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41.

Background

The status of the sentinel lymph node is an important predictor for survival in melanoma patients, but it is still unclear if early removal of micrometastases by sentinel lymph node dissection (SLND) alters survival. A large series of melanoma patients from a single center with long-term follow-up was analyzed with regard to a possible effect of SLND on the prognosis.

Materials and Methods

A total of 673 consecutive melanoma patients were assessed treated in our center either without SLND (377 patients, pre-SLN group, between January 1995 and March 2000) or with SLND (296 patients, SLN group, between April 2000 and March 2003). The median follow-up was 64.0 months in the pre-SLN and 72.5 months in the SLN group.

Results

The pre-SLN group and SLN group did not differ significantly with regard to characteristics of the primary melanoma thickness and ulceration, sex, and age. Kaplan–Meier analyses showed a significantly better recurrence-free survival (P < .001), distant metastases free survival (P = .006), and overall survival (P = .049) for patients of the SLN group; the 5-year melanoma-specific survival rates were 80.3% in pre-SLN patients and 84.8% in SLN patients. Initial metastases in the in-transit region and distant locations were of similar frequency in the pre-SLN and SLN groups (P = .191 and P = .959, respectively), but initial regional lymph node metastases were significantly more frequent in the pre-SLN group (P < .001).

Conclusions

Our data point toward a subgroup of melanoma patients who might have a prognostic benefit from SLN.  相似文献   
42.

Background

Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment for depression, but only some individuals respond. Predicting response could reduce patient and clinical burden. Neural activity related to working memory (WM) has been related to mood improvements, so may represent a biomarker for response prediction.

Primary hypotheses

We expected higher theta and alpha activity in responders compared to non-responders to rTMS.

Methods

Fifty patients with treatment resistant depression and twenty controls performed a WM task while electroencephalography (EEG) was recorded. Patients underwent 5–8 weeks of rTMS treatment, repeating the EEG at week 1 (W1). Of the 39 participants with valid WM-related EEG data from baseline and W1, 10 were responders. Comparisons between responders and non-responders were made at baseline and W1 for measures of theta (4–8 Hz), upper alpha (10–12.5 Hz), and gamma (30–45 Hz) power, connectivity, and theta-gamma coupling. The control group's measures were compared to the depression group's baseline measures separately.

Results

Responders showed higher levels of WM-related fronto-midline theta power and theta connectivity compared to non-responders at baseline and W1. Responder's fronto-midline theta power and connectivity was similar to controls. Responders also showed an increase in gamma connectivity from baseline to W1, with a concurrent improvement in mood and WM reaction times. An unbiased combination of all measures provided mean sensitivity of 0.90 at predicting responders and specificity of 0.92 in a predictive machine learning algorithm.

Conclusion

Baseline and W1 fronto-midline theta power and theta connectivity show good potential for predicting response to rTMS treatment for depression.  相似文献   
43.
A method of combined cataract extraction with posterior chamber intraocular lens and trabeculectomy using separate incisions was tested in 44 operations on 38 patients. The mean preoperative intraocular pressure (IOP) of 28.1 ± 11.7 (range 12 to 56) mmHg on maximum medication was lowered to 13.9 ± 3.4 (9 to 23) mmHg at one year, with half the eyes still requiring topical medication. The IOP was 40 mmHg or more preoperatively in eight eyes and 20 mmHg or more in only two patients at one year. There were no rises in IOP above 20 mmHg in the early postoperative period (days 1 and 2). Visual acuity was 6/9 or better in 27 and 6/12 in three eyes. There was an expulsive haemorrhage in one case, rupture of the posterior capsule in two eyes and a choroidal detachment in one eye, but no flat anterior chambers. The two-incision method allowed placement of an intraocular lens with good postoperative pressure control.  相似文献   
44.
We know a great deal about the cellular response to starvation via AMPK, but less is known about the reaction to nutrient excess. Insulin resistance may be an appropriate response to nutrient excess, but the cellular sensors that link these parameters remain poorly defined. In the present study we provide evidence that mitochondrial superoxide production is a common feature of many different models of insulin resistance in adipocytes, myotubes, and mice. In particular, insulin resistance was rapidly reversible upon exposure to agents that act as mitochondrial uncouplers, ETC inhibitors, or mitochondrial superoxide dismutase (MnSOD) mimetics. Similar effects were observed with overexpression of mitochondrial MnSOD. Furthermore, acute induction of mitochondrial superoxide production using the complex III antagonist antimycin A caused rapid attenuation of insulin action independently of changes in the canonical PI3K/Akt pathway. These results were validated in vivo in that MnSOD transgenic mice were partially protected against HFD induced insulin resistance and MnSOD+/− mice were glucose intolerant on a standard chow diet. These data place mitochondrial superoxide at the nexus between intracellular metabolism and the control of insulin action potentially defining this as a metabolic sensor of energy excess.  相似文献   
45.

Objectives

To examine the effects of intermittent TBS (iTBS) and continuous TBS (cTBS) on cortical reactivity in the dorsolateral prefrontal cortex.

