Use of free flaps with supermicrosurgery for oncological reconstruction of the maxillofacial region

Supermicrosurgery involves the dissection and anastomosis of vessels<0.8 mm in diameter with minimal donor site morbidity. This study evaluated the feasibility and outcomes of free flaps using supermicrosurgery to repair oncological defects in the maxillofacial region. Forty-two patients were treated with supermicrosurgery to repair oncological defects in the maxillofacial region between December 2015 and February 2021. The supermicrosurgery technique was used for different types of free flap, including 24 superficial circumflex iliac artery perforator flaps, seven anterolateral thigh flaps, three peroneal artery perforator flaps, five medial femoral condyle osteo-adipofascial flaps, and three profunda artery perforator flaps. An artery-to-artery approach was used in 38 patients; venous grafts for anastomosis were used in four patients to resolve an arterial discrepancy. Forty-one flaps (97.6%) survived. Thirty-six patients (85.7%) healed without any complications; three flaps required revision surgery including one lost, one demonstrated wound dehiscence, and two demonstrated wound infection. Supermicrosurgery is a useful complement to conventional microsurgery in head and neck reconstruction.

[Efficacy and prognostic analysis of 125I brathytherapy combined with chemotherapy for pediatric parameningeal rhabdomyosarcoma]

Objective: To analyze the efficacy and prognostic factors in children with parameningeal rhabdomyosarcoma (PMRMS) treated by ¹²⁵I brachytherapy combined with chemotherapy. Methods: A retrospective analysis of the clinical data of 33 pediatric patients treated with ¹²⁵I brachytherapy combined with chemotherapy in Peking University Stomatological Hospital from July 2013 to October 2018 was carried out to analyze the efficacy and prognostic factors. Results: Among the 33 patients, 19 were males and 14 were females; the median age was 4 years old (1-12 years old). There were 17 cases with embryonic type, 9 cases with alveolar type, and 7 with undifferentiated type; 26 cases with original PMRMS, and 7 cases with recurrent PMRMS. The tumors occurred in subtemporal-mastoid area in 15 patients, while nasopalatine-paranasal area in 6 cases, and parapharyngeal-submandibular area in 12 cases. There were 28 patients in IRS Ⅲ, and 5 patients in IRS Ⅳ. As for the risk level, 28 cases were in the middle-risk group and 5 cases in the high-risk group. The median follow-up time was 52 months. The 1, 3, and 5-year local control rates were 87.9%, 58.6%, and 49.9%, and the 1, 3, and 5-year survival rates were 93.8%, 60.5%, and 47.5%, respectively. The 5-year local control rate and 5-year survival rate of 12 patients with the tumor in the parapharyngeal-submandibular area were 91.7% and 100%, respectively. The 5-year local control rate and 5-year survival rate of the 6 patients with tumor in the nasopalatine-paranasal area were both 83.3%. The 3-year local control rate and 3-year survival rate of the 15 patients with tumor in the subtemporal-mastoid area were 17.5% and 21.4%. The multivariate survival analysis using Cox proportional risk regression model showed that the tumor located in the subtemporal-mastoid area was an independent risk factor affecting the 5-year overall survival rate (HR=38.40, 95%CI: 4.87-302.52, P=0.001). Within 3 months after ¹²⁵I seed implantation, the incidence of acute radiotherapy adverse reactions in all patients was 84.8% (28/33). Twenty-one patients (63.6%) had a grade 1 acute radiotherapy reaction, and 7 cases (21.2%) had a grade 2 acute radiotherapy reaction. No acute radiotherapy adverse reactions of grade 3 or 4 occurred. Three months after ¹²⁵I seed implantation, the adverse reactions were significantly alleviated, and no adverse reactions of grade 3 or above such as skin ulcer or salivary gland fibrosis occurred, and no serious cranio-maxillofacial deformities occurred. Conclusions: ¹²⁵I seed brachytherapy combined with chemotherapy has a definite clinical effect in the treatment of children with parameningeal rhabdomyosarcoma. The prognosis of rhabdomyosarcoma in the parapharyngeal-submandibular area and nasopalatine-paranasal area is better than that in the subtemporal-mastoid area.

Venous superdrainage using superficial circumflex iliac vein in deep circumflex iliac artery perforator flap with iliac crest for oromandibular reconstruction

The deep circumflex iliac artery perforator flap with iliac crest (DCIAPF) is considered a favourable single-flap option for oromandibular reconstruction. The aim of this study was to evaluate the effectiveness of venous superdrainage using the superficial circumflex iliac vein (SCIV) in the DCIAPF for oromandibular reconstruction. The data of 22 patients (12 female, 10 male) aged 10-76 years (median 53 years) who underwent simultaneous oromandibular reconstruction with a DCIAPF were reviewed retrospectively. Eleven patients received the DCIAPF with SCIV for superdrainage (group A) and another 11 patients received the conventional single-pedicled DCIAPF flap (group B). No flap loss occurred in either group. Venous congestion due to relative venous insufficiency was significantly more frequent in group B (P=0.045). There was no significant difference in the incidence of partial flap necrosis and wound dehiscence, or in the total operation time between the two groups. Superdrainage using the SCIV has the potential to reduce the incidence of venous congestion due to relative venous insufficiency in DCIAPF used for oromandibular reconstruction.

