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Experimental studies emphasize the importance of homeostatic plasticity as a mean of stabilizing the properties of neural circuits. In the present work we combined two techniques able to produce short-term (5-Hz repetitive transcranial magnetic stimulation, rTMS) and long-term (transcranial direct current stimulation, tDCS) effects on corticospinal excitability to evaluate whether and how the effects of 5-Hz rTMS can be tuned by tDCS preconditioning. Twelve healthy subjects participated in the study. Brief trains of 5-Hz rTMS were applied to the primary motor cortex at an intensity of 120% of the resting motor threshold, with recording of the electromyograph traces evoked by each stimulus of the train from the contralateral abductor pollicis brevis muscle. This interventional protocol was preconditioned by 15 min of anodal or cathodal tDCS delivered at 1.5 mA intensity. Our results showed that motor-evoked potentials (MEPs) increased significantly in size during trains of 5-Hz rTMS in the absence of tDCS preconditioning. After facilitatory preconditioning with anodal tDCS, 5-Hz rTMS failed to produce progressive MEP facilitation. Conversely, when 5-Hz rTMS was preceded by inhibitory cathodal tDCS, MEP facilitation was not abolished. These findings may give insight into the mechanisms of homeostatic plasticity in the human cerebral cortex, suggesting also more suitable applications of tDCS in a clinical setting.  相似文献   
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Matrix metalloproteinases, in particular the gelatinases MMP-2 and MMP-9, have received great attention in recent years as putative tumour markers for clinical applications. The main reason for the observed interest is their easy detection in body fluids. Moreover, recent evidence has shown multiple functions of MMPs, rather than simply degrading ECM, which include the mobilisation of growth factors and processing of surface molecules. Several authors have reported increased levels of MMPs in a number of cancers, but clinical correlations in breast cancer are still fragmentary. Thus, the aim of the present research was to investigate the activity levels of circulating gelatinases in the sera of breast cancer patients by means of zymographic analysis, and correlate data with clinicopathological parameters. In all, 80 patients and 22 healthy volunteers were involved in this study. Sera were obtained prior to surgery. The clinical variables were: grading of tumours, tumour size, lymph node involvement, tumour staging, oestrogen and progesterone receptor levels (76 out of 80 cases), and c-erbB-2 levels (46 cases). The densitometric measures of MMP-2 and MMP-9 activity levels indicated that the average values of both gelatinase activities were significantly higher in breast cancers than in control sera (P<0.0001). In addition, our analysis showed for the first time that elevated activity levels of both gelatinases correlated only with c-erbB-2 overexpression (P=0.0273 for MMP-2 and P=0.0075 for MMP-9). An inverse correlation was observed with regard to oestrogen receptor expression (P=0.0075 for MMP-2 and P=0.0273 for MMP-9). Moreover, a borderline inverse correlation was observed between the activity levels of both enzymes and nuclear grade (P=0.0511 for MMP-2 and P=0.0794 for MMP-9). In conclusion, the present data suggest that serum measures of MMP's activity may have diagnostic value for discriminating subgroups of breast cancer patients and support the hypothesis that ERBB2 amplification and/or overexpression enhance signalling pathways that may lead to increased production of gelatinases in c-erbB-2 positive breast cancers with higher metastatic potentialities.  相似文献   
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Background & Aims

Chronic infection with hepatitis B and C viruses (HBV & HCV) is a major contributor to liver disease and liver-related mortality in Uzbekistan. There is a need to demonstrate the feasibility of large-scale simplified testing and treatment to implement a national viral hepatitis elimination program.

Methods

Thirteen polyclinics were utilized to screen, conduct follow-up biochemical measures and treat chronic HBV and HCV infection in the general adult population. Task shifting and motivational interviewing training allowed nurses to provide rapid screening and general practitioners (GPs) to treat individuals on-site. An electronic medical system tracked individuals through the cascade of care.

