Bronchoscopic long-term palliation of a recurrent atypical carcinoid tumor

Bronchial carcinoid tumors account for 1-2% of all primary lung tumors and are separated into 2 subgroups: typical and atypical carcinoids. Atypical carcinoids as intermediate-grade malignancies can metastasize more frequently, thus exhibiting poorer prognosis than the low-grade typical carcinoid tumors. Surgical resection remains the mainstay of treatment for pulmonary carcinoids. Bronchoscopic treatment using ablation techniques is an effective alternative to surgery in selected patients with typical carcinoid tumors. However, evidence is lacking regarding the effect of bronchoscopic resection of atypical carcinoid tumor and its recurrences. We report the case of a 73-year-old male with frequent endobronchial recurrences of a previously surgically resected atypical carcinoid tumor successfully treated using Nd:YAG laser photoresection. Furthermore, the therapeutic and local staging aspects of the disease are discussed emphasizing the efficacy of bronchoscopic resection strategies and the value of novel bronchoscopic imaging techniques in detailed inspection of the structures of the bronchial wall.     

A negative correlation between the induction of long-term potentiation and activation of immediate early genes.

In the present study we examined the relationship between the induction of long-term potentiation (LTP) in the dentate gyrus of anesthetized rats and activation of immediate early genes (IEGs; c-fos and zif/268) using several different high-frequency stimulation paradigms. Stimulation parameters that effectively induced LTP were not associated with IEG activation. Conversely, stimulation parameters that failed to induce LTP consistently resulted in IEG activation. These results suggest that there is a negative correlation between IEG activation and LTP, and that activation of IEGs is neither necessary nor sufficient for the induction of LTP.     

Differential effects of ketamine and MK-801 on the induction of long-term potentiation.

Ketamine and MK-801 are phencyclidine (PCP)-like noncompetitive antagonists of the N-methyl-D-aspartate (NMDA) receptor that produce a use-dependent blockade of the NMDA receptor-coupled channel. Recent studies have suggested that the binding properties of these drugs to the NMDA receptor in-vitro are different. In the present study, the effects of ketamine and MK-801 on the induction of long-term potentiation (LTP) were compared at perforant path--granule cell synapses in anaesthetized rats. LTP was observed in animals treated with either saline or MK-801, but not in those treated with ketamine. These results reveal that ketamine and MK-801 differentially modulate the induction of LTP, and we propose that this differential modulation may be related to the different binding properties of the drugs.     

Basolateral amygdaloid multi-unit neuronal correlates of discriminative avoidance learning in rabbits

Basolateral (BL) amygdaloid multi-unit activity was recorded as male albino rabbits learned to avoid a foot-shock unconditioned stimulus (US) by stepping in an activity wheel to an acoustic (pure tone) warning stimulus (CS+). A second tone (CS−) of different auditory frequency than the CS+ was presented in an irregular order on half of the conditioning trials but was never followed by the US. BL amygdaloid neurons developed, in the first session of conditioning, enhanced CS-elicited discharges relative to discharges recorded during pretraining with tones and noncontingent US presentations (excitatory plasticity), and greater discharges to the CS+ than to the CS− (discriminative plasticity). The discriminative plasticity attained maximal magnitude as the rabbits reached the asymptote of behavioral discrimination, and persisted during post-asymptotic training. Peak excitatory plasticity occurred in the session of the first significant behavioral discrimination and decline during the asymptotic and post-asymptotic stages of training. Similar patterns of excitatory and discriminative plasticity in structures directly interconnected with the BL nucleus (anterior cingulate cortex; medial dorsal thalamic nucleus) and effects of lesions suggest that the neurons in these areas participate in a circuit involved in mediation of avoidance learning.     

Feasibility of an ovarian cancer quality-of-life psychoeducational intervention

Background. Diagnosis of ovarian cancer often portends a poor prognosis with significant quality-of-life (QOL) concerns. Method. We report on a pilot study that tested the feasibility of a structured, ovarian cancer psychoeducational intervention (OCPI). Patients (N=33) were randomly assigned to either the control or OCPI study arms in which those in the intervention arm received 4 sequential, structured, in-person educational sessions. Data were collected at the time of accrual and at 1 and 3 months postaccrual. Results. This study demonstrated the feasibility of a structured psychoeducational program in an outpatient clinical setting. Conclusion. Study findings underscore the importance of developing interventions that address the 4 QOL domains impacted by ovarian cancer and support initiating a comprehensive psychoeducational intervention earlier in the course of illness.     

Prognostic factors in the treatment of carpal scaphoid nonunions.

The aim of this multicenter study of 138 patients with scaphoid nonunions was to assess the prognostic factors of bone healing or failure after curative surgical treatment options: isolated bone grafting (30%), internal fixation (23%), or combined bone grafting and internal fixation (47%). Bone healing occurred in 75% of cases. Persistent nonunion was evident in 20% of cases; it was possible in 6%. The clinical and radiologic results were worse in the group of failures. Stepwise multiple logistic regression analysis was conducted to identify the factors of prognosis toward bone healing or failure. In univariate analysis, professional heavy work, age of the nonunion of over 5 years, associated radial styloidectomy, and duration of postoperative immobilization were associated with a significantly decreased likelihood of healing of the scaphoid nonunion. In multivariate analysis, the only remaining predictor was the delay between the initial trauma and the treatment of the nonunion. Among the cases of internal fixation (with or without bone grafting), the only predictor in multivariate analysis was the importance of bone resorption. The dorsal approach resulted in a more pronounced loss of wrist flexion and extension amplitudes. If the time elapsed between the initial fracture and the treatment of the nonunion exceeds 5 years, the chances of healing of the nonunion are decreased.     

