Three-dimensional printed pure-titanium implantation for chest wall reconstruction involving the sternum and ribs: a novel approach

Chest wall reconstruction is challenging due to the complex shape and large defect size. The three-dimensional printing technology enables the fabrication of customized implants, and 3D-printed pure-titanium could provide superior mechanical properties to conventional materials. The aim of this study was to evaluate long-term outcomes of patients undergoing chest wall reconstruction with a 3D-printed pure-titanium implant. Between August 2018 and May 2021, 5 patients underwent surgery due to sternal metastasis (n = 3), postoperative sternal wound infection (n = 1) and deformity (n = 1). The customized implant was designed and constructed based on the size and shape of the chest wall defect measured on computed tomography. All patients demonstrated uneventful recovery without complications during the hospital course. During the median follow-up of 20 months, 1 patient underwent revision surgery due to implant breakage, and 1 removed the implant due to trauma-related chest wall infection. One patient died from cancer progression, while 3 patients are alive without any implant-related complications. Chest wall reconstruction using a 3D-printed pure-titanium implant could be a novel alternative for patients with various conditions affecting the sternum and ribs.

Importance of Lymph Node Evaluation in ≤2-cm Pure-Solid Non-Small Cell Lung Cancer

BACKGROUND

The prevalence of lymph node (LN) metastasis in small-sized lung cancer varies depending on the tumor size and proportion of ground-glass opacity. We investigated occult LN metastasis and prognosis in patients with small-sized non-small cell lung cancer (NSCLC), mainly focusing on the pure-solid tumor.

METHODS

We retrospectively reviewed patients with ≤2-cm clinical N0 NSCLC who underwent lung resection with curative intent from 2003 to 2017. Among them we analyzed patients who also underwent adequate complete systematic LN dissection. Pathologic results and disease-free survival of the radiologically mixed ground-glass nodule (mGGN) and pure-solid nodule (PSN) groups were analyzed.

RESULTS

Of 1329 patients analyzed, 591 had mGGNs and PSNs. As tumor size increased, patients in the mGGN group showed no difference in LN metastasis: ≤1 cm, 2.27%; 1.0 to 1.5 cm, 2.19%; and 1.5 to 2.0 cm, 2.18% (P = .999). However the PSN group showed a significant difference in LN metastasis as the tumor size increased: ≤1 cm, 2.67%; 1.0 to 1.5 cm, 12.46%; and 1.5 to 2.0 cm, 21.31% (P < .001). In the multivariate analysis tumor size was a significant predictor of nodal metastasis in the PSN group but not in the mGGN group. In terms of 5-year disease-free survival, the mGGN group showed a better prognosis than the PSN group (94.4% vs 71.2%, P < .001).

CONCLUSIONS

We need to conduct a thorough LN dissection during surgery for small-sized NSCLC, especially for pure-solid tumors ≥ 1 cm.

Distinct Recurrence Pattern and Survival Outcomes of Invasive Mucinous Adenocarcinoma of the Lung: The Potential Role of Local Therapy in Intrapulmonary Spread

BACKGROUND

Invasive mucinous adenocarcinoma (IMA) is distinct from non-mucinous adenocarcinoma, but studies on recurrent IMA are scarce. Thus, this study aimed to evaluate the recurrence patterns of IMA and the role of pulmonary local therapy (LT) in resectable pulmonary recurrence of IMA.

METHODS

The study reviewed 403 patients with surgically resected IMA between 1998 and 2018. The recurrence patterns were categorized as solitary pulmonary recurrence (SPR), multiple pulmonary recurrence (MPR), and extra-pulmonary recurrence (EPR). The clinicopathologic characteristics, overall survival (OS), and post-recurrence survival (PRS) were analyzed according to the recurrence pattern and LT administration.

RESULTS

Recurrences were found in 91 (22.6%) patients, including 18 patients with SPR, 37 patients with MPR, and 36 patients with EPR. Compared with the MPR and EPR groups, the SPR group had a longer disease-free interval (32.5 vs. 9.6 vs. 10.1 months, respectively; p < 0.01) and a better OS (5-year OS: 88.5%, 41.5%, and 22.9%, respectively; p < 0.01). In case of resectable pulmonary recurrence, pulmonary LT was administered to 15 patients with SPR and 3 patients with MPR. These patients showed a better 5-year PRS than the other patients with pulmonary recurrence (86.3% vs. 30.4%; p < 0.01). Notably, long-term survival was observed for one patient with MPR undergoing LT and two patients with SPR undergoing a second LT for a second pulmonary recurrence.

