Thalamus sends information about arousal but not valence to the amygdala

RATIONALE

The basolateral amygdala (BLA) and medial geniculate nucleus of the thalamus (MGN) have both been shown to be necessary for the formation of associative learning. While the role that the BLA plays in this process has long been emphasized, the MGN has been less well-studied and surrounded by debate regarding whether the relay of sensory information is active or passive.

OBJECTIVES

We seek to understand the role the MGN has within the thalamoamgydala circuit in the formation of associative learning.

METHODS

Here, we use optogenetics and in vivo electrophysiological recordings to dissect the MGN-BLA circuit and explore the specific subpopulations for evidence of learning and synthesis of information that could impact downstream BLA encoding. We employ various machine learning techniques to investigate function within neural subpopulations. We introduce a novel method to investigate tonic changes across trial-by-trial structure, which offers an alternative approach to traditional trial-averaging techniques.

RESULTS

We find that the MGN appears to encode arousal but not valence, unlike the BLA which encodes for both. We find that the MGN and the BLA appear to react differently to expected and unexpected outcomes; the BLA biased responses toward reward prediction error and the MGN focused on anticipated punishment. We uncover evidence of tonic changes by visualizing changes across trials during inter-trial intervals (baseline epochs) for a subset of cells.

CONCLUSION

We conclude that the MGN-BLA projector population acts as both filter and transferer of information by relaying information about the salience of cues to the amygdala, but these signals are not valence-specified.

Chronic Uncontrolled Hypothyroidism Associated With Dysphonia and Concurrent Pericardial Effusion

Hypothyroidism is a commonly encountered pathology within internal medicine. It commonly presents with symptoms of fatigue, weight gain, constipation, and dry skin. Long-standing uncontrolled hypothyroidism can manifest with atypical symptoms of dysphonia and even pericardial effusion. This constellation of findings is not often encountered concurrently. While likely a consequence of uncontrolled hypothyroidism, it is prudent to ensure appropriate protection of the patient’s airway and rule out other obstructive causes of dysphonia, such as malignancy. We present the case of a patient with uncontrolled hypothyroidism who presented with dysphonia. While treating hypothyroidism, the patient was found to have pericardial effusion. Other causes of obstruction such as vocal cord dysfunction and malignancy were ruled out via imaging studies and multidisciplinary discussion with other subspecialties.

Imaging Surveillance of Limited-stage Classic Hodgkin Lymphoma Patients After PET-CT-documented First Remission

INTRODUCTION

Early stage Hodgkin lymphoma (ESHL) is highly curable; however, 10% to 15% of patients experience relapse. We examined the utilization of follow-up imaging for patients with ESHL who achieved a metabolic complete response after upfront therapy.

MATERIALS AND METHODS

The records of adult patients treated at a single institution between 2003 and 2014 were reviewed. Positron emission tomography-computed tomography (PET-CT) and CT scan frequency was quantified during the 2 years following treatment and subsequent visits beyond 2 years.

RESULTS

The study cohort contained 179 patients. The median age was 31 years; bulky disease was present in 30%. ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) or AVD (doxorubicin, vinblastine, and dacarbazine) was given in 97%; 75% received radiation therapy. At a median follow-up of 6.9 years, the 5-year progression-free and overall survival rates were 93.7% and 98.1%, respectively. Relapse occurred in 5% (n = 9) of patients at a median of 9.1 months (range, 4.6-27.2 months) from therapy. Two patients presented with symptoms prompting imaging in follow-up. Within 2 years after therapy, 376 PET-CT scans and 3325 CT scans were performed, yielding an average of 2.1 PET-CTs and 18.6 CTs per patient. Of the initial 179 patients, 113 had follow-up conducted beyond 2 years post-therapy; an average of 2.7 PET-CTs and 33.2 CTs were performed. In the 2-year post-therapy period, 463 scans were performed per relapse detected.

CONCLUSION

In this cohort of patients with ESHL who responded completely to frontline therapy, the relapse rate was low. Routine imaging surveillance lacks clinical benefit in this patient population.