Recurrent adamantinoma of the mandible

Adamantinoma is an extremely rare tumour originating from bone that can be divided into classical and osteofibrous dysplasia (OFD)-like adamantinoma. This low-grade malignancy almost exclusively occurs in long bones, and only few cases of mandibular adamantinoma have been reported. Here, we report the case of a 30-year-old female with a 2-year history of right mandible tenderness. Radiological examinations showed a lytic lesion involving the right mandible without a well-defined margin. Biopsy confirmed the diagnosis of adamantinoma. She underwent a segmental mandibulectomy and reconstruction with a fibula flap. The definitive diagnosis was OFD-like adamantinoma. However, the tumour recurred after 5 years. The residual mandible and fibula flap were widely involved. A total mandibulectomy was performed. Five years later, there is no evidence of recurrence or metastasis. We recommend that adamantinoma be treated by radical resection with clear margins, and long-term surveillance is necessary due to the likely high local recurrence rate and the potential for late tumour metastasis.

Comparison of outcomes using radiotherapy or brachytherapy after resection of primary adenoid cystic carcinoma in oral and maxillofacial regions

We wished to investigate the outcome of surgery combined with external-beam radiotherapy (EBRT) or brachytherapy (¹²⁵I seeds) for the treatment of primary adenoid cystic carcinoma (ACC) of the oral and maxillofacial region. Data of patients with primary ACC were reviewed retrospectively. Patients were divided into EBRT and brachytherapy groups. Wide tumor excision was done to achieve negative margins. Standard radiotherapy in the EBRT group was 60 Gy. A treatment-planning system was used to create implantation plans with a prescribed dose of 60-120 Gy and ¹²⁵I seeds were implanted postoperatively. Kaplan-Meier method and log-rank tests were used to analyze local control and survival. The median duration of followup was 66.1 and 46.8 months for the EBRT group and brachytherapy group, respectively. There was no significant difference in local control, control of metastasis to regional lymph nodes, or control of distant metastasis between the two groups. There was no significant difference in overall survival, disease-specific survival, or disease-free survival in the two groups at 3 years and 5 years. The prevalence of complications in the brachytherapy group was lower than that in the EBRT group. Both methods elicited good treatment effects, but the prevalence of adverse events was lower in the brachytherapy group.

Resveratrol alleviates osteoporosis through improving the osteogenic differentiation of bone marrow mesenchymal stem cells

OBJECTIVE

To investigate the protective effect of Resveratrol (RES) on TNF-α-induced inhibition of osteogenic differentiation, thus alleviating the progression of osteoporosis (OP).

MATERIALS AND METHODS

OP model in rats was first conducted by performing ovariectomy (OVX). Rats were randomly divided into sham group, OVX group, and RES+OVX group. Body weight of each rat was regularly recorded every week. Bone mineral density (BMD) of rat femoral metaphysis was measured by micro-CT. Changes in radial degrees and loads of rat femora were examined through three-point bending experiments. Relative levels of OCN and Runx2 in each group were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Alkaline phosphatase (ALP) activity and calcification ability were assessed through ALP staining and alizarin red staining, respectively. Bone mesenchymal stem cells (BMSCs) were extracted from healthy rats and divided into control group, Tumor necrosis factor-α (TNF-α) group, RES group, and TNF-α+RES group based on different treatments. Relative levels of OCN and Runx2, ALP activity, and calcification ability in each group were detected in the same way. Finally, protein levels of NF-κB and β-catenin in BMSCs were determined.

RESULTS

Rats in each group gained body weight during the experimental period, especially those in OVX group and RES+OVX group. No significant difference in the body weight was found between OVX group and RES+OVX group. BMD in rat femora of RES+OVX group was higher than in OVX group but lower than sham group. Elastic/max radial degree and elastic/max load of femora were markedly reduced in OVX group compared to RES+OVX group. Relative levels of OCN and Runx2, ALP activity and calcification ability decreased in OVX group relative to sham group, which were partially reversed by RES treatment. After osteogenic differentiation in BMSCs induced with TNF-α, viability and calcification ability were markedly reduced and were upregulated by RES treatment. Moreover, RES treatment enhanced the downregulated levels of OCN and Runx2 in BMSCs undergoing TNF-α induction. Upregulated protein levels of nuclear factor kappa-B (NF-κB) and β-catenin in TNF-α-induced BMSCs were downregulated by RES treatment.

