[Risks to predict blood loss and cranial nerve injury in carotid body paraganglioma resection].

Objective: To investigate clinical and imaging parameters to predict blood loss and cranial nerve injury (CNI) following carotid body paraganglioma (CBP) resection. Methods: A retrospective examination of clinical and imaging data was conducted on 63 patients who underwent CBP resection at Xiangya Hospital of Central South University from January 2016 to December 2022, including 23 males and 40 females, aged 26-87 years old. Three imaging parameters including tumor volume, the angle of contact with the internal carotid artery (ICA), and the distance to the base of skull (DTBOS) were gauged using the IMEDPACS software on CTA and MR imaging. The predictive efficacies of age, gender, Shamblin classification, and three imaging parameters for blood loss and CNI following surgery were analysed. Logistic composite parameter models were constructed and their predictive validity was assessed. Results: Multivariate logistic regression analysis underscored that only tumor volume (OR=1.381,95%CI:1.167-1.507,P=0.001) showed significant statistical correlations with blood loss following surgery. Area under curve (AUC) values of 0.910 for receiver operating characteristic (ROC) curves showed a sensitivity of 1.000 and a specificity of 0.694. Tumor volume (OR=1.126,95%CI:1.030-1.231, P=0.002) and DTBOS (OR=0.225,95%CI:0.081-0.630,P=0.005) were significantly associated with postoperative CNI. The analysis of logistic composite model showed AUC values for tumor volume, DTBOS and combination of the two parameters were 0.858, 0.788, and 0.872, respectively. The model for combination of tumor volume and DTBOS also proved superior in predicting postoperative CNI (Z=3.106, P<0.001), with a sensitivity of 0.833 and a specificity of 0.769. Conclusions: Tumor volume and DTBOS emerged as effective predictors for blood loss and/or CNI in patients with CBP resection. Moreover, the logistic composite parameter model outclassed single-parameter models in terms of their predictive clinical value.

[Clinical effects of transplantation of turbocharged bipedicle deep inferior epigastric perforator flap in breast reconstruction].

Objective: To explore the clinical effects of transplantation of turbocharged bipedicle deep inferior epigastric perforator (DIEP) flap in breast reconstruction. Methods: A retrospective observational study was used. From December 2008 to December 2016, 24 patients who met the inclusion criteria were treated in the Department of Plastic Surgery of Hunan Cancer Hospital, all patients were female, aged 28-51 (36.5±1.6) years. All cases received turbocharged bipedicle DIEP flap for two-staged breast reconstruction. According to the patterns of turbocharged vessels anastomosis, the turbocharged bipedicle DIEP flaps with length of (27.5±0.3) cm and width of (12.8±1.4) cm, were divided into three types: distal end of pedicle anastomosis type, main branch of pedicle anastomosis type, and muscular branch of pedicle anastomosis type. After complete hemostasis in the donor region, the anterior sheath was repaired with intermittent suture, and umbilical reconstruction was completed. Two negative pressure drainage tubes were indwelled, and subcutaneous tissue and skin were sutured layer by layer. The specific ways of vascular anastomosis of the flap pedicle with the internal thoracic vessels of recipient site included anastomosing the proximal end of one artery and one vein, anastomosing the proximal and distal end of one artery and one vein, and anastomosing the proximal end of one artery and two veins. Postoperatively, the survival and blood supply of flaps were observed. The patients were followed up to observe the reconstructed breast shape satisfaction, donor site complications, abdominal wall function, and scar hyperplasia. Results: All turbocharged bipedicle DIEP flaps for two-staged breast reconstruction survived well, with good blood supply. During follow-up for 14 to 56 (20±6) months, the shape of reconstructed breasts was satisfied. Only linear scar was left in the donor sites of abdomen with no complications, and the function of abdominal wall was not affected. Conclusions: For patients with clear indications, transplantation of free turbocharged bipedicle DIEP flap is a safe, reliable, and satisfactory choice for breast reconstruction with autologous tissue.

[Application of a small drainage tube in transoral endoscopic thyroidectomy vestibular approach].