CONCLUSIONS

In this series, the patients with recurrent IMA showed different prognoses according to the recurrence pattern. The patients with pulmonary recurrence of IMA undergoing LT showed a favorable prognosis, suggesting the potential role of LT for resectable pulmonary recurrence of IMA.

Reappraising the clinical usability of consolidation-to-tumor ratio on CT in clinical stage IA lung cancer

Objectives

Ground-glass opacity (GGO) on computed tomography is associated with prognosis in early-stage non-small cell lung cancer (NSCLC) patients. However, the stratification of the prognostic value of GGO is controversial. We aimed to evaluate clinicopathologic characteristics of early-stage NSCLC based on the consolidation-to-tumor ratio (CTR), conduct multi-pronged analysis, and stratify prognosis accordingly.

Methods

We retrospectively investigated 944 patients with clinical stage IA NSCLC, who underwent curative-intent lung resection between August 2018 and January 2020. The CTR was measured and used to categorize patients into six groups (1, 0%; 2, 0–25%; 3, 25–50%; 4, 50–75%; 5, 75–100%; and 6, 100%).

Results

Pathologic nodal upstaging was found in 1.8% (group 4), 9.0% (group 5), and 17.4% (group 6), respectively. The proportion of patients with a high grade of tumor-infiltrating lymphocytes tended to decrease as the CTR increased. In a subtype analysis of patients with adenocarcinoma, all of the patients with predominant micro-papillary patterns were in the CTR > 50% groups, and most of the patients with predominant solid patterns were in group 6 (47/50, 94%). The multivariate analysis demonstrated that CTR 75–100% (hazard ratio [HR], 3.85; 95% confidence interval [CI], 1.58–9.36) and CTR 100% (HR, 5.58; 95% CI, 2.45–12.72) were independent prognostic factors for DFS, regardless of tumor size.

Conclusion

We demonstrated that the CTR could provide various noninvasive clinicopathological information. A CTR of more than 75% is the factor associated with a poor prognosis and should be considered when making therapeutic plans for patients with early-stage NSCLC.

Conditional Survival of Surgically Treated Patients with Lung Cancer: A Comprehensive Analyses of Overall, Recurrence-free, and Relative Survival

Purpose

Survival probability changes over time in cancer survivors. This study examined conditional survival in patients undergoing curative resection for non-small cell lung cancer (NSCLC).

Materials and Methods

Five-year conditional recurrence-free survival (CRFS), conditional overall survival (COS), and conditional relative survival (CRS) up to 10 years after surgery were calculated in patients who underwent NSCLC resection from 1994 to 2016. These rates were stratified according to age, sex, year of diagnosis, pathological stage, tumor histology, smoking status, comorbidity, and lung function.

Results

Five-year CRFS increased from 65.6% at baseline to 90.9% at 10 years after surgery. Early differences in 5-year CRFS according to stratified patient characteristics disappeared, except for age: older patients exhibited persistently lower 5-year CRFS. Five-year COS increased from 72.7% to 78.3% at 8 years and then decreased to 75.4% at 10 years. Five-year CRS increased from 79.0% at baseline to 86.8% at 10 years. Older age and higher pathologic stage were associated with lower 5-year COS and CRS up to 10 years after surgery. Female patients, those with adenocarcinoma histology, non-smokers, patient without comorbidities and had good lung function showed higher COS and CRS.

Conclusion

CRFS improved over time, but significant risk remained after 5 years. CRS slightly improved over time but did not reach 90%, suggesting significant excess mortality compared to the general population. Age and stage remained significant predictors of conditional survival several years after surgery. Our conditional survival estimates should help clinicians and patients make informed treatment and personal life decisions based on survivorship status.