Pain Sensitivity in Sleepy Pain-Free Normals

Study Objective:

Past studies have shown that acute experimental reduction of time in bed in otherwise healthy, non-sleepy people leads to hyperalgesia. We hypothesized that otherwise healthy, sleepy people may also exhibit hyperalgesia relative to their non-sleepy counterparts.

Design:

Between-groups sleep laboratory study.

Setting:

Hospital-based sleep disorders center.

Participants:

Twenty-seven, healthy, normal participants (age 18–35 years) were recruited and categorized into sleepy and non-sleepy groups based on their average sleep latencies on a screening multiple sleep latency test (MSLT).

Interventions:

Both groups were then allowed 8 hours time in bed, following which they underwent pain sensitivity testing (10:30 and 14:30) and sleepiness assessments by the MSLT (10:00, 12:00, 14:00, and 16:00). Pain sensitivity assessments were made by measuring finger withdrawal latencies to a radiant heat source delivering 5 different heat intensities.

Measurements and Results:

This study showed that after only one night of 8 hours time in bed, the sleepy participants continued to be sleepy and exhibited a more rapid finger withdrawal response (i.e., increased pain sensitivity) to radiant heat than non-sleepy participants.

Conclusion:

This suggests that sleepy individuals experience hyperalgesia in response to a painful stimulus when compared with non-sleepy individuals.

Citation:

Chhangani BS; Roehrs TA; Harris EJ; Hyde M; Drake C; Hudgel DW; Roth T. Pain sensitivity in sleepy pain-free normals. SLEEP 2009;32(8):1011-1017.     

Modulating parameters of excitability during and after transcranial direct current stimulation of the human motor cortex

Weak transcranial direct current stimulation (tDCS) of the human motor cortex results in excitability shifts which occur during and after stimulation. These excitability shifts are polarity-specific with anodal tDCS enhancing excitability, and cathodal reducing it. To explore the origin of this excitability modulation in more detail, we measured the input–output curve and motor thresholds as global parameters of cortico-spinal excitability, and determined intracortical inhibition and facilitation, as well as facilitatory indirect wave (I-wave) interactions. Measurements were performed during short-term tDCS, which elicits no after-effects, and during other tDCS protocols which do elicit short- and long-lasting after-effects. Resting and active motor thresholds remained stable during and after tDCS. The slope of the input–output curve was increased by anodal tDCS and decreased by cathodal tDCS. Anodal tDCS of the primary motor cortex reduced intracortical inhibition and enhanced facilitation after tDCS but not during tDCS. Cathodal tDCS reduced facilitation during, and additionally increased inhibition after its administration. During tDCS, I-wave facilitation was not influenced but, for the after-effects, anodal tDCS increased I-wave facilitation, while cathodal tDCS had only minor effects. These results suggest that the effect of tDCS on cortico-spinal excitability during a short period of stimulation (which does not induce after-effects) primarily depends on subthreshold resting membrane potential changes, which are able to modulate the input-output curve, but not motor thresholds. In contrast, the after-effects of tDCS are due to shifts in intracortical inhibition and facilitation, and at least partly also to facilitatory I-wave interaction, which is controlled by synaptic activity.     

Influence of the menstrual cycle on proenkephalin peptide F responses to maximal cycle exercise

Proenkephalin peptide F [107–140] is an enkephalin-containing peptide found predominantly within the adrenal medulla and is co-packaged with epinephrine within adrenal medullary chromaffin granules. Peptide F has been shown to have the classic opioid analgesia effects along with immune cell interactions. This is only the second peptide F study in women, and in it we compare the responses of peptide F to a maximal cycle exercise test and recovery values over the follicular and luteal phases of the menstrual cycle. Eight untrained (directly documented in this study) women who were eumenorrheic performed a progressive maximal exercise test to volitional exhaustion on a cycle ergometer, once during the follicular phase, and once during the luteal phases of the menstrual cycle. Blood was obtained pre-exercise, immediately post-exercise and at 0, 15, and 30 min into recovery. Typical exercise changes in response to the cycle tests were observed with blood lactate increases that remained elevated 30 min into recovery. No significant exercise-induced elevations were observed for peptide F concentrations with exercise nor were any differences observed between the two menstrual phases. Thus, the effects of the menstrual cycle on peptide F concentrations appear to be minimal under the conditions of this investigation. With high concentrations of peptide F observed at rest (approx. 0.2–0.3 pmol ml⁻¹) pre-exercise arousal mechanisms may have obviated any exercise-induced response. In addition, inhibition via elevated epinephrine may have inhibited any post-exercise increases and finally adrenal medullary capacity for circulatory concentrations of peptide F may have been reached in such untrained women. Pre-exercise arousal mechanisms potentially related to analgesia may also be involved to prepare untrained women for the stress of maximal exercise.