Objective: To examine the feasibility of small drain in transoral endoscopic thyroidectomy vestibular approach (TOETVA). Methods: A prospective research was performed in Department of Oncology Plastic Surgery/Head and Neck Surgery, Hunan Cancer Hospital, from October 2018 to March 2019. Totally 103 patients who met the inclusion and exclusion criteria, signed the operation agreement of TOETVA, had their surgery completed and followed-up over 6 months, were enrolled in analysis. A central venous catheter was used as a drain tube in all cases (outer diameter 1.7 mm, inner diameter 1.0 mm). Visual analogue scale (VAS) was applied for assessing pain scores during the first 24 hours after the operation. Vancouver scar scale (VSS) was used for assessing the scar left by the drainage. The drainage volume (minimum scale:10 ml, approximate read: 1 ml) was recorded every 2 hours during the first postoperative 12 hours, every 4 hours during 12 to 24 hours, every 8 hours during 24 to 48 hours, and once from 48 hours until extubation. The volume of drainage, the cumulative volume and the percentage of cumulative volume accounting for the total volume were calculated. The data of residual volume (subtract the cumulative volume from the total volume) in the postoperative 24, 32 and 40 hours were analyzed, and their upper one-side P(95) was calculated by percentile method. Results: There were 12 males and 91 females. The age was (36.6±9.7) years (range: 18 to 58 years). The intraoperative tube-inserting time was (10.1±2.6) minutes (range: 6 to 18 minutes). The pain score on the first day was 2.7±1.1 (range: 1 to 5). The extubation time was (2.7±0.5) days (range: 2 to 4 days). VSS scores in the postoperative 1(st) month and 6(th) month were 2.9±1.3 (range: 0 to 7) and 0(2)(M(Q(R))), respectively. The size of the scar was 0 (2.5) mm in the postoperative 6(th) month. Sixty-four patients had no visible scars. There were 5 patients who had postoperative drain-related complications (1 for air leakage, 1 for tube blockage, 3 for subcutaneous hydrop, 2 for regional infection), who were all cured after proper treatment. The total volume of drainage for 98 patients without postoperative drain-related complications was (80.1±12.2) ml (range: 58 to 131 ml). The cumulative drainage within 8 hours accounted for (53.8±4.2)% (range: 41.0% to 62.9%) of the total drainage. The volume of residual fluids in the postoperative 32 hours was estimated to (5.8±2.7) ml (range: 0 to 12 ml,P(95)=10.0 ml). Conclusions: The small drain tubecan be applied in TOETVA, providing a satisfied cosmetic appearance and a reliable drainage. The main exudation period of the wound is within 8 hours after the operation. If a residual volume less than 10 ml is considered to be self-absorbable, the shortest safe extubation point for 95% patients without drain-related complications should be 32 hours after the operation.

[A case of using profunda artery perforator flap as an intraoperative salvage for failed deep inferior epigastric artery perforator flap harvesting in autologous breast reconstruction].

On April 11, 2019, a 36-year-old female patient was admitted to Hunan Cancer Hospital. Five years after the modified radical mastectomy for right breast cancer, she planned to undergo scar releasing and reconstruction of right chest wall and free deep inferior epigastric artery perforator (DIEP) flap transfer, right breast reconstruction, and left breast mastopexy. The defect of right chest wall after scar resection was 18 cm×10 cm. During the operation, the vascular pedicle of DIEP flap was accidentally injured, then the profunda artery perforator flap in left inner thigh was designed for salvage. The size of the flap was 20 cm×11 cm, the thickness was 4.5 cm, the length of perforator vessel pedicle was 7.6 cm, and the weight of the flap was 360 g. The right breast defect was repaired with the transferred flap and the deep cavity was filled. The vascular pedicle of profunda artery was anastomosed with the proximal end of the right internal mammary artery. The blood supply of the flap was good during surgery. The left breast mastopexy was completed at the same time, and the donor site of thigh and abdomen was closed directly. The flap survived well and the donor site healed well after surgery. During the follow-up of 7 months post surgery, the appearance and function of thigh donor site were good, no obvious complications were found, and the reconstructed breast was smaller than the contralateral side. This case suggests that the profunda artery perforator flap could be a valuable option as an alternative for DIEP harvesting failure for autologous breast reconstruction.