Conditional relative survival and competing mortality in patients who underwent surgery for lung cancer: A nationwide cohort study

We aimed to investigate the conditional relative survival (CRS) and competing mortality in patients who underwent surgery for newly diagnosed lung cancer. Using a nationwide population-based database, we calculated 5-year CRS on 1 to 5 years survival after surgery. These rates were reported according to age, sex, socioeconomic status, comorbidities and treatment received. We also estimated cause-specific mortality with the consideration of competing risk. We identified 34 349 patients newly diagnosed with primary lung cancer from 2007 to 2013. The 5-year CRS after surgery was 71.7% at baseline improving steadily to 85.4% by 5 years, suggesting evidence of persistent excess mortality risk. Throughout the period, lung cancer was the most common cause of death, contributing to 83.6% mortality 1 year after surgery and 66.3% 5 years after surgery. Other causes of death included cardiovascular disease and respiratory disease, which increased continuously with time after surgery. CRS rates for patients with lung cancer improved over time but did not reach the level of the general population even 5 years after surgery. Although the main cause of death continues to be lung cancer, death from noncancer causes increased with time after surgery. Evidence-based decisions could be made on the dynamic risk profiles of the patients.

Impact of previous percutaneous coronary intervention on cardiovascular outcomes and mortality after lung cancer surgery: A nationwide study in Korea

Background

The number of patients with operable lung cancer with a history of percutaneous coronary intervention (PCI) has increased. However, cardiovascular outcomes and mortality, according to the time from PCI to surgery, and the follow‐up time after surgery are largely unknown. Here, we aimed to compare the cardiovascular outcomes and mortality of these patients with a history of PCI to those of patients without a history of PCI.

Methods

Using the Korean National Health Insurance Service Database, we selected 30 750 patients who underwent surgery for lung cancer between 2006 and 2014. Study outcome variables were all‐cause mortality, revascularization, intensive care unit (ICU) readmission, and stroke incidence. Patients were followed‐up until 2016.

Results

Of the 30 750 patients, 513 (1.7%) underwent PCI before surgery. The PCI group did not show an increased risk of death, ICU readmission, or stroke within one year of surgery, despite an increased risk of revascularization. However, one year after surgery, they showed a higher risk of death and revascularization than the non‐PCI group. The risk of revascularization was highest when the interval between PCI and surgery was <1 year and remained high when the interval was >3 years.

Conclusions

Patients who underwent PCI before surgery for lung cancer were at a higher risk of death than those in the non‐PCI group at one year after surgery. In addition, they showed higher short‐ and long‐term risks of revascularization than patients in the non‐PCI group. Careful long‐term management of cardiovascular risk is necessary for this population.

Cardiovascular risk and undertreatment of dyslipidemia in lung cancer survivors: A nationwide population-based study

BACKGROUND

In lung cancer survivors, cardiovascular diseases (CVDs) are the leading cause of noncancer deaths. Nonetheless, there is lack of information on management of dyslipidemia, a major risk factor for future CVD events, in lung cancer survivors. This study aimed to assess dyslipidemia management and prevalence of statin eligibility in lung cancer survivors.

METHODS

From the Korean National Health Insurance Service database, we selected 7349 lung cancer survivors who received surgery for lung cancer from 2007 to 2014. We used descriptive statistics for analyses of dyslipidemia management status on the basis of the National Cholesterol Education Program Adult Treatment Panel III guidelines. We also identified those who met the criteria for treatment on the basis of CVD risk according to the 2018 American College of Cardiology and American Heart Association (ACC/AHA) guidelines.

RESULTS

The overall awareness and treatment rates for lung cancer survivors with dyslipidemia were 31.8% and 29.7%, respectively. The overall control rate for those receiving treatment was 88.7%, but was lowest in the highest risk group (78.1%). Furthermore, undertreatment of dyslipidemia was more prominent in young, male lung cancer survivors and those diagnosed with lung cancer within 3 years. Among those not receiving treatment for dyslipidemia, 61.7% were indicated for statin according to the ACC/AHA guidelines.

CONCLUSION

Over half of lung cancer survivors were not receiving treatment, although they were eligible for statin under current guidelines. To reduce noncancer mortality, statin use and adequate management of CVD risk factors should be encouraged in lung cancer survivors.

Increased risk of coronary heart disease and stroke in lung cancer survivors: A Korean nationwide study of 20,458 patients

OBJECTIVES

With advances in lung cancer treatments, the number of lung cancer survivors has increased. As cardiovascular diseases (CVD) are some of the major causes of non-cancer deaths, CVD management is an integral part of cancer survivorship care. However, there is sparsity of data on cardiovascular risk in lung cancer survivors who underwent lung cancer surgery. We aimed to compare the incidence of CVD between lung cancer survivors and the general non-cancer population.

