P3540The predictive value of global longitudinal strain in patients with heart failure mid-range ejection fraction

Background

Heart failure with mid-range ejection fraction (HFmrEF) was defined as the typical symptoms of HF with a left ventricular ejection fraction (LVEF) of 41% to 49%. However, till now the progression of LV function and the subsequent prognosis remains largely unknown. Speckle tracking echocardiography (STE) is a novel method to detect the early myocardial dysfunction and has been used to differentiate the outcomes of different phenotypes of cardiovascular diseases.

Purpose

Herein, we aim to investigate the application of STE in HFmrEF and its predictive values.

Methods

Retrospectively, we collected the medical records and echocardiography imaging of 250 patients diagnosed as HFmrEF during 2014 to 2018. LV longitudinal strain at diagnosis was evaluated and compared with the changes of LV during the follow-up period. Also, mortality and major adverse cardiovascular events (MACE) including myocardial infarction, heart failure requiring admission were recorded.

Results

Our result indicated that a reduced LV longitudinal strain at baseline was significantly associated with a subsequent declined LVEF beneath 40%. Also, the lower strain a baseline implied the higher mortality and MACE. Using −12% as the cut-off value LV strain presented the most significant impact on the prognosis compared with the other echocardiographic parameters in the logistic regression Regarding the guideline directed medications, blockers of renin-angiotensin-aldosterone system most significantly improved the cardiac remodeling compared with the others.

Conclusion

STE can predict the subsequent changes of LVEF and the cardiovascular outcomes in patients with HFmrEF.

P1569The Impact of Multidisciplinary Cardio-Oncology Program on the Cardiovascular Outcomes in Breast Cancer Patients

Background

Chemo- and target therapies may induce myocardial dysfunction and lead to poor prognoses. Early detection of minor myocardial dysfunction is important for the prevention of subsequent cardiotoxicity. Cardio-oncology is a multidisciplinary field focusing on managing and preventing cardiovascular complications in cancer patients. However, whether Cardio-oncology program truly makes difference in cardiovascular outcomes remains unknown. Herein, we are sharing our experiences in our Medical Center.

Methods

Since 2014 till 2017, we recruited 154 patients with newly diagnosed breast cancer preparing for Epirubicin therapy. Echocardiography, biomarkers, six minute walking distance and cardiovascular adverse events including new onset of hypertension, stroke, myocardial infarction (MI) and mortality were recorded at baseline, three months, six months and one year. Any functional decline was reported to oncologists for the consideration of changing regimens. Otherwise, cardiologists would be consulted for cardiovascular educations and therapies. The echocardiographic and clinical records of 450 breast patients receiving Epirubicin therapy during 2010 to 2013 were also collected as comparison.

Results

Compared with the ratio of 20% patients receiving echocardiography prior to 2014, the ratio increased to 100% since Cardio-Oncology program started. Also, the drop of left ventricular ejection fraction (LVEF) from 25% attenuated to 5%. Before Cardio-Oncology Program, there were 1.7% of new onset hypertension, 0.8% of MI, 0.8% of stroke and 16.8% of mortality. Conversely, after the program, there were only 0.6% of new onset hypertension while no other cardiovascular complications were reported. Furthermore, compared with previous reports of the effectiveness of Cardio-Oncology Program, our result also displayed a superior impact on the cardiovascular outcomes.

Conclusions

Collectively, through a comprehensive monitoring and an early intervention of myocardial dysfunction post chemotherapies, Cardio-Oncology Program truly decreased the cardiovascular complications in breast cancer patients.

Acknowledgement/Funding

Chi-Mei Medical Center

Prognostic Performance of Current Stage III Oral Cancer Patients After Curative Intent Resection: Evidence to Support a Revision of the American Joint Committee on Cancer Staging System

BACKGROUND

The American Joint Committee on Cancer (AJCC) stage III classification of oral cavity squamous cell carcinoma (OCSCC) represents a heterogeneous group of patients with early local disease with regional metastases (T1N1 and T2N1) and advanced local disease with or without regional metastasis (T3N0 and T3N1).