[Anatomical classification and application of chimeric myocutaneous medial thigh perforator flap in head and neck reconstruction].

Objective: To explore the anatomical classification and application of chimeric myocutaneous medial thigh perforator (MTP) flap in head and neck reconstruction. Methods: From September 2015 to December 2018, the clinical data of 74 patients (62 males and 12 females, age ranging from 31 to 69 years, with a mean age of 50.2 years) with oral tumor, who underwent radical resection in Hunan Cancer Hospital, including 39 cases of tongue carcinoma, 24 cases of gingival carcinoma and 11 cases of buccal cancer, 26 cases of stage T4N1M0, 22 cases of stage T4N0M0,15 cases of stage T3N1M0, and 11 cases of stage T3N2M0 were retrospectively analyzed in this work.The arteries and the veins contributing to MTP were anastomosed respectively with superior thyroid arteries, while the venae comitans were anastomosed with superior thyroid venae veins or internal jugular venae vein. The size of soft tissue defect, the length, width and thickness of free medial thigh flap, the length and source of vascular pedicle were recorded. The flap survival, functional status and donor area recovery were observed. Results: The postoperative defects in size ranged from 4.0 cm×3.5 cm to 9.0 cm×5.5 cm, which were reconstructed by free chimeric myocutaneous MTP flaps. The mean length of MTP flaps was (12.5±0.4) cm, the mean width was (7.2±0.4) cm, the mean thickness was (3.5±0.2) cm. The mean pedicle length was (8.6±0.4) cm. The perforators existed consistently in all cases, and the vascular origins were classified into 6 types. There were 4 cases (5.4%) of the perforating branches originating from femoral artery between the medial femoris and the adductor longus, 6 cases (8.1%) of the perforating branches of the profunda femoral artery from the adductor longus, 16 cases (21.6%) of the perforating branches of the profunda femoral artery from the gracilis, 9 cases (12.2%) of the perforating branches of the profunda femoral artery between the gracilis and the adductor longus, 29 cases (39.2%) of the perforating branches of the profunda femoral artery from the adductor longus, and 10 cases (13.5%) of branches of the profunda femoral artery from the semimembranous muscle. All 74 flaps survived uneventfully. The donor sites and recipient sites were closed directly in all cases. All patients were followed up for 12-36 months with satisfied esthetic and functional results. Only linear scars were left in the donor sites, and the thigh function was not affected. Local recurrence happened in 4 cases, which were treated with radical resection and the left defects were reconstructed with pedicled pectoral major myocutaneous flaps. Conclusion: The chimeric myocutaneous MTP flap has good color match and texture, with abundant tissue, and consistent blood supply, and it can be harvested in various forms while leaving minimal morbidity at donor site, being an idea choice for reconstruction after surgery of oral cancer.

[Selection and effects of flap/myocutaneous flap repair methods for the defect after perineum tumor resection].

