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41.

Background

Direct brain stimulation via electrodes implanted for intracranial electroencephalography (iEEG) permits the modulation of endogenous electrical signals with significantly greater spatial and temporal specificity than non-invasive approaches. It also allows for the stimulation of deep brain structures important to memory, such as the hippocampus, that are difficult, if not impossible, to target non-invasively. Direct stimulation studies of these deep memory structures, though, have produced mixed results, with some reporting improvement, some impairment, and others, no consistent changes.

Objective/hypothesis

We hypothesize that to modulate cognitive function using brain stimulation, it is essential to modulate connected nodes comprising a network, rather than just alter local activity.

Methods

iEEG data collected while patients performed a spatiotemporal memory retrieval task were used to map frequency-specific, coherent oscillatory activity between different brain regions associated with successful memory retrieval. We used these to identify two target nodes that exhibited selectively stronger coupling for spatial vs. temporal retrieval. In a subsequent session, electrical stimulation - theta-bursts with a fixed phase-lag (0° or 180°) – was applied to the two target regions while patients performed spatiotemporal retrieval.

Results

Stimulation selectively impaired spatial retrieval while not affecting temporal retrieval, and this selective impairment was associated with theta decoupling of the spatial retrieval network.

Conclusion

These findings suggest that stimulating tightly connected nodes in a functional network at the appropriate phase-lag may effectively modulate the network function, and while in this case it impaired memory processes, it sets a foundation for further network-based perturbation studies.  相似文献   
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43.
在英国,1/3以上的人有患癌症的危险,癌症在人们死因中排第2位,65%的癌症病人年龄在65岁以上。机体的任何部位都可能发生癌症,并可经血液、淋巴系统转移。癌症的类型有200多种。病因与基因类型和环境的变化密切相关。运动可以减少患癌风险和延缓病情进展。运动与癌症发生的风险规律的运动和健康的饮食是保持身体健康和适宜体重的最好方式。这有助于降低妇女患子宫癌,绝经期患乳腺癌的机率,还有助于防止发生肠癌和肾癌。一般认为中等量运动为每周5 d,每次为30min左右。中等量运动是指快走、游泳、在有坡的路面骑自行车、跳舞、修整花园、家务…  相似文献   
44.

Objectives

To evaluate the CINtec® PLUS assay (mtm laboratories), a new immunocytochemical method for the simultaneous detection of p16INK4a and Ki-67, in liquid-based cervico-vaginal cytology, investigating the association of the dual staining with HPV infection and genotyping as well as cytological and histological abnormalities.

Methods

140 women with a cervico-vaginal sample obtained immediately before the colposcopy were enrolled. This cytological sample was used for HPV testing with the Linear Array HPV Genotyping Test, the dual staining with the CINtec® PLUS kit and the morphology assessment.

Results

Cytology results were 38 NILM, 16 ASC-US, 32L-SIL, 54H-SIL or worse. 113 patients also had a colposcopy-guided biopsy, classified as 14 negative, 35 CIN1, 24 CIN2, 37 CIN3, 3 invasive SCC. A strong association between p16/Ki-67 and HR-HPV infection was found (COR = 6.86, 95% CI: 1.84-31.14). Importantly, the association between p16/Ki-67 positivity and HPV16 and/or 18 infection was 2-fold stronger compared to that with the infection by other HR-HPV types (COR = 9.92, 95% CI: 2.39-47.77 vs COR = 4.20, 95% CI: 0.99-20.87). In addition, p16/Ki-67 positivity rate significantly increased with the severity of the cytological and histological abnormalities (p < 0.05 in both cases). p16/Ki-67 positivity resulted strongly associated with a CIN2 + diagnosis (COR = 10.86 95% CI: 4.16-29.12).

Conclusions

This preliminary study evidenced that p16/Ki-67 immunostaining might have a relevant clinical role, since the dual staining was significantly associated with HR-HPV infection, particularly with HPV 16 and 18, and the increasing grade of the cervical lesions, the positivity for this biomarker being strongly related to the presence of a CIN2 + lesion.  相似文献   
45.
Background Lower limb venous ulceration ranks among the 10 most common medical problems in Western countries and has significant socioeconomic impact. The aim of this study was to identify the risk factors for unhealed, recurrent, and large ulcers and to characterize patients with active or recently healed venous ulcers. Methods We identified 97 patients and assessed 103 ulcerated limbs in 90 patients. All patients underwent clinical examination, arterial and venous system evaluation, ankle‐brachial index determination, and ultrasound of the affected limb. Clinical characteristics included age, gender, race, ulcer duration, time since first episode, history of recurrence, localization of ulcer, ulcer area, eczema, ochre dermatitis, lipodermatosclerosis, pain, body mass index, and medical history data. Risk factors were identified by univariate analysis and estimated odds ratios. Results We assessed 90 patients (103 limbs) with active or healed venous leg ulcers, of whom 84.4% were Caucasian and 68.9% were female. Mean age was 56.0 ± 13.3 years. Ulcers had remained unhealed for <1 year in 40.7%. Lipodermatosclerosis, lower limb hyperpigmentation, edema, and eczema were seen in 96.7%, 95.6%, 94.4%, and 51.1% of patients, respectively. Pain was a frequent symptom in 74.4%. Body mass index was assessed in 85 patients: 30.6% were slightly, 36.5% moderately, and 7% severely obese. Patient age >60 years (odds ratio [OR] 4.0), extensive lipodermatosclerosis (OR 8.7), and previous history of ulceration (OR 19.9) were risk factors for unhealed ulcers. Time since first ulcer episode ≥2 years (OR 29.2) and incompetence of venous systems (OR 1.6) were risk factors for recurrence. Conclusions Longstanding and large ulcers and recurrences are the main problems encountered by venous ulcer patients. Severe lipodermatosclerosis, previous ulcer history, and time since first ulcer episode ≥2 years are significant risk factors.  相似文献   
46.