OBJECTIVE

The aim of this study was to evaluate prognostic heterogeneity in the stage III category.

METHODS AND PATIENTS

An international retrospective multicenter study of 1815 patients who were treated for OCSCC from 2003 to 2011.

RESULTS

Kaplan-Meier survival analysis and multivariate models of stage III patients revealed better overall survival (OS; HR 2.12, 95 % CI 1.03-4.15; p = 0.01) and disease-specific survival (DSS; HR 1.7, 95 % CI 1.16-4.12; p = 0.04) rates for patients with T1-2N1/T3N0 disease than for patients with T3N1 disease. The outcomes of patients with T3N1 and stage IVa disease were similar (p = 0.89 and p = 0.78 for OS and DSS, respectively). Modifying stage classification by transferring the T3N1 category to the stage VIa group resulted in a better prognostic performance [Harrell's concordance index, C index 0.76; Akaike's Information Criterion (AIC) 4131.6] compared with the AJCC 7th edition staging system (C index 0.65; AIC 4144.9) for OS. When DSS was assessed, the suggested staging system remained the best performing model (C index 0.71; AIC 1061.3) compared with the current AJCC 7th edition staging (C index 0.64; AIC 1066.2).

CONCLUSIONS

The prognosis of T3N1 and stage IVa disease are similar in OCSCC, suggesting that these categories could be combined in future revisions of the nodal staging system to enhance prognostic accuracy.

Single nucleotide polymorphism variants within tva and tvb receptor genes in Chinese chickens

Avian leukosis is an immunosuppressive neoplastic disease caused by avian leukosis viruses (ALV), which causes tremendous economic losses in the worldwide poultry industry. The susceptibility or resistance of chicken cells to subgroup A ALV and subgroup B, D, and E ALV are determined by the receptor genes tumor virus locus A (tva) and tumor virus locus B (tvb), respectively. Four genetic resistant loci (tva(r1), tva(r2), tva(r3), and tva(r4)) in tva receptor gene and a genetic resistant locus tvb(r) in the tvb receptor gene have been identified in inbred lines of White Leghorn. To evaluate the genetic resistance to subgroup A, B, D, and E ALV, genetic variations within resistant loci in tva and tvb genes were screened in Chinese local chicken breeds and commercial broiler lines. Here, the heterozygote tva(s1/r1) and the resistant genotype tva(r2/r2), tva(r3/r3), and tva(r4/r4) were detected in Chinese chickens by direct sequencing. The heterozygote tva(s1/r1) was detected in Huiyang Bearded chicken (HYBC), Rizhaoma chicken, and commercial broiler line 13 to 15 (CB13 to CB15), with the frequencies at 0.08, 0.18, 0.17, 0.25, and 0.15, respectively. The resistant genotype tva(r2/r2) was detected in Jiningbairi chicken (JNBRC), HYBC, and CB15, with the frequencies at 0.03, 0.08, and 0.06, respectively, whereas tva(r3/r3) and tva(r4/r4) were detected in 19 and 17 of the 25 Chinese chickens tested, with the average frequencies at 0.13 and 0.20, respectively. Furthermore, the resistant genotype tvb(r/r) was detected in JNBRC, CB07, CB12, CB14, and CB15 by pyrosequencing assay, with the frequencies at 0.03, 0.03, 0.11, 0.09, and 0.15, respectively. These results demonstrated that the potential for genetic improvement of resistance to subgroup A, B, D, and E ALV were great both in Chinese local chickens and commercial broilers. This study provides valuable insight into the selective breeding for chickens genetically resistant to ALV.