Objective: To explore the selection and effects of flap/myocutaneous flap repair methods for the defect after perineum tumor resection. Methods: From January 2011 to February 2017, 31 patients with vulvar tumor who were admitted to Hunan Cancer Hospital underwent repair of wound after tumor resection with various flaps/myocutaneous flaps. The patients were composed of 5 males and 26 females, aged 39-76 years, with 27 vulvar cancer and 4 Paget's disease in primary diseases. The size of defects after vulvar tumor radical resection ranged from 8.0 cm×4.5 cm to 27.5 cm×24.0 cm. According to the theory of perforasome, the defects were repaired by the external pudendal artery perforator flap, deep inferior epigastric artery perforator flap, rectus abdominis myocutaneous flap, anterolateral thigh flap, internal pudendal artery perforator flap, gracilis myocutaneous flap, and profunda artery perforator flap based on the specific size and location of perineum and groin where the defect was located. According to the blood supply zone of flap, totally 17 local translocation flaps, 18 axial flaps/myocutaneous flaps, and 7 V-Y advancement flaps were resected, with an area of 7.0 cm×4.0 cm to 21.0 cm×13.0 cm. All the flaps/myocutaneous flaps were transferred in pedicled fashion, and the donor sites were closed without tension. The number of flaps/myocutaneous flaps, wound closure, flaps/myocutaneous flaps survival, and follow-up were observed and recorded. Results: Altogether 42 flaps/myocutaneous flaps were harvested in 31 patients. Two flaps/myocutaneous flaps were used in 11 cases for large circular defect repair. All the defects achieved tension-free primary closure. The blood supply of 32 flaps/myocutaneous flaps was good, while insufficient blood supply was noted in the other 10 flaps/myocutaneous flaps. Seventeen flaps/myocutaneous flaps survived smoothly. Wound dehiscence occurred in 5 flaps/myocutaneous flaps 8 to 14 days postoperatively, which was healed with dressing change. Temporary congestion was noted in 7 flaps/myocutaneous flaps 2 to 5 days postoperatively, which recovered without special treatment. Three flaps/myocutaneous flaps had infection 7 to 15 days postoperatively, two of which recovered after dressing change, while the other one had partial necrosis and received debridement and direct closure. Two flaps/myocutaneous flaps were totally necrotic 8 to 15 days postoperatively, which were repaired with pedicled rectus abdominis myocutaneous flap after debridement. Seven flaps/myocutaneous flaps had partial necrosis 7 to 20 days postoperatively and were healed after dressing change. Twenty-four patients were followed up for 9-38 months. The color of flaps/myocutaneous flaps was similar to that of the surrounding skin, the shape of vulva was natural, the movement of hip joint was not limited, the function of micturition and defecation was not affected, and tumor recurrence was noted in 3 patients. Conclusions: For the complicated large defect after perineum tumor resection, the flexible application of different forms of flaps/myocutaneous flaps to repair according to different areas regains the appearance and function. However, there are many complications, so it is necessary to further strengthen the postoperative care.

[Hepatotoxicity associated with tumor immune checkpoint inhibitors].

Although tumor immune checkpoint inhibitors therapy brings survival benefits to cancer patients, it also faces many challenges, such as the occurrence of immune-mediated hepatotoxicity. Therefore, an in-depth understanding of the conditions, possible mechanisms, and risk factors that cause liver injury during the treatment of tumor immune checkpoint inhibitors will facilitate better clinical management.

[Advances in the treatment of anterior commissure combined with early glottic carcinoma].

Summary Early glottic laryngeal cancer usually refers to the Tis-T2 lesion without cervical lymph node and distant metastases. Radiotherapy of early glottic laryngeal cancer, CO2 laser microsurgery, open surgery, plasma radiofrequency ablation, photodynamic therapy, biological targeting therapy have achieved good therapeutic effect. However, due to the special nature of its anatomy, it is controversial about the treatment of early glottic laryngeal cancer which involves the anterior commissure. In this article, we reviewed the conventional treatment of radiation therapy, CO2 laser microsurgery, open surgery, plasma radiofrequency ablation.

[Clinical application of modified bilobed chimeric thoracoacromial artery perforator flap for reconstruction of hypopharyngeal defect with anterior neck skin loss].

