Motivational, proteostatic and transcriptional deficits precede synapse loss, gliosis and neurodegeneration in the B6.HttQ111/+ model of Huntington's disease

We investigated the appearance and progression of disease-relevant signs in the B6.Htt^Q111/+ mouse, a genetically precise model of the mutation that causes Huntington’s disease (HD). We find that B6.Htt^Q111/+ mice are healthy, show no overt signs of central or peripheral inflammation, and no gross motor impairment as late as 12 months of age. Behaviorally, we find that 4–9 month old B6.Htt^Q111/+ mice have normal activity levels and show no clear signs of anxiety or depression, but do show clear signs of reduced motivation. The neuronal density, neuronal size, synaptic density and number of glia is normal in B6.Htt^Q111/+ striatum, the most vulnerable brain region in HD, up to 12 months of age. Despite this preservation of the synaptic and cellular composition of the striatum, we observe clear progressive, striatal-specific transcriptional dysregulation and accumulation of neuronal intranuclear inclusions (NIIs). Simulation studies suggest these molecular endpoints are sufficiently robust for future preclinical studies, and that B6.Htt^Q111/+ mice are a useful tool for modeling disease-modifying or neuroprotective strategies for disease processes before the onset of overt phenotypes.

Annuloplasty and aortoplasty as modifications of the Ross procedure for the correction of geometric mismatch

BACKGROUND AND AIM OF THE STUDY

Pulmonary autograft replacement of the aortic valve (the Ross procedure) is reliable and durable; however, geometric mismatch of the autograft and systemic outflow tract may lead to poor results. Manipulation of the aortic annulus and sinotubular diameters to match the autograft can prevent geometric mismatch, and improve results.

METHODS

Annuloplasty and/or aortoplasty were combined with the Ross procedure in 26 of 44 patients (median age 42.5 years; range: 3 days to 62 years) undergoing surgery between April 1994 and July 1998. Plication of the aortic annulus at either two or three of the commissures was done in five cases, aortic annulus fixation with an external pericardial pledget incorporated in the proximal suture line in 12 cases, and tailoring aortoplasty in nine patients.

RESULTS

There was one operative death. Two patients required reoperation; one for progressive autograft dysfunction and one for homograft dysfunction. Annular fixation was performed on the patient requiring reoperation for autograft dysfunction. Doppler echocardiography during the follow up (median 9 months; range: 1-50 months) revealed 10 patients with trace 1+ and one patient with 2+ aortic insufficiency. Trace 1+ and 2+ aortic stenosis were present in one patient each. None of the patients undergoing commissural plication had significant regurgitation or stenosis. Both patients with stenosis underwent annular fixation. Aortoplasty was associated with 1+ insufficiency in two patients.

CONCLUSION

Prevention of geometric mismatch between the autograft and systemic outflow tract at the annulus and sinotubular junction by plication techniques allows better performance of the autograft, and extends the Ross procedure to patients who otherwise may be unable to undergo such surgery. Fixation may provide similar benefit, but appears to be more susceptible to insufficiency and stenosis.

Purposeful delay in the repair of a traumatic rupture of the aorta with coexistent liver injury

Purposeful delay in the repair of traumatic aortic injury by appropriate medical management is indicated when the risk of immediate thoracotomy is high. A grade V liver injury implies parenchymal disruption of greater than 75% of a hepatic lobe. We report the successful management of a patient with a class IB proximal descending aortic transection and concomitant grade V liver injury that precluded aortic repair until its resolution.

Efficacy and cost-effectiveness of preoperative IABP in patients with ejection fraction of 0.25 or less

BACKGROUND

The purposes of this study are to determine whether patients with severe left ventricular dysfunction benefit from prophylactic insertion of an intraaortic balloon pump and to evaluate its cost-effectiveness.

METHODS

Between January 1991 and December 1995, 163 consecutive patients with a left ventricular ejection fraction of 0.25 or less underwent isolated coronary artery bypass grafting. An intraaortic balloon pump was inserted before operation in 37 patients (group A). The remaining 126 patients underwent operation without preoperative insertion of the device (group B). Preoperatively, 91.9% (34/37) of group A patients and 54.8% (69/126) of group B patients were in New York Heart Association functional class III or IV (p < 0.001).

RESULTS

The 30-day mortality rate was 2.7% (1/37) and 11.9% (15/126) for groups A and B, respectively (p < 0.005). All deaths occurred in patients in functional class III or IV. In group B, 28 patients (22.2%) required an intraaortic balloon pump after cardiotomy for low cardiac output, 42.9% (12/28) of whom died. Median postoperative hospital stay was 9.9 days and 12.0 days, and mean hospital charges were $50,627 and $54,818 for survivors in groups A and B; respectively (p = not significant).

CONCLUSIONS

Our experience suggests that patients with severe left ventricular dysfunction undergoing coronary artery bypass grafting may benefit from preoperative intraaortic balloon pump insertion, especially patients in functional class III or IV. This approach improved survival significantly, reduced hospital stay, and was more cost-effective.

Which is the graft of choice for the right coronary and posterior descending arteries? Comparison of the right internal mammary artery and the right gastroepiploic artery

BACKGROUND

The graft of choice for the left anterior descending coronary artery is the left internal mammary artery because of superior long-term patency. However, controversy exists regarding the graft of choice for the right coronary artery and for the posterior descending branch.