CONCLUSIONS

The inhibited osteogenic differentiation of BMSCs undergoing TNF-α induction is improved by resveratrol treatment, which contributes to alleviate the progression of osteoporosis.

Anti-IFNAR treatment does not reverse neuropsychiatric disease in MRL/lpr lupus mice

OBJECTIVE

Many systemic lupus erythematosus patients display a type I interferon (IFN) signature, and IFNα levels positively correlate with disease severity. Previous studies blocking the type I IFN pathway systemically in lupus models showed some beneficial effects. However, its effects on neuropsychiatric manifestations have yet to be carefully assessed, even though IFNα has been associated with induction of depression. Our aim was to investigate whether disrupting the type I IFN pathway would attenuate the development of murine neuropsychiatric lupus.

METHODS

Female MRL/lpr mice were administered an antitype I IFN receptor (IFNAR) antibody or a control antibody intraperitoneally three times weekly for 12 weeks starting at age 4-5 weeks. Behavior was assessed during and at the end of the treatment schedule.

RESULTS

No significant differences were seen between the anti-IFNAR- and control-treated mice when assessing for depression-like behavior or cognitive dysfunction, although anti-IFNAR antibody-treated mice displayed significant decreases in levels of IFN-stimulated genes. Anti-IFNAR treatment also did not significantly improve brain histology, cellular infiltration, or blood-brain barrier integrity.

CONCLUSIONS

Surprisingly, our results showed no improvement in neuropsychiatric disease and suggest that the role of IFNAR signaling in the pathogenesis of neuropsychiatric lupus continues to need to be carefully assessed.

[Study of surgery combined with 125I brachytherapy for adenoid cystic carcinoma of oral and maxillofacial region]

OBJECTIVE

To retrospectively analyze the results of treatment outcome by surgery combined with ₁₂₅I brachytherapy and correlative factors of adenoid cystic carcinoma (ACC).

METHODS

In the study, 75 patients with primary ACC of oral and maxillofacial region were treated by surgery combined with ₁₂₅I seeds brachytherapy. Radical resection or subtotal resection was applied for the tumor. The brachytherapy treatment planning system was used to create implant plans with the prescribed dose of 60 Gy to 120 Gy. The ₁₂₅I seeds were implanted intraoperatively or postoperatively. The regular follow-up was required. The Kaplan-Meier method was used to assess the tumor control rate and the patients' survival rates. Meanwhile, the Cox regression analysis was used to find out the prognostic factors.

RESULTS

Local control rates at the end of 3 and 5 years were as follows: T1-T2, 92.2% and 82.0%; T3-T4, 82.6% and 82.6%; and overall, 90.0% and 78.8%. The disease-free survival rates were 74.9% and 54.3%, respectively. The overall survival rates for all the patients were 86.0% and 79.6%, respectively at the end of 3 and 5 years and were 91.3% and 91.3% for T1-T2 patients vs. 73.9% and 59.7% for T3-T4 patients. Distant metastasis-free survival rates at the end of 3 and 5 years were 84.4% and 76.7%, respectively. The distant metastasis-free survival rates at the end of 3 and 5 years were 83.4% and 79.6% with T1-T2 lesion compared with 86.0% and 67.8% with T3-T4 lesion. According to the COX univariate analysis and multivariate analysis, the risk of local recurrence would be raised by the age. Tumor stage and tumor site were the prognostic factors of the overall survival rates.

CONCLUSION

₁₂₅I brachytherapy conducted as an adjuvant therapy postoperatively of ACC of oral and maxillofacial region can acquire satisfactory localregional control, distant metastasis-free survival, disease-free survival and overall survival. Tumors are prone to recur on the older patients. Patients having advanced tumor stage or tumor located in the nasal cavity or sinuses will suffer lower survival rates.

[Simulation of dose distribution in bone medium of 125I photon emitting source with Monte Carlo method]

OBJECTIVE

To present a theoretical analysis of how the presence of bone in interstitial brachytherapy affects dose rate distributions with MCNP4C Monte Carlo code and to prepare for the next clinical study on the dose distribution of interstitial brachytherapy in head and neck neoplasm.

METHODS

Type 6711,¹²⁵I brachytherapy source was simulated with MCNP4C Monte Carlo code whose cross section library was DLC-200. The dose distribution along the transverse axis in water and dose constant were compared with the American Association of Physicists in Medicine (AAPM) TG43UI update dosimetry formalism and current literature. The validated computer code was then applied to simple homogeneous bone tissue model to determine the affected different bone tissue had on dose distribution from ¹²⁵I interstitial implant.