Objective: To evaluate the efficacy of modified bilobed chimeric thoracoacromial artery perforator (TAAP) flap for the reconstruction of hypopharyngeal defect with anterior neck skin loss. Methods: Between May 2013 and September 2015, modified bilobed chimeric TAAP flap was used to reconstruct complex oncologic hypopharyngeal defects in 7 patients, including 6 males and 1 female. Patients' age ranged from 28 to 65 years old (mean age 50±3.4 years old). The size of hypopharyngeal defect ranged from 5.5 cm×3.5 cm to 12.0 cm×4.5 cm, and the size of anterior neck defect ranged from 8.0 cm×4.0 cm to 10.0 cm×4.0 cm. Results: The size of TAAP flap was from 6.5 cm×4.0 cm to 13.0 cm×5.0 cm.The size of pectoralis major flap was from 8.0 cm×4.5 cm to 11.0 cm×5.0 cm. The length of pedicle was 6.5-8.5 cm.The distance from pivot point of flap to central point of recipient site was 7.0-9.5 cm.All flaps survived thoroughly, the donor site was closed directly in all cases.The mean hospital stay ranged from 14 to 19 days (mean 15.5 days). The follow-up was 14, 15, 20, 18, 30, 25 and 38 months respectively.Patient possessed good appearance of neck surgical sites, and oral diet was restored in all patients.No recurrence, fistula, stenosis/stricture, dehiscence, or swelling occurred, only with scars left on the donor sites, and pectoralis major muscle function was completely preserved in all patients. Conclusions: Modified bilobed chimeric TAAP flap is a good choice for the reconstruction of hypopharyngeal defect with anterior neck skin loss.

[Expression and significance of serum insulin-like growth factor-1 in patients with obstructive sleep apnea hypopnea syndrome].

Objective:To investigate the expression and significance of serum insulinlike growth factor-1(IGF-1) in adult patients with obstructive sleep apnea hypopnea syndrome(OSAHS).Method:One hundred and seven patients of OSAHS diagnosed with PSG were included in the observation group，which were divided into heavy, medium and light group according to AHI.Fifty case of healthy people without OSAHS were included in control group.Serum IGF-1 were measured by ELISA. Thirty patients of heavy OSAHS received surgery and CPAP treatment for three months,and were retested the levels of IGF-1 and PSG six months later.Result:①With the increase of OSAHS severity, the levels of serum IGF-1 were gradually decreased (F=37.732,P<0.01). There was no significant difference between mild group and healthy people (P>0.05), while there was significant differences between the remaining groups (P<0.01). ②Serum IGF-1 level has no correlation with BMI and age in OSAHS patients(P>0.05), and negatively correlated with LSaO2,and positively correlated with AHI (P<0.01). ③Serum IGF-1 levelï¼»(46.56±3.74)µg/Lï¼½ increased slightly compared with those before treatmentï¼»(42.79±4.87）µg/Lï¼½ in 30 severe patients after treatment with 3 months CPAP and regimen (P<0.01). Serum IGF-1 levelï¼»(56.61±5.46)µg/Lï¼½ increased significantly after treatment for six months; AHI level (18.72±7.36) was significantly lower than that before treatment (48.77±10.51), and LSaO2ï¼»(87.42±8.61)%ï¼½ increased significantly than that before treatmentï¼»(68.33±10.24)%ï¼½.Conclusion:OSAHS patients with decreased serum IGF-1 level may be associated with concurrent insulin resistance. Surgery combined with more than half a year of CPAP treatment can significantly reduce AHI, improve the level of LSaO2 and serum IGF-1. Serum IGF-1 levels could be used as a monitor of efficacy evaluation.

Impact of age on survival of locoregional nasopharyngeal carcinoma: An analysis of the Surveillance, Epidemiology, and End Results program database, 2004-2013.

OBJECTIVES: To determine the impact of age at diagnosis and other factors on survival in nasopharyngeal carcinoma (NPC). DESIGN, SETTING AND PARTICIPANTS: A retrospective, population-based cohort study of 3103 patients are selected, whose records were submitted to the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2013. We evaluated the demographic and clinical characteristics of patients who were 20 years or older with a diagnosis of primary, non-metastatic NPC. MAIN OUTCOME MEASURES: Overall survival (OS) and risks of OS and NPC-specific survival. RESULTS: Overall survival rates at 1, 3, and 5 years were 85.8%, 71.0%, and 62.6%, respectively. Older age was a significant predictor of poor OS, as was Chinese ethnicity. We also determined that middle-aged white patients, but not middle-aged black or Chinese patients, were at a higher risk of death than were younger patients of the same race/ethnicity. Nodal (N) stage 0-1 disease was a significant predictor of poor OS when comparing survival of older patients with N0-1 vs N2-3 stage disease. Finally, we found that married patients had a decreased risk of death when compared to those who were single. CONCLUSIONS: The survival of older patients with NPC is inferior to that of younger patients. Race/ethnicity, marital status, and stage of disease are important modifiers of risk. Collectively, our results indicate that management of older patients requires optimisation.