Statistical inference for the within-device precision of quantitative measurements in assay validation

Intermediate precision is one of the most important characteristics for evaluation of precision in assay validation. The current methods for evaluation of within-device precision recommended by the Clinical Laboratory Standard Institute (CLSI) guideline EP5-A2 are based on the point estimator. On the other hand, in addition to point estimators, confidence intervals can provide a range for the within-device precision with a probability statement. Therefore, we suggest a confidence interval approach for assessment of the within-device precision. Furthermore, under the two-stage nested random-effects model recommended by the approved CLSI guideline EP5-A2, in addition to the current Satterthwaite's approximation and the modified large sample (MLS) methods, we apply the technique of generalized pivotal quantities (GPQ) to derive the confidence interval for the within-device precision. The data from the approved CLSI guideline EP5-A2 illustrate the applications of the confidence interval approach and comparison of results between the three methods. Results of a simulation study on the coverage probability and expected length of the three methods are reported. The proposed method of the GPQ-based confidence intervals is also extended to consider the between-laboratories variation for precision assessment.

Fluoroscopically guided percutaneous gastrostomy with modified gastropexy and a large-bore balloon-retained catheter in patients with head and neck tumors

PURPOSE

To report on fluoroscopically guided percutaneous gastrostomy (FPG) using a modified gastropexy technique with the insertion of a large-bore balloon-retained gastrostomy catheter in patients with head and neck tumors.

MATERIAL AND METHODS

Thirty-four patients with head and neck tumors underwent a modified gastropexy with two T-fasteners followed by the insertion of a 14-F ballooon-retained catheter through a peel-away introducer. The success rate and the complications of the procedures were evaluated at 14 days, 30 days, and 60 days. The complications were classified as: major complications that necessitated intensive and/or surgical treatment; minor complications that could be treated conservatively; and tube-related complications manageable by tube exchange.

RESULTS

FPG was technically successful in all cases. There were no major complications, two minor complications where superficial stoma infection was controlled by antibiotics, three minor tube-related complications, all three easily managed by catheter replacement via the original tract.

CONCLUSION

FPG with insertion of a large-bore balloon-retained catheter using a modified gastropexy technique is a safe and effective method that creates a feeding access for patients with head and neck tumors and esophageal obstruction. Minor complications can be managed conservatively. FPG may be a good alternative to surgical or percutaneous endoscopic gastrostomy.

Characteristics of mutations in the p53 gene in oral squamous cell carcinoma associated with betel quid chewing and cigarette smoking in Taiwanese

p53 mutations are etiologically associated with the development of oral squamous cell carcinomas (OSCCs) or are associated with exposure to specific carcinogens. In this study, we used PCR-single strand conformation polymorphism and DNA sequencing to analyze the conserved regions of the p53 gene (exons 5-9) in OSCC tumor specimens from 187 patients with varied histories of betel quid, tobacco and alcohol use. Ninety-one of the 187 OSCCs (48.66%) showed p53 gene mutations at exons 5-9. The incidence of p53 mutations was not associated with age, sex, TNM stage, status of cigarette smoking or betel quid chewing. However, alcohol drinkers exhibited a significantly higher incidence (57/101, 56.44%) of p53 mutations than non-users (39.53%, 34/86) (P = 0.02). The effect of alcohol on the incidence of p53 mutations was still statistically significant (RR = 2.24; 95% CI, 1.21-4.15) after adjustment for cigarette smoking and betel quid (BQ) chewing. G:C to A:T transitions were the predominant mutations observed and associated with BQ and tobacco use. Alcohol drinking could enhance these transitions. After adjustment for cigarette smoking and BQ chewing, alcohol drinking still showed an independent effect on G:C to A:T transitions (RR = 2.41; 95% CI, 1.01-5.74). These findings strongly suggest an important contributive role of tobacco carcinogens to p53 mutation in this series of Taiwanese OSCCs and alcohol might enhance these mutagenic effects. As safrole-DNA adducts have been detected in 77% (23/30) of the OSCC tissues from Taiwanese oral cancer patients with a BQ chewing history, we cannot rule out the possibility that safrole or other carcinogens present in the BQ may cause a similar pattern of mutagenesis. Determination of the role of safrole and other carcinogens present in BQ on the pattern of p53 gene mutation in OSCC will require further study.