RESULTS

¹²⁵I brachytherapy source simulated with MCNP4C Monte Carlo code met the requirements of TG43UI report. Dose rate constant, 0.977 78 cGy/(h×U), was in agreement within 1.32% compared with the recommended value of TG43UI. There was a good agreement between TG43UI about the dosimetric parameters at distances of 1 to 10 cm along the transverse axis of the ¹²⁵I source established by MCNP4C and current published data. And the dose distribution of ¹²⁵I photon emitting source in different bone tissue was calculated. Dose-deposition capacity of photons was in decreasing order: cortical bone, spongy bone, cartilage, yellow bone marrow, red bone marrow in the same medium depth. Photons deposited significantly in traversal axis among the phantom material of cortical bone and sponge bone relevant to the dose to water. In the medium depth of 0.01 cm, 0.1 cm, and 1 cm, the dose in the cortical bone was 12.90 times, 9.72 times, and 0.30 times of water respectively.

CONCLUSION

This study build a ¹²⁵I source model with MCNP4C Monte Carlo code, which is validated, and could be used in subsequent study. Dose distribution of photons in different bone medium is not the same as water, and its main energy deposits in bone medium surface, so we should consider the effect of bone medium when we design the target area adjacent to the bone tissue in ¹²⁵I sources implantation plan.

The application of individual virtual nostalgic game design to the evaluation of cognitive function

The aim of this study was to develop a task set based on personalized material for nostalgic experience, which could detect cognitive ability via a virtual experience system combined with Kinect somatosensory interactive operation applications without the user wearing any accessory input device. Fifty-nine subjects participated in the experiment. The receiver operating characteristic curve of the game system was statistically analyzed for determining the best cutoff-point in the cognitive function assessment. Correlation analysis and regression analysis were used to explore the correlations between the results and the clinical cognitive assessment scales. According to the MoCA scores, the results showed that the accuracy of the system was 86.4% in evaluating mild cognitive impairment. The system seems feasible and was strongly correlated with clinical cognitive assessment scales. We anticipate that daily use of our system could keep track of changes of cognitive function of the elderly in home life.

Nineteen polymorphic microsatellite markers developed for Trachinotus ovatus

To evaluate the population genetic diversity of the ovate pompano, we isolated and characterized 19 microsatellite markers using a (CA)13-enriched genomic library. Polymorphism was assessed in 30 individuals from a single population collected from the Daya Bay Aquaculture Center, Guangdong, China. The number of alleles per locus ranged from 2 to 18 with an average of 7.8. The observed and expected heterozygosities varied from 0.2667 to 1.000 and from 0.3960 to 0.9435, respectively. Sixteen of 19 loci conformed to Hardy-Weinberg equilibrium, and no significant linkage disequilibrium was detected between any locus pairs. Our study supplies candidate microsatellite markers that can be useful for studying the population genetic structure of ovate pompano.

Submental cutaneous sinus tract of mandibular second molar origin

AIM

To report a case in which a submental cutaneous sinus tract resulted from apical periodontitis associated with a mandibular second molar.

SUMMARY

A 53-year-old man presented with a chronic cutaneous sinus tract in the submental region, which had previously been misdiagnosed as a thyroglossal fistula. The origin of the sinus tract was shown by sinus tract angiography to be the left mandibular second molar (tooth 37), which had apical periodontitis. The sinus tract healed after extraction of the tooth and partial excision of the lesion from an extraoral approach. Histological examination confirmed that the tract was lined with granulation tissue and not with epithelial tissue. A submental sinus tract drainage pathway was observed. Prompt dental evaluation, especially of all mandibular teeth, should be considered when assessing cases of submental cutaneous sinus tracts.

KEY LEARNING POINTS

An odontogenic origin should be part of the differential diagnosis for orofacial skin lesions. Cutaneous sinus tracts of mandibular molar origin are complex and thus a comprehensive examination should be stressed. It is necessary to examine all mandibular teeth in cases of odontogenic submental cutaneous sinus tracts. Sinus tract angiography can be used to identify the sinus tract pathway and to confirm the associated teeth. The treatment of an odontogenic cutaneous sinus tract requires the elimination of the source of infection.

125I brachytherapy alone for recurrent or locally advanced adenoid cystic carcinoma of the oral and maxillofacial region

BACKGROUND AND PURPOSE

This retrospective study was to evaluate the local control and survival of (125)I brachytherapy for recurrent and/or locally advanced adenoid cystic carcinoma (ACC) of the oral and maxillofacial region.

PATIENTS AND METHODS

A total of 38 patients with recurrent and/or locally advanced ACC of the oral and maxillofacial region received (125)I brachytherapy alone from 2001-2010. Twenty-nine were recurrent cases following previous surgery and radiation therapy. The other 9 cases involved primary tumors. Overall, 12 tumors were located in the major salivary glands, 12 in the minor salivary glands, and 14 in the paranasal region, the nasal cavity or the skull base. The prescribed dose was 100-160 Gy.