Circulating cell-free DNA in serum as a biomarker for diagnosis and prognostic prediction of colorectal cancer.

BACKGROUND: To verify whether the concentrations and integrity index of circulating cell-free DNA (ccf-DNA) in serum may be clinically useful for the diagnosis and progression monitoring of colorectal cancer (CRC) patients. METHODS: Serum samples were collected from 104 with primary CRC, 85 with operated CRC, 16 with recurrent/metastatic CRC, 63 patients with intestinal polyps and 110 normal controls. Long (247 bp) and short (115 bp) DNA fragments in serum were detected by real-time quantitative PCR by amplifying the ALU repeats (ALU-qPCR). Serum carcinoembryonic antigen (CEA) level was detected by ARCHITECT assay. RESULTS: The median absolute serum ALU115 and ALU247/115 in primary CRC group was significantly higher than those in intestinal polyp and normal control groups (both P<0.0001), in recurrent/metastatic CRC was significantly higher compared with primary CRC (P=0.0021, P=0.0018) or operated CRC (P<0.0001, respectively) and during follow-up, ALU115 and ALU247/115 were increased before surgery and decreased significantly after surgery. CONCLUSIONS: Combined detection of ALU115, ALU247/115 and CEA could improve the diagnostic efficiency for CRC. Serum DNA concentrations and integrity index may be valuable in early complementary diagnosis and monitoring of progression and prognosis of CRC.

Bone mineral density and the risk of peripheral arterial disease in men and women: results from Mr. and Ms Os, Hong Kong.

Previous population studies have demonstrated an association between peripheral vascular disease and bone mineral density in women, but not in men. In a large prospective cohort of 3,998 Chinese men and women aged 65 to 92 years of age in Hong Kong, the association between peripheral vascular disease and bone mineral density was explored. Demographic and lifestyle information was obtained from face to face interviews using a standardized questionnaire. This included demographic information, medical history and lifestyle factors. Physical examination measurements included anthropometry and tibial and brachial systolic blood pressures. The ratio of the posterior tibial and brachial systolic blood pressures, the ankle/arm index, was used as a measure of peripheral arteriosclerosis in the lower extremities. Bone mineral density (BMD) at the total hip and spine (L1-L4) was measured by Hologic QDR-4500 W densitometers (Hologic, Inc., Waltham, Mass.). In this cross-sectional analysis, the ankle brachial index (ABI) was positively correlated with hip BMD (correlation coefficient=0.27; P<0.001). However, after adjustment for confounders, the correlation became much weaker (correlation coefficient=0.03; P<0.05). This showed that much of the relationship between ABI and BMD could be explained by other confounders. In multiple regression analysis, an increase in ABI of 1 SD of ABI was associated with an increase of 0.5% (95% CI: 0.02%, 0.9%) in hip BMD after adjusting for age, sex, body weight, smoking status, history of diabetes, cardiovascular diseases, use of thiazide diuretics, grip strength and physical activity. Although our study shows that peripheral vascular disease in the lower extremities may be associated with decreased bone mineral density, the association is weak especially after adjustment was made for confounders. This indicates that other factors may be contributing to the association between peripheral vascular disease and osteoporosis.

Energetic and functional contribution of residues in the core binding factor beta (CBFbeta ) subunit to heterodimerization with CBFalpha.

Core-binding factors (CBFs) are a small family of heterodimeric transcription factors that play critical roles in several developmental pathways, including hematopoiesis and bone development. Mutations in CBF genes are found in leukemias and bone disorders. CBFs consist of a DNA-binding CBFalpha subunit (Runx1, Runx2, or Runx3) and a non-DNA-binding CBFbeta subunit. CBFalpha binds DNA in a sequence-specific manner, whereas CBFbeta enhances DNA binding by CBFalpha. Recent structural analyses of the DNA-binding Runt domain of CBFalpha and the CBFbeta subunit identified the heterodimerization surfaces on each subunit. Here we identify amino acids in CBFbeta that mediate binding to CBFalpha. We determine the energy contributed by each of these amino acids to heterodimerization and the importance of these residues for in vivo function. These data refine the structural analyses and further support the hypothesis that CBFbeta enhances DNA binding by inducing a conformational change in the Runt domain.