MATERIALS AND METHODS

Using the Korean National Health Insurance Service Database, we selected 20,458 patients who underwent surgery for lung cancer between 2007 and 2013. Study outcome variables were coronary heart disease (CHD), myocardial infarction (MI), ischemic stroke (IS), and death. Patients were followed until 2016.

RESULTS

A total of 20,458 lung cancer patients undergoing lung cancer surgery were compared to 27,321 non-cancer control subjects. Lung cancer survivors showed a greater risk for all cardiovascular (CV) events (adjusted hazard ratio [aHR] = 1.27, 95% confidence interval [CI]: 1.19-1.36), CHD (aHR = 1.26, 95% CI: 1.16-1.36), and IS (aHR = 1.22, 95% CI: 1.07-1.39). Chemotherapy and radiotherapy were associated with an increased risk of CV events, CHD, and MI. Lung cancer survivors who were CV event-free for one year, and up to three years, were still at a higher risk for all CV events compared to the non-cancer control population.

CONCLUSIONS

Lung cancer survivors showed an increased risk of CHD and IS compared with the general non-cancer population. Therefore, paying careful attention to cardiovascular risk in lung cancer survivors is suggested, especially for those who receive chemotherapy and/or radiotherapy, in order to ensure both early and long-term survivorship.

Late Reoperation Following Ligation of the Left Main Coronary Artery in a Patient with Infective Endocarditis

We report the case of a female patient who underwent late reoperation following endocarditis surgery. The patient first underwent surgery at 22 years of age for endocarditis with aortic and tricuspid insufficiency. She underwent aortic root replacement with a homograft and tricuspid valve replacement with a tissue valve. Coronary artery bypass using the internal thoracic artery and ligation of the left main coronary artery were performed. Ten years later, failure of the homograft and the tricuspid valve developed. In the second operation, the patient underwent a successful Bentall operation and tricuspid valve replacement with a mechanical valve under deep hypothermia and retrograde cold cardioplegia without drainage.

Non-intubated video-assisted thoracoscopic lung biopsy for interstitial lung disease: a single-center experience

Background

The mortality and morbidity associated with video-assisted thoracoscopic (VATS) lung biopsy for interstitial lung disease (ILD) are not negligible. We evaluated whether non-intubated VATS lung biopsy, which avoids intubation and general anesthesia, can be safely performed in ILD subjects.

Methods

This retrospective study compared the incidence of complications and surgical mortality between 25 consecutive intubated subjects and 10 non-intubated subjects (a total of 35 consecutive subjects) at a single institution.

Results

No major surgical complications or deaths were reported in either group, and non-intubated VATS biopsies were safely performed in subjects with relatively low carbon monoxide diffusing capacity (P=0.08) or poor American Society of Anesthesiologists physical status scores (ASA) (P=0.02).

Conclusions

These preliminary results suggest that non-intubated VATS lung biopsy is a safe and feasible option in patients with ILD.

The Ross Procedure in Pediatric Patients: A 20-Year Experience of Ross Procedure in a Single Institution

Background

The Ross/Ross-Konno procedure is considered a good option for irreparable aortic valve disease in pediatric patients because of its hemodynamic performance and potential for growth of the pulmonary autograft. This study is a review of the long-term results of our 20-year experience with the Ross and Ross-Konno operations in a single institution.

Methods

Between June 1995 and January 2016, 16 consecutive patients (mean age, 6.0±5.9 years; range, 16 days to 17.4 years) underwent either a Ross operation (n=9) or a Ross-Konno operation (n=7). The study included 12 males and 4 females, with a median follow-up period of 47 months (range, 6 to 256 months).

Results

There were no cases of in-hospital or late mortality. Six reoperations were performed in 5 patients. Four patients underwent right ventricular-pulmonary artery (RV-PA) conduit replacement. Two patients underwent concomitant replacement of the pulmonary autograft and RV-PA conduit 10 years and 8 years after the Ross operation, respectively. The rate of freedom from adverse outcomes of the pulmonary autograft was 88% and 70% at 5 and 10 years, respectively. The rate of freedom from valve-related reoperations was 79% and 63% at 5 and 10 years, respectively.