Corticoamygdala Transfer of Socially Derived Information Gates Observational Learning

Observational learning is a powerful survival tool allowing individuals to learn about threat-predictive stimuli without directly experiencing the pairing of the predictive cue and punishment. This ability has been linked to the anterior cingulate cortex (ACC) and the basolateral amygdala (BLA). To investigate how information is encoded and transmitted through this circuit, we performed electrophysiological recordings in mice observing a demonstrator mouse undergo associative fear conditioning and found that BLA-projecting ACC (ACC→BLA) neurons preferentially encode socially derived aversive cue information. Inhibition of ACC→BLA alters real-time amygdala representation of the aversive cue during observational conditioning. Selective inhibition of the ACC→BLA projection impaired acquisition, but not expression, of observational fear conditioning. We show that information derived from observation about the aversive value of the cue is transmitted from the ACC to the BLA and that this routing of information is critically instructive for observational fear conditioning. VIDEO ABSTRACT.

Nontoxic, double-deletion-mutant rabies viral vectors for retrograde targeting of projection neurons

Recombinant rabies viral vectors have proven useful for applications including retrograde targeting of projection neurons and monosynaptic tracing, but their cytotoxicity has limited their use to short-term experiments. Here we introduce a new class of double-deletion-mutant rabies viral vectors that left transduced cells alive and healthy indefinitely. Deletion of the viral polymerase gene abolished cytotoxicity and reduced transgene expression to trace levels but left vectors still able to retrogradely infect projection neurons and express recombinases, allowing downstream expression of other transgene products such as fluorophores and calcium indicators. The morphology of retrogradely targeted cells appeared unperturbed at 1 year postinjection. Whole-cell patch-clamp recordings showed no physiological abnormalities at 8 weeks. Longitudinal two-photon structural and functional imaging in vivo, tracking thousands of individual neurons for up to 4 months, showed that transduced neurons did not die but retained stable visual response properties even at the longest time points imaged.

SPIKES-A six-step protocol for delivering bad news: application to the patient with cancer

We describe a protocol for disclosing unfavorable information-"breaking bad news"-to cancer patients about their illness. Straightforward and practical, the protocol meets the requirements defined by published research on this topic. The protocol (SPIKES) consists of six steps. The goal is to enable the clinician to fulfill the four most important objectives of the interview disclosing bad news: gathering information from the patient, transmitting the medical information, providing support to the patient, and eliciting the patient's collaboration in developing a strategy or treatment plan for the future. Oncologists, oncology trainees, and medical students who have been taught the protocol have reported increased confidence in their ability to disclose unfavorable medical information to patients. Directions for continuing assessment of the protocol are suggested.

Antibiotic treatment of gastric lymphoma of mucosa-associated lymphoid tissue. An uncontrolled trial

BACKGROUND

Gastric lymphoma of mucosa-associated lymphoid tissue (MALT) is related to Helicobacter pylori infection and may depend on this infection for growth.

OBJECTIVE

To determine the response of gastric MALT lymphoma to antibiotic treatment.

DESIGN

Prospective, uncontrolled treatment trial.

SETTING

University hospital referral center and three collaborating university and community hospitals.

PATIENTS

34 patients with stage I or stage II N1 gastric MALT lymphoma.

INTERVENTION

Two of three oral antibiotic regimens--1) amoxicillin, 750 mg three times daily, and clarithromycin, 500 mg three times daily; 2)tetracycline, 500 mg four times daily, and clarithromycin, 500 mg three times daily; or 3) tetracycline, 500 mg four times daily, and metronidazole, 500 mg three times daily--were administered sequentially (usually in the order written) for 21 days at baseline and at 8 weeks, along with a proton-pump inhibitor (lansoprazole or omeprazole) and bismuth subsalicylate.

MEASUREMENTS

Complete remission was defined as the absence of histopathologic evidence of lymphoma on endoscopic biopsy. Partial remission was defined as a reduction in endoscopic tumor stage or 50% reduction in the size of large tumors.