Results

The use of rapid tests allowed for screening of 60 769 people for HCV and HBV over 6 months and permitted outdoor testing during the COVID-19 pandemic along with COVID testing. 13%–14% of individuals were lost to follow-up after the rapid test, and another 62%–66% failed to come in for their consultation. One stop testing and treatment did not result in a statistically increase in retention and lack of patient awareness of viral hepatitis was identified as a key factor. Despite training, there were large differences between GPs and patients initiating treatment.

Conclusions

The current study demonstrated the feasibility of large-scale general population screening and task shifting in low- and middle-income countries. However, such programs need to be proceeded by awareness campaign to minimize loss to follow up. In addition, multiple trainings are needed for GPs to bolster their skills to talk to patients about treatment.  相似文献   
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Gene therapy is a highly attractive strategy for many types of inherited disorders of the immune system. Adenosine deaminase (ADA) deficient-severe combined immunodeficiency (SCID) has been the target of several clinical trials based on the use of hematopoietic stem/progenitor cells engineered with retroviral vectors. The introduction of a low intensity conditioning regimen has been a crucial factor in achieving stable engrafment of hematopoietic stem cells and therapeutic levels of ADA-expressing cells. Recent studies have demonstrated that gene therapy for ADA-SCID has favorable safety profile and is effective in restoring normal purine metabolism and immune functions. Stem cell gene therapy combined with appropriate conditioning regimens might be extended to other genetic disorders of the hematopoietic system.  相似文献   
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We present a case of a patient developing uterine prolapse during pregnancy. The cervix reached the introitus at 10 weeks gestation and subsequently protruted progressively as the pregnancy advanced. The patient was conservatively treated with bed rest and the main maternal and fetal risks are avoided. At 4 months postpartum follow-up there was no evidence of uterine prolapse.  相似文献   
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OBJECTIVE: To evaluate the efficacy of levetiracetam as prophylactic treatment for migraine with aura with high frequency of attacks. BACKGROUND: Migraine with aura with high frequency of attacks could represent a very demanding therapeutic problem. Efficacy of the antiepileptic drug, lamotrigine, has been reported in this form of migraine. Levetiracetam is a new antiepileptic drug with an excellent tolerability profile. Mechanisms of action of this drug remain largely unknown, but recently, it has been shown to exert inhibitory effects on neuronal-type calcium channels. METHODS: We performed a small open-label trial treating 16 patients affected by migraine with aura with high frequency of attacks. After a 1-month run-in period, patients were treated with levetiracetam at a dosage of 1000 mg/d for 6 months. RESULTS: The number of attacks per month was significantly reduced during the first month (compared with run-in; P < 0.001), and it was reduced further during the second (second month vs first month; P < 0.001) and the third months (third month vs second month; P < 0.001) of the treatment. This improvement persisted unchanged for the remaining 3 months of treatment. In 7 (44%) of the 16 patients, the attacks were completely abolished after 3 months of treatment. Severity of headache and duration of headache and aura were also significantly reduced at the third and sixth months of treatment (P < 0.001). Levetiracetam was well tolerated (6 patients complained of slight dizziness, nervousness, and somnolence). CONCLUSIONS: Levetiracetam seems to be a safe and effective treatment for migraine with aura. Controlled trials are needed to confirm the observed results.  相似文献   
50.
Cerebrospinal fluid (CSF) volume depletion syndrome is due to leakage of cerebrospinal fluid through lesions of the dural sac at the level of the cranial base or of the spine. When past medical history is negative for recent trauma or surgery, the term spontaneous intracranial hypotension (SIH) is used. SIH is characterized clinically by orthostatic headache, neck pain, nausea, emesis, horizontal diplopia, tinnitus, plugged ear, hearing difficulties, blurring of vision, facial numbness, and upper limb radicular symptoms. In SIH, brain and cervical MR scans show a diffuse pachymeningeal gadolinium enhancement that ends at the site of CSF leakage. The application of epidural blood patches has been proposed as an effective therapy for SIH. Here we describe a case of SIH with very unusual headache features; the patient reported a paradoxical pattern of postural headache provoked by clinostatic position. The CSF leakage was identified at the convexity of the skull and headache disappeared following treatment with fluid, analgesics and steroids.  相似文献   
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