Conclusion

Pulmonary autografts demonstrated good durability with low mortality. The Ross/Ross-Konno procedure is a good option that can be performed safely in pediatric patients with aortic valve disease, even in a small-volume center.

Predictors of survival in patients who underwent video-assisted thoracic surgery talc pleurodesis for malignant pleural effusion

Background

Patients with malignant pleural effusion have a limited life expectancy. An increase in pleural and oncological treatment options and more accurate prognostic evaluation may help individualize treatment strategies. The aim of this study was to identify the prognostic indicators of overall survival (OS) after video‐assisted thoracic surgery (VATS) talc pleurodesis for malignant pleural effusion.

Methods

We examined the medical records of all consecutive patients with malignant pleural effusion who underwent VATS talc pleurodesis from 2006 to 2008 at the Samsung Medical Center. Univariate and multivariate analyses were used to identify predictors of OS after VATS talc pleurodesis.

Results

During the study period, 91 patients underwent VATS talc pleurodesis to treat malignant pleural effusion. Early (within 30 days) and late (within 90 days) postoperative mortality rates were 9.9% (9 patients), and 25.3% (23), respectively. Median survival time after VATS talc pleurodesis was 10.5 months. The postoperative respiratory complication rate was 11% (10 patients), and included pneumonia (9) and acute respiratory distress syndrome (4). Multivariate analysis revealed that preoperative chemotherapy (P = 0.012), preoperative radiotherapy (P = 0.003), and Eastern Cooperative Oncology Group (ECOG) performance score 3 or 4 (P = 0.013) were independent risk factors of OS after VATS talc pleurodesis.

Conclusions

We identified previous chemotherapy or radiotherapy and poor performance status (ECOG 3 or 4) as significant predictors of OS after VATS talc pleurodesis. These prognostic factors can help surgeons select candidates for VATS pleurodesis for malignant pleural effusion.

Isolated Tricuspid Regurgitation: Initial Manifestation of Cardiac Amyloidosis

Amyloid deposits in the heart are not exceptional in systemic amyloidosis. The clinical manifestations of cardiac amyloidosis may include restrictive cardiomyopathy, characterized by progressive diastolic and eventually systolic bi-ventricular dysfunction; arrhythmia; and conduction defects. To the best of our knowledge, no previous cases of isolated tricuspid regurgitation as the initial manifestation of cardiac amyloidosis have been reported. We describe a rare case of cardiac amyloidosis that initially presented with severe tricuspid regurgitation in a 42-year-old woman who was successfully treated with tricuspid valve replacement. Unusual surgical findings prompted additional evaluation that established a diagnosis of plasma cell myeloma.

Pulmonary Root Translocation with the Lecompte Maneuver: For Transposition of the Great Arteries with Ventricular Septal Defect and Pulmonary Stenosis

A five-month-old boy who had undergone previously transcatheter balloon atrioseptostomy at 3 days of age for complete transposition of the great arteries with ventricular septal defect and pulmonary stenosis underwent pulmonary root translocation with the Lecompte maneuver. This operation has the advantages of maintaining pulmonary valve function, preserving the capacity for growth, and avoiding problems inherent to the right ventricular to pulmonary artery conduit. This patient progressed well for 9 months postoperatively and we report this case of pulmonary root translocation with the Lecompte maneuver.

Carotid atherosclerosis in patients with untreated chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with systemic inflammation.

OBJECTIVE

To evaluate carotid artery intima-media thickness (IMT), high sensitivity C-reactive protein (hsCRP) and their correlation in newly diagnosed untreated patients with COPD.

DESIGN

Post-bronchodilator spirometry, carotid artery IMT and blood tests were measured in patients with COPD (COPD group). Age, sex, body mass index, smoking status and smoking amount were compared with matched healthy subjects (non-COPD group). Participants taking medications and/or with a history of hypertension, diabetes mellitus, dyslipidaemia, COPD or cardiovascular disease were excluded.