RESULTS

34 patients were followed for a mean (+/-SD) of 41 +/- 16 months (range, 18 to 70 months) after antibiotic treatment. Of 28 H. pylori-positive patients, 14 (50% [95% CI, 31% to 69%]) achieved complete remission, 8 (29%) achieved partial remission (treatment eventually failed in 4 of the 8), and 10 (36% [CI, 19% to 56%]) did not respond to treatment. Treatment failed in all 6 (100% [CI, 54% to 100%]) H. pylori-negative patients. Patients with endoscopic appearance of gastritis (stage I T1 disease) were most likely to achieve complete remission within 18 months. Tumors in the distal stomach were associated with more favorable response than tumors in the proximal stomach.

CONCLUSIONS

A subset of H. pylori-positive gastric MALT lymphomas, including infiltrative tumors, may respond to antibiotics. The likelihood of early complete remission seems to be greatest for superficial and distal tumors.

Tumor downstaging and sphincter preservation with preoperative chemoradiation in locally advanced rectal cancer: the M. D. Anderson Cancer Center experience

PURPOSE

To evaluate the rates of tumor downstaging after preoperative chemoradiation for locally advanced rectal cancer.

MATERIALS AND METHODS

Preoperative chemoradiotherapy (CTX/XRT) that delivered 45 Gy in 25 fractions over 5 weeks with continuous infusion 5-fluorouracil (300 mg/m2/day) was given to 117 patients. The pretreatment stage distribution, as determined by endorectal ultrasound (u), included uT2N0 in 2%, uT3N0 in 47%, uT3N1 in 49%, and uT4N0 in 2% of cases; endorectal ultrasound was not performed in 13% of cases (15 patients). Approximately 6 weeks after completion of CTX/XRT, surgery was performed.

RESULTS

The pathological tumor stages were Tis-2N0 in 26%, T2N1 in 5%, T3N0 in 21%, T3N1 in 15%, T4N0 in 5%, and T4NI in 1%; a complete response (CR) to preoperative CTX/XRT was pathologically confirmed in 32 (27%) of patients. Tumor downstaging occurred in 72 (62%) cases. Only 3% of cases had pathologic evidence of progressive disease. Pretreatment tumor size (< 5 cm vs. > or = 5 cm) was the only factor predictive of tumor downstaging (p < 0.04). A decrease of > 1 T-stage level was accomplished in 45% of those downstaged. Overall, a sphincter-saving (SP) procedure was possible in 59% of patients and an abdominoperineal resection (APR) was required in 41 % of cases. Factors predictive of SP included downstaging (p < 0.03), age > 40 years (p < 0.007), pretreatment tumor distance, 3 to 6 cm from the anal verge (p < 0.00001), tumor size <6 cm (p < 0.02), mobility (p < 0.004), tumor stage <T4 (p < 0.01), and uN negative (p < 0.008). SP was performed in 23 patients (72%) with a CR and in 48 (67%) of downstaged cases. Among the 69 tumors located < 6 cm from the anal verge, 29 (42%) were resected with a SP. The level of response was important for tumors located < 6 cm from the anal verge because a SP was performed in 9 of the 17 (53%) CRs in this group while only 20 of 52 patients (38%) had a SP when residual disease was present after CTX/XRT. For tumors located > 6 cm from the anal verge, SP was performed in 14 of the 15 (93%) patients with a CR and 32 of 33 (97%) of patients with residual disease (p < 0.00004).

CONCLUSIONS

Significant tumor downstaging results from preoperative chemoradiation allowing sphincter sparing surgery in over 40% of patients whose tumors were located < 6 cm from the anal verge and who otherwise would have required colostomy.

Interobserver variability in endoscopic ultrasonography: a prospective evaluation

BACKGROUND

Endoscopic ultrasonography (EUS) is an imaging modality that is now widely used to stage gastrointestinal malignancies. Few studies have addressed the issue of interobserver variability in the interpretation of EUS, particularly as it pertains to the staging of rectal carcinoma.

METHODS

Twenty-six patients with a diagnosis of rectal carcinoma were evaluated prospectively by three endoscopists. One performed sigmoidoscopy, the second (primary endosonographer) performed an EUS staging examination with full knowledge of the patient history and sigmoidoscopic appearance of the lesion, and the third endoscopist (secondary endosonographer) performed EUS blinded to this information. The results of the respective examinations were then compared.