Methods

10 healthy participants were stimulated with either iTBS, cTBS or sham at F3 electrode. Single- and paired-pulse TMS and concurrent electroencephalography (EEG) were used to assess change in cortical reactivity and long-interval intracortical inhibition (LICI) via TMS-evoked potentials (TEPs) and TMS-evoked oscillations.

Results

Significant increases in N120 amplitudes (p < 0.01) were observed following iTBS over prefrontal cortex. Changes in TMS-evoked theta oscillations and LICI of theta oscillations were also observed following iTBS (increase) and cTBS (decrease). Change in LICI of theta oscillations correlated with change in N120 amplitude following TBS (r = ?0.670, p = 0.001).

Conclusions

This study provides preliminary evidence that TBS produces direct changes in cortical reactivity in the prefrontal cortex. Combining TBS with TMS-EEG may be a useful approach to optimise stimulation paradigms prior to the conduct of clinical trials.

Significance

TBS is able to modulate cortical reactivity and cortical inhibition in the prefrontal cortex.  相似文献   
46.
Despite numerous reports that different markers are expressed by horizontal cells in the avian retina, it remains unknown whether different types of horizontal cells can be defined by differences in their immunocytochemical profiles. The purpose of this study was to rectify this deficiency. We identified horizontal cells by indirect immunofluorescence with antibodies to calretinin, trkA, GABA, Prox1, AP2alpha, Pax6, islet1, and Lim1 + 2. We found two major groups of horizontal cells, those that express trkA and those that express calretinin. The trkA-immunoreactive (-IR) horizontal cells had small, round somata and robust, bulbous dendritic endings, whereas calretinin-IR horizontal cells had large, polygonal cell bodies and fine, diffuse dendritic endings, both contacting the calbindin-IR pedicles of double cones. Weak gamma-aminobutyric acid (GABA) immunoreactivity was observed only in a few of the trkA-IR horizontal cells, whereas the overlap of calretinin and GABA immunoreactivities was 100%. The majority of trkA-IR horizontal cells expressed islet1, and the majority of calretinin-IR horizontal cells expressed Lim1 + 2, AP2alpha, and Pax6. Islet1 immunoreactivity was observed in a small fraction of calretinin-IR/non-trkA-IR cells. In agreement with previous reports, we detected Prox1 immunoreactivity in all types of horizontal cells. These immunolabeling profiles suggest that there are four immunochemically distinct subtypes of horizontal cells in the postnatal chick retina, which may match the four types that have been observed in Golgi-impregnated pigeon and turtle retinas.  相似文献   
47.
Thrombocytopenia is a common serious adverse effect of drug treatment. A variety of in vitro diagnostic techniques to confirm the diagnosis are available, but the majority lack sufficient sensitivity to detect all cases of drug-induced thrombocytopenia. We studied 19 patients with suspected drug-induced thrombocytopenia and demonstrated that platelet- associated IgG (PAIgG) was elevated in all at the time of thrombocytopenia, and PAIgG returned to normal levels as the thrombocytopenia resolved. In the majority of patients, the platelet count rapidly returned to normal after the drug was discontinued; however, in six patients, the thrombocytopenia persisted well beyond the period of time that the offending drug would be expected to be cleared from the blood. In 13 patients, serum obtained after recovery was used to identify the drug responsible for the thrombocytopenia in an in vitro assay. In all cases, the addition of the drug historically associated with the thrombocytopenic episode was associated with an increased binding of IgG to control platelets. For uncertain reasons, the concentration of drug required to increase the in vitro binding of IgG to test platelets was often more than the concentration usually achieved in vivo. Wider application of these techniques may provide better understanding of the clinical characteristics and mechanisms responsible for drug-induce thrombocytopenia.  相似文献   
48.
49.
50.

Purpose

A number of studies have found an ethnic density effect in psychotic disorders, where the incidence for ethnic minorities increases as the neighbourhood proportional ethnic composition decreases [Morgan and Hutchinson, Psychol Med 40:705–709, (2010); Singh, Psychol Med 39:1402–1403, (2009); Schofield et al., Psychol Med 41:1263–1269, (2010)]. However, there is a mixed picture with some studies reporting no effect [Schofield et al., Psychol Med 41:1263–1269, (2010)]. This review aimed to establish the existence of the effect by answering the review question: is there an ethnic density dose effect in the prevalence of psychotic disorders?

Methods

A systematic review and meta-analysis was conducted by two independent reviewers using PsychINFO, Web of Science and PubMed databases. Studies were measured against eligibility criteria and then pooled with any discrepancies discussed between reviewers. Studies were then assessed for quality using a standardised quality assessment.

Results

In total, eight studies were included. A meta-analysis was conducted which found that the incidence of psychotic disorders was higher in low ethnic density areas than high ethnic density areas. A narrative synthesis reflected the complexity when results were broken down by individual ethnic groups where some ethnic groups had inverse or no associations with ethnic density. The synthesis also analysed methodological differences between studies.

Conclusions

The review reports evidence of an overall ethnic density dose effect for ethnic minorities, but with more mixed results for individual ethnic groups. The possible mechanisms behind this effect are explored, including exposure to racism, social capital and social cohesion hypotheses. The wide-ranging implications of the review are discussed along with recommendations for future research to continue to inform public health policy.  相似文献   
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