RESULTS

A total of 126 patients (COPD group 42, non-COPD group 84) were enrolled. The IMT and hsCRP of the COPD group were significantly higher than in the non-COPD group (P < 0.05). The decrease in the forced expiratory volume in 1 second/forced vital capacity (FEV(1)/FVC) ratio and FEV(1) was significantly correlated with an increase in the hsCRP and IMT (P < 0.05); there was no correlation between the IMT and hsCRP (P = 0.152).

CONCLUSION

In newly diagnosed untreated patients with COPD, the carotid artery IMT and hsCRP were significantly higher than in healthy subjects. These findings suggest that systemic inflammation may play a potential role in preclinical atherosclerosis in COPD.

Comparison of two immunization schedules for a Pseudomonas aeruginosa outer membrane proteins vaccine in burn patients

The aim of the present study was to compare two immunization schedules for a Pseudomonas aeruginosa outer membrane proteins (OMPs) vaccine in burn patients. In a double-blind, randomized and placebo-controlled clinical trial, 95 adult patients with burn injuries in 10% or greater of total body surface area were randomly allocated to either placebo or immunization groups. Three doses of the vaccine (0.5 or 1.0 mg) were administered intramuscularly at either 3- or 7-day intervals. The vaccine was well tolerated, and no severe adverse reactions were observed in any of the vaccinees. After three immunizations, 88 patients were available for evaluation of serum antibody titers. Elevation of OMPs-specific antibody titers in the immunization groups was significantly higher as compared with the placebo group, and the highest antibody response was obtained by immunization with 1.0-mg doses at 3-day intervals. Conventional blood culture, tissue culture of wound biopsy specimens and a nested polymerase chain reaction (PCR) assay of blood specimens were performed to determine the protective efficacy. The results of the nested PCR indicated that the overall detection rate of P. aeruginosa in blood was significantly lower among immunized patients than placebo patients (6.1 vs. 40.0%, P<0.001). Based on these results, we concluded that the P. aeruginosa OMPs vaccine is safe and highly immunogenic in burn patients, especially with 1.0-mg doses at 3-day intervals, and may be effective in conferring protection against P. aeruginosa bacteremia in burn patients.

Measurement of air exchange rate of stationary vehicles and estimation of in-vehicle exposure

The air exchange rates or air changes per hour (ACH) were measured under 4 conditions in 3 stationary automobiles. The ACH ranged between 1.0 and 3.0 h-1 with windows closed and no mechanical ventilation, between 1.8 and 3.7 h-1 for windows closed with fan set on recirculation, between 13.3 and 26.1 h-1 for window open with no mechanical ventilation, and between 36.2 and 47.5 h-1 for window closed with the fan set on fresh air. ACHs for windows closed with no ventilation were higher for the older automobile than for the newer automobiles. With the windows closed and fan turned off, ACH was not influenced by wind speed (p > 0.05). When the window was open, ACH appeared to be greatly affected by wind speed (R2 = 0.86). These measurements are relevant to understanding exposures inside automobiles to sources such as dry-cleaned clothes, cigarettes and airbags. Therefore, to understand the in-vehicle exposure to these internal sources, perchloroethylene (PCE) emitted from dry-cleaned clothes and environmental tobacco smoke (ETS) inside a vehicle were modeled for simulated driving cycles. Airbag deployment was also modeled for estimating exposure level to alkaline particulate and carbon monoxide (CO). Average exposure to PCE inside a vehicle for 30 minutes period was high (approximately 780 micrograms/m3); however, this is only 6% of the two-week exposure that is influenced by the storage of dry cleaned clothing at home. On the other hand, the exposure levels of respirable suspended particulate (RSP) and formaldehyde due to ETS could reach 2.1 mg/m3 and 0.11 ppm, respectively, when a person smokes inside a driving car even with the window open. In modeling the in-vehicle concentrations following airbag deployment, the average CO level over 20 minutes would not appear to present problem (less than 28 ppm). The peak concentration of respirable particulate would have exceeded 140 mg/m3. Since most of the particle mass is composed of alkaline material, these high levels might be expected to cause harmful effects on susceptible people, such as asthmatics. In all modeled cases, ACH would significantly affect build-up and dilution of pollutants originating from internal sources. Frequent stopping in congested urban traffic can greatly increase short-term exposures.