Biophysical characterization of interactions between the core binding factor alpha and beta subunits and DNA.

Core binding factors (CBFs) play key roles in several developmental pathways and in human disease. CBFs consist of a DNA binding CBFalpha subunit and a non-DNA binding CBFbeta subunit that increases the affinity of CBFalpha for DNA. We performed sedimentation equilibrium analyses to unequivocally establish the stoichiometry of the CBFalpha:beta:DNA complex. Dissociation constants for all four equilibria involving the CBFalpha Runt domain, CBFbeta, and DNA were defined. Conformational changes associated with interactions between CBFalpha, CBFbeta, and DNA were monitored by nuclear magnetic resonance and circular dichroism spectroscopy. The data suggest that CBFbeta 'locks in' a high affinity DNA binding conformation of the CBFalpha Runt domain.

Overexpression, purification, and biophysical characterization of the heterodimerization domain of the core-binding factor beta subunit.

Core-binding factors (CBF) are heteromeric transcription factors essential for several developmental processes, including hematopoiesis. CBFs contain a DNA-binding CBF alpha subunit and a non-DNA binding CBF beta subunit that increases the affinity of CBF alpha for DNA. We have developed a procedure for overexpressing and purifying full-length CBF beta as well as a truncated form containing the N-terminal 141 amino acids using a novel glutaredoxin fusion expression system. Substantial quantities of the CBF beta proteins can be produced in this manner allowing for their biophysical characterization. We show that the full-length and truncated forms of CBF beta bind to a CBF alpha DNA complex with very similar affinities. Sedimentation equilibrium measurements show these proteins to be monomeric. Circular dichroism spectroscopy demonstrates that CBF beta is a mixed alpha/beta protein and NMR spectroscopy shows that the truncated and full-length proteins are structurally similar and suitable for structure determination by NMR spectroscopy.

[The loss-grief reaction and coping behavior of a mother whose child died of a brain tumor].

This is a study on the loss-grief reaction and coping behavior of a mother whose child died of brain tumor. The researcher used field methods to collect data and analyze observations of mother-nurse interaction. The results showed that this mother had self-blame depression, and guilt feelings and affected the whole family. With the help of nurses and various supportive resources the mother was finally able to go through the grieving process smoothly.

Cardiac output in Xenopus laevis tadpoles during development and in response to an adenosine agonist.

We test the hypothesis that the heart and arteries enlarge with increased cardiac output (CO) during development and volume overload. Transparent albino tadpoles of Xenopus laevis at stages 43-50 were anesthetized in 0.3-0.5 mM benzocaine. Areas and radii [maximum and minimum radius (Rmax and Rmin, respectively)] of the ventricle were measured in digitized video frames during the cardiac cycle. Stroke volume (SV) and CO were calculated from Rmax and Rmin. Maximal velocities of 3.4-microns fluorescent beads were measured in the aortic arches. Arterial pressure was estimated by the Landis method. During normal development, the radii of the ventricle and aortic arch diameters increased with lengths of tadpoles, and SV (0.7 microliters/g) and CO (70 microliters.g-1.min-1) with wet weights. Volume overload was induced by a vasodilatory adenosine agonist 5'-N-ethylcarboxamidoadenosine (NECA) in the aquarium water. Acute (0.5-4 h) NECA significantly increased Rmax and heart rate. Chronic (> 1 wk) NECA significantly increased both Rmax and Rmin. SV and CO increased more than two times, blood pressures decreased, and specific vascular conductances increased more than five times. It is concluded that NECA increases CO in Xenopus tadpoles through a combination of increased filling and accelerated growth.