METHODS AND RESULTS

Two types of pedicled arterial grafts were used for the right coronary and the posterior descending arteries in patients undergoing coronary bypass surgery between January 1991 and September 1994. Group A comprised 114 patients with a right internal mammary artery (RIMA) graft, and group B consisted of 127 patients with an in situ right gastroepiploic artery (R-GEA) graft. Mean age was 56.9 years in group A and 63.3 years in group B; 7.9% (9 of 114) and 33.9% (43 of 127) were diabetics in groups A and B, respectively. Overall mortality was 2.6% (3 deaths) for group A and 3.9% (5 deaths) for group B (P = NS). However, the prevalence of perioperative myocardial infarction in the right coronary artery distribution was significantly higher for group A (5.3%, or 6 of 114) than for group B (0.8%, or 1 of 127; P < .05), and the reoperation rate for graft failure (from 0 to 12 months after surgery) was significantly higher for the RIMA (4.4%, or 5 of 114) than for the R-GEA (0%; P < .05). Also, the prevalence of deep sternal wound infection in diabetics was significantly higher in group A (22.2%, or 2 of 9) than in group B (4.6%, or 2 of 43; P < .05).

CONCLUSIONS

Our preliminary results suggest that the failure rate of the RIMA graft is significantly higher, especially if used as a pedicled graft to the posterior descending artery. The risk of sternal wound complications is greater in diabetics if both internal mammary arteries are used for grafting. Therefore, the R-GEA graft is preferred in diabetics and whenever the posterior descending artery is the target vessel.

Tumor cell lines established in vitro: an independent prognostic factor for survival in non-small-cell lung cancer

OBJECTIVE

To determine the relation between in-vitro establishment of tumor cell lines and survival in patients with non-small-cell lung cancer.

DESIGN

Cohort study.

SETTING

Single-institution tertiary care center.

PATIENTS

One hundred twenty-three consecutive patients with non-small-cell lung cancer from whom a viable tumor specimen could be obtained.

INTERVENTION

Tumor tissue was removed at the time of entry into a therapeutic protocol. The tumor tissue was processed in the laboratory for attempted cell-line establishment. Patients classified as potentially curable (stages I, II, and IIIA) were treated with surgical resection, radiation therapy, or a combination. Patients suitable for palliative therapy only (stages IIIB and IV) were treated with radiation therapy with or without chemotherapy. Chemotherapy was based on in-vitro drug sensitivity when available. Cell-line establishment was correlated to clinical outcome.

MEASUREMENTS AND MAIN RESULTS

Univariate analysis of survival was done using the log-rank test; multivariate analysis was done by Cox modeling step-up and step-down techniques. Cell lines were established from the tumor specimens of 25 patients (20%). Those patients experienced a median survival of 7 months compared with 18 months in patients from whom cell lines could not be established (P less than 0.001). In the 61 patients with potentially curable disease, 8 patients (13%) with cell lines established had a median survival of 8 months compared with 32 months for those without cell lines established (P = 0.001). In the 62 palliative group patients, the median survival of the 17 patients (27%) from whom tumor cell lines were established was 5 months compared with 7 months for those without cell lines (P = 0.15). Multivariate analysis in both groups showed cell-line establishment to be a significant indicator of prognosis (P less than 0.0001 for curable group; P less than 0.01 for palliative group).

CONCLUSION

In-vitro tumor growth is related to decreased patient survival, which in turn reflects the biologic aggressiveness of cancers giving rise to these tumor cell lines.

Myasthenia gravis-associated antibodies in asymptomatic thymoma

Serum antibodies associated with myasthenia gravis were evaluated before and after therapy in an asymptomatic patient having a malignant thymoma. The case illustrates that myasthenia-associated antibodies may also be useful as a tumor marker of thymoma in the work-up of mediastinal masses, in evaluating therapy of thymoma, and possibly in detecting recurrence of thymoma and potential for developing myasthenia gravis.

Noncardiac clinical applications of seven-pinhole tomography

Clinical examples of various noncardiac seven-pinhole tomographic scans are shown. In many cases, this method of emission tomography can provide a very useful extension of standard planar nuclear medicine images. Major advantages of seven-pinhole tomography include reasonable cost and improved lesion detectability due to increased image contrast. Disadvantages include rather difficult patient positioning, nonuniform plane spacing with depth, and sometimes rather long data processing times because the presently available computer algorithms are maximized for cardiac scans.

Incorporation of the terminal phosphate of ATP into membranal protein of rabbit cardiac sarcoplasmic reticulum. Correlation with active calcium transport and study of the effects of cyclic AMP

The transfer of the terminal phosphate of ATP to a material from the sarcoplasmic reticulum of cardiac muscle which can be precipitated by trichloroacetic acid was studied, and the relationship of this biochemical event to active Ca 2+ transport was examined. A component of the phosphoryl transfer reaction was stimulated specifically by Ca 2+ . Both the phosphorylation of the reticulum and the active sequestering of Ca 2+ were proportional to the Ca 2+ concentration between 10 -7 and 10 -5 M. The time course of both phenomena was similar. These and other observations relating Ca 2+ -dependent phosphorylation of the membrane of the sarcoplasmic reticulum with the activesequestering of Ca 2+ suggest that the phosphoryl transfer reaction may represent the formation of a carrier system which facilitates the inward flux of Ca 2+ against a concentration gradient. Cyclic AMP, theophylline, or the combination of these two agents did not influence the rate or extent of the phosphorylation of the sarcoplasmic reticulum. These results have led us to question the hypothesis that the cardiac sarcoplasmic reticulum is the site of action of cyclic AMP in its role as a mediator of cardiac inotropic effects.