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101.
OBJECTIVE: A potential source of false-positive FDG PET interpretations in oncologic imaging is FDG uptake in brown fat. The purpose of this study was to determine the prevalence, location, and appearance of hypermetabolic brown fat in the mediastinum. MATERIALS AND METHODS: All PET/CT scans obtained at our cancer institution from August to October 2003 were retrospectively reviewed for increased FDG uptake in the mediastinum localized to fat on CT. The following features were recorded: location, appearance, maximal standard uptake value (SUV(max)) of hypermetabolic mediastinal brown fat, and presence of extramediastinal brown fat. RESULTS: PET/CT scans were obtained in 845 oncologic patients. Fifteen patients (1.8%) with focal hypermetabolic mediastinal brown fat were identified: nine women and two men (age range, 27-79; mean, 55.1 years) and four children (age range, 5-16 years; mean, 10 years). Hypermetabolic mediastinal brown fat (mean SUV(max), 5.7) was more common in children (4/8) than in adults (11/837) and more common in women (9/372) than in men (2/465). Foci of hypermetabolic brown fat were localized to the paratracheal, paraesophageal, prevascular, and pericardial regions; interatrial septum; and azygoesophageal recess. Five patients had focal hypermetabolic brown fat isolated to the mediastinum. Ten patients also had extramediastinal hypermetabolic brown fat in the neck, thorax, and abdomen. There was no difference in the body weight (p = 0.876) or body mass index (p = 0.538) of patients with hypermetabolic brown fat compared with age- and sex-matched control subjects. CONCLUSION: Hypermetabolic brown fat can be localized to the mediastinum and manifests as focal increased FDG uptake. Knowledge of this potential pitfall and precise localization with fusion PET/CT are important in preventing misinterpretation as malignancy.  相似文献   
102.
Objective.?The objective of this study was to examine the rate of respiratory morbidity in neonates delivered by elective cesarean delivery (ECD) at term, with a definite confirmation of gestational age (GA) by 1st-trimester ultrasound.

Methods.?Consecutive women carrying a singleton pregnancy and undergoing ECD at term (>38 1/7 weeks), confirmed by 1st-trimester ultrasound, were included in the study group. Multiple gestations, cesarean section (CS) in labor, CS performed after rupture of membranes and induced deliveries were excluded. The control group included women with a singleton pregnancy at term (>38 1/7 weeks) who delivered spontaneously. This group of women was randomly selected during the study period.

Results.?The study group included 277 women delivered by ECD. The control group consisted of 311 women. Five newborns in the study group and none in the control group were admitted to the neonatal intensive care unit (NICU) due to respiratory disorders (p < 0.02). Excluding diabetic women did not change the results. On multivariate analysis, no other factors were found to independently influence the risk of respiratory complications.

Conclusion.?In our study, the rate of respiratory morbidity was found to be significantly higher in neonates delivered by ECD compared to those delivered vaginally. The fact that GA was confirmed by 1st-trimester ultrasound makes iatrogenic prematurity an unlikely sole cause for this excess morbidity.  相似文献   
103.
Zilberman D  Inbar Y  Heyman Z  Shinhar D  Bilik R  Avigad I  Jonas P  Ramon J  Mor Y 《The Journal of urology》2006,175(6):2287-9; discussion 2289
PURPOSE: The literature concerning undescended testis mainly concentrates on the increased risks of infertility and development of germ cell tumors. Yet the UDT also appears to be at higher risk for torsion compared to the normally descended testis, and this issue is relatively poorly addressed. We reviewed all cases of torsion of UDTs operated on at our hospital during the last 20 years in an attempt to characterize better this condition and its salvageability. MATERIALS AND METHODS: In this retrospective clinical study we reviewed and analyzed all cases of testicular torsion involving UDT operated on at our hospital between 1984 and 2004. RESULTS: A total of 11 children were operated on at our hospital for torsion of undescended testis between 1984 and 2004. Patient age ranged from 1 month to 18 years (median 7.5 months). In all cases unilateral torsion of undescended testis was diagnosed, with 73% of cases involving the left side. Clinical symptoms included inguinal swelling and erythema associated with a tender, firm mass palpated in the groin area and an empty ipsilateral hemiscrotum. Doppler ultrasound examination was routinely performed in the last 7 patients to confirm the diagnosis. During inguinoscrotal exploration severe ischemia or overt necrosis of the testis was found in 5 of 11 cases. Three of these 5 cases were managed by orchiectomy, while in the other 2 cases the testis subsequently vanished. In the 6 patients who exhibited some improvement following detorsion and warming of the tissue the testes were preserved and orchiopexy was performed. Followup was available in only 5 patients, with vanishing of the torsed testis observed in 4 and a normal testicle detected 21 years postoperatively in 1 patient who was diagnosed early. CONCLUSIONS: This series clearly demonstrates poor rates of surgical salvage, which we mainly attribute to delays in parental response and in primary physician referral to the hospital. Parents, who have a pivotal role in early diagnosis, were usually unaware of this urological emergency, and some were surprisingly unaware of the presence of cryptorchidism. By increasing the awareness regarding this entity among members of the medical community and parents, we hope that torsion of the cryptorchid testis (literally, "hidden testis") will no longer necessarily be synonymous with "crypt-torsion" ("hidden torsion").  相似文献   
104.

Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Methods

Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.

Results

Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).

Conclusions

Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF.  相似文献   
105.
The menstrual cycle has been implicated as a sex‐specific biological process influencing psychological symptoms across a variety of disorders. Limited research exists regarding the role of the menstrual cycle in psychological symptoms among women with posttraumatic stress disorder (PTSD). The current study examined the severity of a broad range of psychological symptoms in both the early follicular (Days 2–6) and midluteal (6–10 days postlutenizing hormone surge) phases of the menstrual cycle in a sample of trauma‐exposed women with and without PTSD (N = 49). In the sample overall, total psychological symptoms (d = 0.63), as well as depression (d = 0.81) and phobic anxiety (d = 0.81) symptoms, specifically, were increased in the early follicular compared to midluteal phase. The impact of menstrual cycle phase on phobic anxiety was modified by a significant PTSD × Menstrual Phase interaction (d = 0.63). Women with PTSD reported more severe phobic anxiety during the early follicular versus midluteal phase, whereas phobic anxiety did not differ across the menstrual cycle in women without PTSD. Thus, the menstrual cycle appears to impact fear‐related symptoms in women with PTSD. The clinical implications of the findings and future research directions are discussed.  相似文献   
106.
We report resolution of an epileptic encephalopathy by administration of transdermal nicotine patches in an adolescent with severe nonlesional refractory frontal lobe epilepsy. The 18.5‐year‐old female patient had refractory epilepsy from the age of 11. Recurrent electroencephalography (EEG) recordings showed mostly generalized activity, albeit with right frontal predominance. Almost all antiepileptic medications failed to provide benefit. She developed an encephalopathic state with cognitive decline. The nonlesional frontal lobe epilepsy and a family history of a cousin with nocturnal epilepsy with frontal origin suggested genetic etiology. Transdermal nicotine patches brought complete resolution of the seizures, normalization of the EEG, and a significant improvement in her thinking process and speech organization. Sequencing of the CHRNB2 and CHRNA4 genes did not detect a mutation. Transdermal nicotine patches should be considered in severe pharmacoresistant frontal lobe epilepsy.  相似文献   
107.
Parents of children with disabilities vary in their reaction to their children's diagnosis. The current study focused on fathers in addition to mothers and examined their resolution and coping styles when having children diagnosed with developmental delay (DD). Sixty-five fathers and 71 mothers were interviewed using the reaction to the diagnosis interview (RDI; Pianta & Marvin, 1992a). Results indicated that the majority of parents were unresolved with their child's diagnosis, with no differences found between fathers’ and mothers’ rates of resolution. Furthermore, both parents of children that were diagnosed at a later age and parents that were less educated tended to be unresolved, as did fathers of a lower socioeconomic status. Older age of both children and mothers was related to maternal lack of resolution. Finally, an in-depth examination revealed significant differences in the manner in which fathers and mothers cope with their children's diagnosis: whereas mothers were more prone to using an emotional coping style, fathers tended to use a cognitive coping style. The clinical implications of paternal versus maternal coping styles are discussed.  相似文献   
108.