Genetic variation of herpesvirus saimiri subgroup A transforming protein and its association with cellular src

Herpesvirus saimiri strain 11 of subgroup A contains a gene called the saimiri transformation-associated protein, STP, which is not required for viral replication but is required for in vitro immortalization and for the lymphoma-inducing capacity of the virus. To assess the effects of sequence variation on STP function, STP genes from six subgroup A isolates were cloned and sequenced. Sequence comparisons revealed extensive amino acid substitutions within the central region, but the acidic amino terminus and the hydrophobic carboxyl terminus were well conserved. Amino acid identities varied from 73 to 99% among all two-way comparisons. The highly conserved YAEV/I motif at amino acid residues 115 to 118 was preceded by negatively charged glutamic acid residues and thus matched very well the consensus sequence for binding to SH2 domains of src family kinases. The STPs of these subgroup A strains were shown to associate with cellular src and to be an in vitro substrate for src kinase. Mutational analysis of STP-A11 showed that binding to src kinase required the tyrosine residue at 115, showing that YAEV/I is a likely binding motif for src. Also, tyrosine phosphorylation of STP-A11 by src led to subsequent binding to lck and fyn in vitro. Thus, the association of STP with src is likely to be important for T-cell transformation by subgroup A strains of herpesvirus saimiri.

Tap: a novel cellular protein that interacts with tip of herpesvirus saimiri and induces lymphocyte aggregation

Tip of herpesvirus saimiri associates with Lck and down-regulates Lck-mediated activation. We identified a novel cellular Tip-associated protein (Tap) by a yeast two-hybrid screen. Tap associated with Tip following transient expression in COS-1 cells and stable expression in human Jurkat-T cells. Expression of Tip and Tap in Jurkat-T cells induced dramatic cell aggregation. Aggregation was likely caused by the up-regulated surface expression of adhesion molecules including integrin alpha, L-selectin, ICAM-3, and H-CAM. Furthermore, NF-kappaB transcriptional factor of aggregated cells had approximately 40-fold higher activity than that of parental cells. Thus, Tap is likely to be an important cellular mediator of Tip function in T cell transformation by herpesvirus saimiri.

Kaposi's sarcoma-associated herpesvirus encodes a functional cyclin

Kaposi's sarcoma-associated herpesvirus (KSHV) (also called human herpesvirus 8) is consistently found in Kaposi's sarcoma lesions and in body-cavity-based lymphomas. A 17-kb KSHV lambda clone was obtained directly from a Kaposi's sarcoma lesion. DNA sequence analysis of this clone identified an open reading frame which has 32% amino acid identity and 53% similarity to the virus-encoded cyclin (v-cyclin) of herpesvirus saimiri (HVS) and 31% identity and 53% similarity to human cellular cyclin D2. This KSHV open reading frame was shown to encode a 29- to 30-kDa protein with the properties of a v-cyclin. KSHV v-cyclin protein was found to associate predominantly with cdk6, a cellular cyclin-dependent kinase known to interact with cellular type D cyclins and HVS v-cyclin. The KSHV v-cyclin was also found to associate weakly with cdk4. KSHV v-cyclin-cdk6 complexes strongly phosphorylated glutathione S-transferase-Rb fusion protein and histone H1 as substrates in vitro. Thus, KSHV v-cyclin resembles the v-cyclin of the T-lymphocyte-transforming HVS in its specificity for association with cdk6 and in its ability to strongly activate cdk6 protein kinase activity.

Comparative study of mouse heart and heart-lung transplantations

Heart transplantation in mice using a double anastomosis technique has become the standard method regardless of its technical difficulty. Heart-lung transplantation performed by single anastomosis in rats was also applied to mice, showing the identical operative result in addition to the advantage of easy applicability. We compared the heart transplant made by double anastomosis with the heart-lung transplantation using single aortic anastomosis in terms of graft survival and histologic features. The results were as follows: 1) During the follow-up period of 100 days after the transplantation in mice that survived 7 days after the operation, there were no deaths among the hosts and no evidence of nonfunction of the grafts in the six mice in each group. 2) In terms of monocyte infiltration perivascularily or interstitially, myocyte necrosis, interstitial hemorrhage, neutrophilic infiltration, and endocardial changes, histologic changes in the grafts were less in single anastomosis of heart-lung transplants than in double anastomosis. As a result, we can deduce that heart-lung transplantation using the single anastomosis technique is a good experimental model for the study of transplant reaction.