-scientists at an early stage is recognised as key to ensure the future of medical research. However, little is known about medical student perceptions of research.

Objectives: We attempted to ascertain perceptions of research and research-orientated careers from medical students studying in different countries.

Methods: An online questionnaire was developed, piloted, and promoted to medical students in various countries.

Results: 1625 responses were collected from 38 countries. Analysis was restricted to data collected from countries with >100 responses (n?=?890). Less than half the respondents felt their medical school provided adequate research training. Key perceived barriers to research participation as a student included lack of time and difficulty finding mentors or projects. A significant gender disparity existed in research ambitions of students with females desiring less research involvement. The importance of barriers and satisfaction with research training differed significantly between countries.

Conclusions: Students perceive a number of key barriers to research involvement and pursuit of research-orientated careers. Programmes designed to engage students with research should focus on overcoming identified barriers. Greater effort is needed to engage female students who report more significant barriers and less desire to follow research-orientated careers.  相似文献   
107.
108.
ObjectiveTo describe the restructuring of services by British radiologists in response to evolving national guidelines and highlight the impact of the COVID-19 pandemic on the treatment of musculoskeletal (MSK) conditions.MethodsAn online anonymised survey was distributed via the British Society of Skeletal Radiology (BSSR) members forum in November 2020. Responses were collated using a standardised Google form including 21 questions.Results135 members of the BSSR completed the survey. 85% of respondents stopped performing corticosteroid injections (CSI) during the initial lockdown of the pandemic. This was primarily influenced by national guidelines. The majority of respondents initially abstained from offered CSI procedures, then by November 2020, 69% of respondents were providing CSI for high and low risk patients, 23% were only providing CSI for low-risk patients with 8% still not performing any CSI. 40% of respondents reported routinely obtaining specific written consent regarding the risk of COVID-19. Approximately, 11,000 CSI were performed by respondents between March and November 2020 with no reported significant COVID-19-related complications. Over 80% of BSSR members reported that the number of CSI procedures that they performed dropped by more than 80% compared to usual. 73% of respondents reported an increased backlog of patients awaiting treatment. The average waiting time for routine outpatient CSI treatment was > 12 weeks in 53% of responses, compared to 34% the previous year.ConclusionThe COVID-19 pandemic has had a significant impact on the clinical practices of MSK radiologists in the UK. Our survey highlights the rapid response of BSSR members as national guidelines evolved. Currently, the majority of respondents are performing CSI for musculoskeletal conditions when clinically indicated, with enhanced consent. However, the pandemic has resulted in increased waiting times – delaying the treatment of patients who may be suffering with significant pain and disability. Further research is warranted to provide guidance around both service recovery and provision of CSI around COVID-19 vaccination schedules.Advances in knowledgeBSSR members responded rapidly to changing guidelines during the COVID-19 pandemic. The majority of respondents are currently performing CSI when clinically indicated. The pandemic has resulted in a significant increase in waiting times which will have a significant impact on UK musculoskeletal services.  相似文献   
109.
Neuroplasticity has classically been understood to arise through changes in synaptic strength or synaptic connectivity. A newly discovered form of neuroplasticity, neurotransmitter switching, involves changes in neurotransmitter identity. Chronic exposure to different photoperiods alters the number of dopamine (tyrosine hydroxylase, TH+) and somatostatin (SST+) neurons in the paraventricular nucleus (PaVN) of the hypothalamus of adult rats and results in discrete behavioral changes. Here, we investigate whether photoperiod-induced neurotransmitter switching persists during aging and whether epigenetic mechanisms of histone acetylation and DNA methylation may contribute to this neurotransmitter plasticity. We show that this plasticity in rats is robust at 1 and at 3 months but reduced in TH+ neurons at 12 months and completely abolished in both TH+ and SST+ neurons by 18 months. De novo expression of DNMT3a catalyzing DNA methylation and anti-AcetylH3 assessing histone 3 acetylation were observed following short-day photoperiod exposure in both TH+ and SST+ neurons at 1 and 3 months while an overall increase in DNMT3a in SST+ neurons paralleled neuroplasticity reduction at 12 and 18 months. Histone acetylation increased in TH+ neurons and decreased in SST+ neurons following short-day exposure at 3 months while the total number of anti-AcetylH3+ PaVN neurons remained constant. Reciprocal histone acetylation in TH+ and SST+ neurons indicates the importance of studying epigenetic regulation at the circuit level for identified cell phenotypes. The findings may be useful for developing approaches for noninvasive treatment of disorders characterized by neurotransmitter dysfunction.  相似文献   
110.
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