RESULTS

Patients were followed for 12-122 months (median 51 months). The 2-, 5-, and 10-year local tumor control rates were 86.3, 59, and 31.5 %, respectively. The 2-, 5-, and 10-year overall survival rates were 92.1, 65 and 34.1 %, respectively. Tumors > 6 cm had significantly lower local control and survival rates. No severe complications were observed during follow-up.

CONCLUSION

(125)I brachytherapy is a feasible and effective modality for the treatment of locally advanced unresectable or recurrent ACC.

Enhanced secretion of IFN-gamma by activated Th1 cells occurs via reverse signaling through TNF-related activation-induced cytokine

Growing evidence has demonstrated that members of TNF superfamily transduce signals after engagement with their receptors. TNF-related activation-induced cytokine (TRANCE), a member of TNF superfamily, is preferentially expressed on the surface of activated CD4(+) Th1 cells. The soluble receptor activator of NF-kappaB (RANK).Fc fusion protein suppresses IFN-gamma secretion by activated Th1 cells, but does not affect IL-4 secretion by Th2 cells. The suppressive effect on IFN-gamma secretion is observed when Th1 cells are activated by APCs, but not by immobilized anti-TCR beta mAb. In contrast, immobilized RANK.Fc fusion protein augments IFN-gamma secretion by Th1 cells, indicating the occurrence of reverse signaling through TRANCE during T cell/APC interaction. The enhanced secretion of IFN-gamma mediated via TRANCE correlates with the activation of p38 mitogen-activated protein kinase and is blocked by SB203580, a p38 mitogen-activated protein kinase-specific inhibitor. Thus, in addition to its role in activating dendritic cells by binding to the receptor RANK, TRANCE itself can signal the augmentation of IFN-gamma secretion via a p38-dependent pathway, and this provides yet another example of reverse signaling by a member of TNF superfamily.

Coumarins and antiplatelet constituents from the root bark of Zanthoxylum schinifolium

Further study on the chloroform-soluble portion of the root bark of Zanthoxylum schinifolium led to the isolation of eight new coumarins: methylschinilenol (1), hydroxyepoxycollinin I (2), 8-methoxyanisocoumarin H (3), hydroxyschininallylol (4), hydroxyepoxycollinin II (5), schinitrienin (6), schininallylone (7), and isoschinilenol (8), along with twenty-six known compounds including fourteen coumarins, and nine alkaloids. The structural elucidation was determined by spectroscopic data. Among the isolates, terpenyl-coumarins and furoquinolines were the active constituents with antiplatelet aggregation in vitro and collinin (10) showed significant anti-HBC DNA replication activity.

Decreasing cyclic GMP exerts similar positive functional effects on cardiac myocytes regardless of initial level

We tested the hypothesis that lowering the level of cyclic GMP would have positive functional effects on isolated rabbit ventricular myocytes regardless of the basal cyclic GMP level. Cell shortening data were collected with a video detector; O(2) consumption data were obtained with a Clark electrode; intracellular cyclic GMP levels were obtained by radioimmunoassay. Data were obtained: (1) at baseline; (2) after the addition of 1H-[1,2,4]oxadiazolo[4, 3-alpha]quinoxaline-1-one (ODQ) 10(-6) and 10(-4) mol/l, a selective soluble guanylyl cyclase inhibitor, and (3) after zaprinast 10(-6) mol/l, a cyclic GMP phosphodiesterase inhibitor, followed by ODQ 10(-6) and 10(-4) mol/l. We found that ODQ 10(-4) mol/l significantly decreased the cyclic GMP level from 493 +/- 75 to 301 +/- 78 (fmol/100,000 myocytes) and increased percent shortening (Pcs, %; 4.9 +/- 0.3 vs. 5.8 +/- 0.6) and maximum rate of shortening (Rs, microm/s; 58.7 +/- 5.7 vs. 73.6 +/- 4.9). Zaprinast significantly increased the cyclic GMP level from 419 +/- 140 to 599 +/- 241 and decreased Pcs (6.2 +/- 0.5 vs. 4.4 +/- 0.4) and Rs (65.5 +/- 5.3 vs. 49.6 +/- 4.3). After zaprinast, ODQ 10(-4) mol/l decreased the cyclic GMP level to 439 +/- 139 and increased percent shortening and rate of shortening by a similar percentage compared to the non-zaprinast treated myocytes. We conclude that in rabbit ventricular myocytes, a reduction in the level of myocyte cyclic GMP increases myocyte function independent of the initial cyclic GMP level.