Purpose

The authors evaluated the usefulness of three-dimensional rotational angiography (3DRA) in surgical planning and postoperative evaluation of cerebral aneurysms.

Materials and methods

A total of 111 consecutive aneurysms in 100 patients (32 emergency referrals due to haemorrhage) were evaluated with 3DRA over a period of 3 years. The rotational study was always performed with a single injection of 20 cc of contrast agent in the afferent vessel after diagnostic cerebral angiography in the two orthogonal projections. Three-dimensional reconstructions were obtained for the pre- and postoperative assessment.

Results

Three-dimensional RA provides a virtual view of the surgical field with the same orientation required for the surgical approach and, compared with surgical findings, reliably defined location, orientation, morphology and relationship with parent vessels of the aneurysm in all cases. Postoperatively, it allowed better assessment of any residual lesion and of the relationship between surgical clips and parent vessels, compared with standard 2D angiography.

Conclusions

3DRA is a reliable method for preliminary assessment of cerebral aneurysms undergoing surgery. It provides multiple projections with a preview of the surgical field and study of lesion characteristics, which can help achieve faster and safer surgery. Compared with 2D angiography, the 3D model, with its multiple views, allows better assessment of postoperative outcomes. The method also significantly reduces the number of angiographic projections and therefore radiation and contrast-medium dose to the patient.  相似文献   
47.
Background and aimsHemiplegic migraine (HM) is a rare form of migraine characterized by the presence of a motor and other types of aura. HM can be sporadic or familial. Familial hemiplegic migraine (FHM) is an autosomal dominant disorder, classified into 3 subtypes, based on the gene involved (CACNA1A in FHM1, ATP1A2 in FHM2 and SCN1A in FHM3). The clinical presentation is highly heterogeneous and some attacks may be severe.We report the clinical characteristics and genetic analysis of 12 patients belonging to a family with CACNA1A-p.Thr501Met gene mutation.MethodsWe screened for mutations in CACNA1A gene 15 patients belonging to the same family. The exonic sequences of CACNA1A were analyzed using a Tru-seq® Custom Amplicon (TSCA) (Illumina Inc., San Diego, CA) targeted capture and paired end library kit. Sanger sequencing was used to confirm CACNA1A variants and segregation analysis.ResultsCACNA1A-p.Thr501Met mutation was found in 12 of the 15 patients screened, which was compatible with the diagnosis of FHM1.Attacks of hemiplegic migraine were reported by 10 of the 12 subjects (83.33%). Only one subject developed persistent mild cerebellar symptoms and none of the subjects developed cerebellar atrophy.DiscussionThe variant p.Thr501Met was described previously in association with episodic ataxia and rarely with FHM related to cerebellar symptoms. FHM1 has a broad clinical spectrum and about half of the families have cerebellar involvement. In our study, only one patient developed persistent cerebellar deficits.These data suggest that CACNA1A-p.Thr501Met mutation can occur prevalently as hemiplegic migraine.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10194-021-01297-5.  相似文献   
48.
The evaluation of sister chromatid exchanges (SCE) is used to establish the cytogenic damage in subjects exposed to toxic substances. The test is considered to be 1 of the most sensitive and accurate indicators of damage and responds to toxic chemicals at low doses. We evaluated the incidence of SCE in peripheral lymphocytes of patients with articular prostheses. Subjects with prostheses made of titanium-aluminium-vanadium alloys presented a significantly higher SCE number than the control population (6.3+/-2.3 vs 4.4+/-1.3; P = .0128), whereas subjects with prostheses made of chrome-cobalt alloy or mixed prostheses presented a higher SCE value than the controls but not significantly different. The presence of high-frequency cells was alarming only in 5 patients, 4 of whom had titanium alloy prostheses, whereas none belonged to the control group. The number of SCE was not affected by the presence of bone-cement used in prosthesis fixation or by the implant duration. The indication of possible cytogenic damage in patients with titanium alloy prostheses that emerged from this study should be considered carefully, even though the sample population was small.  相似文献   
49.
AIM: Usually measles is not severe, but serious complications can occur and thus hospitalization is needed. The aim of this study was to assess the reasons of hospitalizations of the persons affected by measles and the severity of disease as a result of measles infection. METHODS: During an outbreak from 2002 to 2003 in the province of Taranto, 73 hospitalized persons affected by measles were evaluated. RESULTS: The age of the 73 hospitalized patients ranged between 1 and 42 years old (median age 14.5 years). An hospitalizations rate of 63% was reported in the first 4 months of 2003. Measles-related complications were observed in 35.6% of cases. In 14 cases (19%) we observed a pneumonia with a concomitant myocardititis and pancreatitis in 2 cases. Postmeasles encephalitis was diagnosed in 7 cases (9.5%). In 2 cases a concomitant myelitis occurred, with the presence of sequelae at the time of discharge but none permanent. Measles related appendicitis was observed in 5 males (6.8%) and appendectomy was performed in all cases. Data analysis showed that the patients with an age <15 years old had a higher risk of complications than patients with an age > or =15 years. None death was reported. CONCLUSIONS: At present, measles and its related complications continue to be a serious illness even in industrialized countries, only a complete immunization vaccine strategy could permit measles' eradication.  相似文献   
50.
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