RESULTS

When the EUS findings of the endosonographers were compared, T stage agreed in 88% of patients, with the following kappa coefficients: T1 (kappa = 0.00); T2 (kappa = -0.04); T3 (kappa = -0.05); T4 (kappa = 0.00). Interrator N stage agreed in 73% of patients (kappa = 0.42).

CONCLUSION

Our study prospectively evaluated interobserver variation in staging rectal carcinoma by EUS. The protocol that was followed provides a useful template that eliminated potential observer bias. Fair agreement was demonstrated regarding lymph node assessment. Although the raters agreed in 88% of the patients, kappa statistic analysis did not reach significant agreement, due to this institution's preponderence of UT3 lesions. Thus, validation of our findings in a setting where a broader spectrum of disease is encountered is required.

Plasma IgA, IgG and IgM and their relationship to breast cancer in British, Japanese and Hawaiian-Japanese women

The plasma levels of immunoglobulins IgA, IgG and IgM have been measured in 35 British, 44 Hawaiian-Japanese and 37 Japanese healthy adult women. Previous investigations showed that the mean levels of all three immunoglobulins were higher in Japanese than in British normal women. The present study finds that Hawaiian-Japanese women have "Japanese" levels of IgA, "British" levels of IgM and are intermediate for IgG. Thus, plasma IgM concentrations correlate with breast cancer incidence rates in the three racial groups and the reduced amounts of plasma IgM found in Japanese patients with breast cancer support this association.

Simple computer quantitation of spleen-to-liver ratios in the diagnosis of hepatocellular disease

Increased splenic uptake of radiocolloids is a helpful sign in the scintigraphic diagnosis of various hepatocellular diseases, but little attempt has been made to quantify this physiologic phenomenon. We have devised a simple computer method that compares average splenic activity to average right-lobe liver activity. The method is reproducible (r = 0.97) and exhibits little interobserver variation (r = 0.99). One hundred clinically normal subjects were found to have a nearly symmetrical distribution of S/L ratios around a mean of 0.77, with a s.d. of 0.20. Fifteen subjects normal by biopsy were found to have a similar mean spleen-to-liver (S/L) ratio of 0.74. Based upon a normal range of 0.37 to 1.17 (0.77 +/- 2 s.d.), elevated S/L ratios were found in fatty metamorphosis (85%), cirrhosis (67%), and chronic hepatitis (43%). Abnormal S/L ratios in the range from 1.17 to approximately 1.4 were not visually obvious. Overall sensitivity of the S/L ratio in these three diseases is 69%. When combined with the other scintigraphic indications of hepatocellular disease (nonhomogenous colloid uptake, hepatomegaly, splenomegaly, and bone-marrow colloidal uptake), the liver scan was found to have a sensitivity of 93%.

ABO blood groups, rhesus factor and intestinal metaplasia of the stomach

The presence or absence of intestinal metaplasia of the stomach was determined in 272 patients by direct vision biopsy of standardized intragastric sites using fiberoptic gastroscopy. Analysis of ABO blood groupings and Rhesus factor failed to reveal an association with metaplasia.

Postoperative thromboembolism and the use of oral contraceptives

We have previously reported the results of a retrospective study of the relationship between oral contraceptives and deep vein thrombosis and pulmonary embolism occurring in the absence of an evident predisposing cause. The present paper describes a similar investigation of the relationship between oral contraceptives and thromboembolism following certain surgical procedures.Of 30 patients with thromboembolism, 12 (40%) had been using oral contraceptives during the month preceding surgery, while only 9 of 60 matched controls (15%) had been doing so. From these data it is estimated that the risk of postoperative thromboembolism is increased threefold to fourfold by the use of contraceptive steroids.It is recognized that few of the episodes of deep vein thrombosis and pulmonary embolism that occur postoperatively are detectable clinically, and that not all of these are recorded in discharge summaries or diagnostic indexes. Despite these considerations, we have been unable to detect any important bias in the data which could account for the observed association between oral contraceptives and the development of postoperative thromboembolism.