Opposing functional effects of cyclic GMP and cyclic AMP may act through protein phosphorylation in rabbit cardiac myocytes

1. We tested the hypothesis that the negative functional effects of cyclic GMP (cGMP) oppose the positive effects of cyclic AMP (cAMP) in cardiac myocytes through interaction at the level of their respective protein kinases. 2. Cell shortening was studied using a video-edge detector. The O2 consumption of a suspension of rabbit ventricular myocytes was measured using O2 electrodes. Protein phosphorylation was measured autoradiographically following SDS-PAGE. Data were collected with: (1) 8-bromo-cGMP (8-Br-cGMP) 10(-7) or 10(-5) M; (2) 8-bromo-cAMP (8-Br-cAMP) 10(-7) or 10(-5) M; (3) 8-Br-cAMP 10(-5) M followed by 8-Br-cGMP 10(-7) or 10(-5) M; (4) 8-Br-cGMP 10(-5) M followed by 8-Br-cAMP 10(-7) or 10(-5) M; (5) 8-Br-cGMP 10(-7) or 10(-5) M followed by KT 5720 (cAMP-dependent protein kinase inhibitor) or KT 5823 (cGMP-dependent protein kinase inhibitor) 10(-6) M; and (6) 8-Br-cAMP 10(-7) or 10(-5) M followed by KT 5720 or KT 5823 10(-6) M. 3. 8-Br-cGMP 10(-5) M decreased percent shortening (Pcs) from 6.3+/-0.6 to 3.6+/-0.4% and rate of shortening (Rs) from 66.7+/-4.4 to 41.8+/-4.2 microm s(-1). 8-Br-cAMP 10(-5) M increased Pcs (from 3.7+/-0.2 to 4.8+/-0.2) and Rs (from 50.0+/-3.0 to 60.0+/-3.1). With 8-Br-cAMP 10(-5) M, 8-Br-cGMP 10(-5) M decreased Pcs and Rs less. The positive functional effects of 8-Br-cAMP 10(-7) or 10(-5) M were also diminished with 8-Br-cGMP 10(-5) M. Following 8-Br-cGMP 10(-7) or 10(-5) M, KT 5720 10(-6) M further decreased Pcs to 2.5+/-0.3 and Rs to 30.0+/-4.1. KT 5823 10(-6) M returned Pcs to 4.7+/-0.4 and Rs to 61.3+/-5.3. Following 8-Br-cAMP 10(-7) or 10(-5) M, KT 5720 decreased the elevated Pcs and Rs significantly and KT 5823 10(-6) M further increased these parameters. 4. cGMP and cAMP phosphorylated the same five protein bands. With KT 5720 or KT 5823, all of the bands were lighter at the same concentration of 8-Br-cAMP and 8-Br-cGMP. 5. We conclude that, in rabbit ventricular myocytes, the opposing functional effects of cGMP and cAMP are related to the interaction at the level of their respective protein kinases.

Effects of beta-adrenoceptor stimulation on pacing-induced failure of dog hypertrophic hearts

1. We tested the hypothesis that the transition to pacing-induced failure in hypertrophic hearts would result in reduced functional and metabolic responses to beta-adrenoceptor stimulation. 2. Isoproterenol (ISO; 0.1 microg/kg per min) was infused into a coronary artery in five anaesthetized open-chest control, five aortic stenosis-induced left ventricular hypertrophy (LVH) and five LVH pacing-induced failure dogs. 3. In both control and LVH dogs, but not in failure dogs, ISO significantly increased local regional work (1,923+/-665 vs 2,656+/-715, 1,185+/-286 vs 1,906+/-562 and 835+/-106 vs 849+/-216g.mm/min, respectively), force (11.1+/-1.4 vs 16.9+/-2.6, 8.6+/-1.5 vs 13.7+/-2.3 and 12.2+/-1.1 vs 11.0+/-1.8g, respectively) and myocardial O2 consumption (7.3+/-2.0 vs 10.0+/-1.5, 8.2+/-1.6 vs 11.6+/-2.6 and 4.4+/-1.5 vs 5.5+/-1.8 mL O2/min per 100 g, respectively). 4. Isoproterenol also significantly increased cAMP in control and LVH dogs (474+/-67 vs 600+/-91 and 473+/-34 vs 619+/-53 pmol/g, respectively). In heart failure, cAMP was significantly lower and there was no significant increase in cAMP in response to ISO (245+/-43 vs 314+/-40pmol/g, respectively). 5. We conclude that there were no significant myocardial functional, O2 consumption or cAMP responses to ISO after the transition from hypertrophy to cardiac failure.