Objective: Most research concerning the implications of self-disclosure on trauma’s aftermath has focused on the salubrious effects disclosure may foster for the primary victim. However, the manner in which recipients of disclosure are symptomatically affected by it remains unexamined. Of particular interest are spouses who are often the primary support providers and are therefore susceptible to secondary traumatization. Assessing posttraumatic stress symptoms (PTSS) and self-disclosure among traumatized veterans and their wives, the current longitudinal study begins to fill this gap in the literature. Method: A total of 220 couples consisting of Israeli veterans, of whom 128 were former prisoners of war (ex-POWs) and 92 were combatants, and their wives were examined. PTSS and self-disclosure of both partners were assessed 30 and 35 years after the war using the Posttraumatic Stress Disorder Inventory (PTSD-I; Solomon et al., 1993) and the Self-Disclosure Index (SDI; Miller, Berg, & Archer, 1983), respectively. Analyses included Pearson intercorrelations analyses and four stepwise hierarchical multiple regression analyses. Results: Findings indicated that increments in veterans’ disclosure are not only consistently associated with the reduction of their wives’ PTSS but may also explain and predict some of the change in the wives’ PTSS over time. However, such a longitudinal effect was not evident concerning the veterans’ PTSS. Conclusion: Traumatized ex-POWs’ and combatants’ self-disclosure within the marital relationship may contribute to the amelioration of their wives’ secondary traumatization, and thus may be a goal worth pursuing in therapy. However, more research is needed to further understand this relation.  相似文献   
109.
The present study examined functional impairment among treatment seekers with social anxiety disorder (SAD). We investigated the effects of diagnostic subtypes of SAD and comorbidity with mood and anxiety disorders on impairment. In addition, we used cluster analysis procedures to empirically identify subgroups of individuals with distinct patterns of impairment. Participants were 216 treatment-seeking individuals with SAD. Clinical interviews were undertaken to determine diagnoses of anxiety disorders and major depressive disorder, and a battery of self-report measures was administered to index symptoms of social anxiety, depression and extent of impairment. Results indicated that individuals with the generalized subtype of SAD had greater impairment in all three life domains compared to individuals with the nongeneralized subtype. Comorbidity with mood disorders was associated with greater impairment than SAD alone, but comorbidity with anxiety disorders was not. Four distinct impairment profiles emerged from the cluster analysis: primary work/studies impairment, primary social life impairment, both work/studies and social impairment, and impairment in all domains. Findings from this study suggest that SAD is associated with substantial impairment across multiple domains, and that individuals with SAD present diverse impairment profiles. These profiles may inform subtyping of the disorder as well as therapeutic interventions.  相似文献   
110.

Background

Measurements and models of current flow in the brain during transcranial Direct Current Stimulation (tDCS) indicate stimulation of regions in-between electrodes. Moreover, the folded cortex results in local fluctuations in current flow intensity and direction, and animal studies suggest current flow direction relative to cortical columns determines response to tDCS.

Methods

Here we test this idea by using Transcranial Magnetic Stimulation Motor Evoked Potentials (TMS-MEP) to measure changes in corticospinal excitability following tDCS applied with electrodes aligned orthogonal (across) or parallel to M1 in the central sulcus.

Results

Current flow models predicted that the orthogonal electrode montage produces consistently oriented current across the hand region of M1 that flows along cortical columns, while the parallel electrode montage produces non-uniform current directions across the M1 cortical surface. We find that orthogonal, but not parallel, orientated tDCS modulates TMS-MEPs. We also show modulation is sensitive to the orientation of the TMS coil (PA or AP), which is thought to select different afferent pathways to M1.

Conclusions

Our results are consistent with tDCS producing directionally specific neuromodulation in brain regions in-between electrodes, but shows nuanced changes in excitability that are presumably current direction relative to column and axon pathway specific. We suggest that the direction of current flow through cortical target regions should be considered for targeting and dose-control of tDCS.  相似文献   
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