Down regulation of myocardial beta1-adrenoceptor signal transduction system in pacing-induced failure in dogs with aortic stenosis-induced left ventricular hypertrophy

We recently demonstrated that rapid ventricular pacing caused cardiac failure (Failure) in dogs with aortic stenosis-induced left ventricular hypertrophy (Hypertrophy) and isoproterenol caused no significant increases in function, O2 consumption and intracellular cyclic AMP level in the failing hypertrophied hearts. We tested the hypothesis that alterations in the beta1-adrenoceptor-signal transduction pathway would correlate with the reduced functional and metabolic responses to beta-adrenergic stimulation during the transition from the compensated hypertrophy to failure. Pressure overload-induced left ventricular hypertrophy was created using aortic valve plication in 10 dogs over a 6-month period. Five months after aortic valve plication, congestive heart failure was induced in 5 dogs by rapid ventricular pacing at 240 bpm for 4 weeks. The density of myocardial beta1-adrenoceptors (fmoles/mg membrane protein; fmoles/g wet tissue) was significantly reduced in the Failure dogs (176+/-19; 755+/-136) when compared to those of the Control (344+/-51; 1,551+/-203) and the Hypertrophy (298+/-33; 1,721+/-162) dogs. The receptor affinities were not significantly different among all groups. There was a small but significant decrease in the percentage of beta1-adrenoceptors of the failing hypertrophied hearts (62+/-3%) when compared to that of the hypertrophied hearts (77+/-5%). The basal myocardial adenylyl cyclase activity (pmoles/mg protein/min) was significantly lower in the Failure dogs (45+/-4) than in the Control (116+/-14) and Hypertrophy (86+/-6) dogs. The forskolin (0.1 mM)-stimulated adenylyl cyclase activity was also significantly lower in the Failure dogs (158+/-17) than in the Control dogs (296+/-35) and slightly lower than in the Hypertrophy dogs (215+/-10). There were no significant differences in low Km cyclic AMP-phosphodiesterase activities among all groups. We conclude that down regulation of beta1-adrenoceptors and reduced adenylyl cyclase activities contribute to the decreases in myocardial functions and beta-adrenergic responses in the failing hypertrophied hearts induced by rapid ventricular pacing.

Cyclic GMP reduces ventricular myocyte stunning after simulated ischemia-reperfusion

We tested the hypothesis that the second messenger activated by nitric oxide, cyclic GMP, would reduce the effects of myocyte stunning following simulated ischemia-reperfusion and that this was related to cyclic GMP protein kinase. Ventricular cardiac myocytes were isolated from New Zealand White rabbits (n = 8). Cell shortening was measured by a video edge detector and protein phosphorylation was determined autoradiographically after SDS gel electrophoresis. Cell shortening data were acquired at: (i) baseline followed by 8-Bromo-cGMP 10(-6) M (8-Br-cGMP) and then KT 5823 10(-6) M (cyclic GMP protein kinase inhibitor) and (ii) simulated ischemia (20 min of 95% N(2)-5% CO(2) at 37 degrees C) followed by simulated reperfusion (reoxygenation) with addition of 8-Br-cGMP 10(-6) M followed by KT 5823 10(-6) M, (iii) addition of 8-Br-cGMP prior to ischemia followed by the addition of KT 5823 10(-6) M after 30 min of reoxygenation. In the control group, 8-Br-cGMP 10(-6) M decreased percentage shortening (%short) (5.0 +/- 0.6 vs 3.8 +/- 0. 4) and the maximum velocity (V(max), microm/s) (48.6 +/- 6.9 vs 40.2 +/- 6.4). KT 5823 10(-6) M added after 8-Br-cGMP partially restored %short (4.6 +/- 0.5) and V(max) (46.6 +/- 8.0). After stunning, baseline myocytes had decreased %short (3.4 +/- 0.2) and V(max) (36. 0 +/- 4.2). After the addition of 8-Br-cGMP, the %short (2.7 +/- 0. 2) and V(max) (27.6 +/- 2.5) decreased further. The addition of KT 5823 did not change either the %short or the V(max). The myocytes with 8-Br-cGMP during ischemia had increased %short (4.2 +/- 0.2) and V(max) (37.2 +/- 3.4) when compared to the stunned group. The addition of KT 5823 did not significantly alter %short (3.3 +/- 0.4) or V(max) (29.2 +/- 5.0) in the myocytes pretreated with 8-Br-cGMP. Protein phosphorylation was increased by 8-Br-cGMP in control and stunned myocytes. KT 5823 blocked this effect in control but not stunned myocytes, suggesting some change in the cyclic GMP protein kinase. Ischemia-reperfusion produced myocyte stunning that was reduced when 8-Br-cGMP was added prior to but not after ischemia.

Pacing-induced cardiac failure of hypertrophic hearts: effects of cyclic GMP reduction

BACKGROUND

We tested the hypothesis that pacing-induced cardiac failure of hypertrophic hearts would reduce the functional and metabolic responses of these hearts to guanylate cyclase inhibition and this was associated with alterations in cyclic GMP.

MATERIALS AND METHODS

Methylene blue (MB, 2 mg/kg/min, guanylate cyclase inhibitor) was infused into the left anterior descending coronary artery in 5 control, 5 left ventricular hypertrophy (LVH), and 5 LVH pacing-induced failure dogs. Regional myocardial work was calculated as the integrated product of force and segment shortening and regional myocardial O(2) consumption (VO(2)) from coronary blood flow and O(2) extraction measurements. Cyclic GMP was determined by radioimmunoassay.

RESULTS

MB increased regional work (635 +/- 169 vs 1649 +/- 500, 781 +/- 184 vs 1569 +/- 203 g * mm/min) and VO(2) (8.3 +/- 1.4 vs 10.9 +/- 1.4, 7.3 +/- 0.7 vs 9.1 +/- 0.7 ml O(2)/min/100 g) in both control and LVH dogs but not in failure dogs (536 +/- 234 vs 623 +/- 193, 3.6 +/- 1.1 vs 4.7 +/- 1.9). MB also decreased cyclic GMP in control dogs (1170 +/- 142 vs 812 +/- 105 pmol/g). LVH dogs had elevated baseline cyclic GMP (5875 +/- 949) compared to control dogs but also demonstrated decreased cyclic GMP in response to MB (2820 +/- 372). In failure dogs, basal cyclic GMP was also elevated (4650 +/- 613) compared to control dogs but there was a lack of response to MB (3670 +/- 640).

CONCLUSIONS

We conclude that the myocardial function, VO(2) and cyclic GMP responses to methylene blue are diminished in the transition from hypertrophy to cardiac failure.

Uterine arteriovenous malformations: gray-scale and Doppler US features with MR imaging correlation

PURPOSE

To describe the gray-scale and color and duplex Doppler ultrasound (US) and the magnetic resonance (MR) imaging features of uterine arteriovenous malformations (AVMs).

MATERIALS AND METHODS

Uterine AVMs in 10 patients were retrospectively evaluated. All patients underwent gray-scale US and color and duplex Doppler US. Nine underwent angiography with therapeutic embolization; four, MR imaging. The resistance index (RI), pulsatility index (PI), and peak systolic velocities (PSVs) were evaluated.

RESULTS

At gray-scale US, uterine AVMs were nonspecific and manifested as subtle myometrial inhomogeneity, tubular spaces within the myometrium, intramural uterine mass, endometrial mass, or cervical mass or sometimes as prominent parametrial vessels. Color Doppler features were consistent and included intense juxtaposed signals with aliasing and apparent flow reversals. Spectral Doppler US revealed low-resistance flow (RI, 0.25-0.55; PI, 0.3-0.6) and PSVs greater than 96 cm/sec, which suggests arteriovenous shunting. MR imaging showed a bulky uterus, a focal uterine mass, disruption of the junctional zones, serpiginous flow-related signal voids, and prominent parametrial vessels.

CONCLUSION

Gray-scale morphology and Doppler US features should allow noninvasive diagnosis of uterine AVMs. Doppler and MR imaging features of uterine AVMs may overlap with other causes of arteriovenous shunting, including abnormal placentation and gestational trophoblastic disease (GTD). These can be differentiated with serum beta human chorionic gonadotropin test results (negative with AVM, positive with GTD).

Effect of estrogen on the serum level of thyroglobulin

Thyroglobulin has been widely accepted as a useful parameter for monitoring the recurrence of differentiated thyroid carcinoma. In thyroid cell cultures, it has been reported that estrogen may stimulate the tgb gene which controls synthesis of thyroglobulin by the thyroid follicular cell. Since the serum estrogen levels of women fluctuate during the menstrual cycle, pregnancy and menopause, thyroglobulin may be unreliable in the follow-up of recurrence of differentiated thyroid carcinoma in females if it can be affected by estrogen in vivo. In order to clarify the effect of estrogen on thyroglobulin, the sera of 16 men, 42 women and 20 children were collected and divided into seven groups. Their serum estradiol and thyroglobulin levels were 17.7 +/- 1.8 pg/mL (mean +/- SEM) and 17.1 +/- 1.6 ng/mL, respectively in 20 children, 26.7 +/- 4.1 pg/mL and 12.9 +/- 1.2 ng/mL, respectively in 16 males, 151.6 +/- 20.4 pg/mL and 13.7 +/- 4.2 ng/mL, respectively in five females on the 10th to 14th days of the menstrual cycle, 16.7 +/- 1.8 pg/mL and 15.2 +/- 2.1 ng/mL, respectively in 12 postmenopausal females, 530.0 +/- 131.0 pg/mL and 14.2 +/- 1.8 ng/mL, respectively in eight pregnant women in the first trimester, 3613.9 +/- 1014.2 pg/mL and 12.0 +/- 1.6 ng/mL, respectively in seven pregnant women in the second trimester and 9246.0 +/- 694.5 pg/mL and 16.4 +/- 2.0 ng/mL, respectively in 10 pregnant women in the third trimester. The serum estradiol levels were significantly different (p less than 0.005) among these seven groups, but the serum thyroglobulin levels were not (p = 0.25). Therefore, serum thyroglobulin levels are not affected by estrogen.(ABSTRACT TRUNCATED AT 250 WORDS)