Physiological adaptation of crop plants to flooding stress

When crop plants are subjected to soil waterlogging, or an anaerobic condition, their root and shoot systems respond differently. A variety of morphological and anatomical alterations develop in the root system. Reduction of the root respiration rate has been reported in both flooding-tolerant and intolerant species. Besides alcoholic fermentation, several diverse fermentative bypasses take place, which ameliorate the poisoning through excessive accumulation of specific metabolic intermediates. Root systems starved of oxygen are also poor providers of mineral nutrients for both themselves and the shoot systems. Stomatal closure and non-stomatal metabolic alterations are responsible for the reduction of leaf CO2 incorporation. Plant hormones are much involved in regulation of these physiological adaptations.

US-guided needle aspiration and catheter drainage as an alternative to open surgical drainage for uniloculated neck abscesses

PURPOSE

To prospectively evaluate the effectiveness of ultrasound (US)-guided needle aspiration and catheter drainage as an alternative to open surgical drainage of uniloculated neck abscesses.

MATERIALS AND METHODS

Fifteen consecutive patients (11 female, four male; age range from 18 days to 78 years, mean 42.5 y +/- 22.4) diagnosed with deep neck infections associated with uniloculated neck abscesses were treated. The patients were originally scheduled for surgical incision and drainage after a period of unsuccessful treatment with antibiotics. US-guided needle aspiration (in 10 patients) and US-guided catheter drainage (in five patients) were performed under local anesthesia. Open surgical drainage was performed when US-guided drainage procedures failed.

RESULTS

Surgical open drainage was avoided in 13 of the 15 patients (87%). An average of 6 mL of pus was obtained in patients in the needle aspiration group and 140 mL of pus was drained by catheter. One patient had a recurrent pyogenic lymphadenitis at the same location and was treated successfully by repeated needle aspiration. No complications occurred in this study.

CONCLUSION

In a selected group of patients without imminent airway obstruction, most uniloculated neck abscesses may be managed initially by US-guided needle aspiration and catheter drainage before resorting to open surgical drainage.

Poor prognosis in nasopharyngeal cancer patients with low glucose-6-phosphate-dehydrogenase activity

Nasopharyngeal carcinoma (NPC) is endemic among well-defined ethnic groups in several world regions, such as Southeastern China and Taiwan. Glucose-6-phosphate-dehydrogenase (G6PD)- deficiency, a sex-linked disorder, is one of the most common enzymopathies in Taiwan. The major role of G6PD is to generate NADPH to protect cells from oxidative damage, which is a major contributing factor to certain degenerative diseases, such as aging and cancer. In view of the coincidence of epidemic distribution of NPC and G6PD deficiency, as well as the house-keeping function of G6PD in cellular oxidative defense, we investigated the correlation of G6PD activity with NPC. The stage of NPC was classified by AJCC (1997) criteria. G6PD levels were determined in 108 NPC male patients and 75 healthy male individuals. The mean G6PD level of NPC patients was 218.9 U/10(12) RBC or 7.53 U/g hemoglobin (Hb), being much lower than in normal individuals (260.6 U/10(12) erythrocytes (RBC) or 8.92 U / gHb). The level of G6PD activity had no correlation with tumor stage or lymph node or distant metastasis, but was significantly correlated with tumor recurrence (P = 0.004 when using G6PD = 130 U/10(12) RBC as cutoff value). These results indicated that low G6PD activity in patients with NPC is associated with poor prognosis.

Structural and functional properties of a Bacillus subtilis temperature-sensitive sigma(A) factor

Bacillus subtilis DB1005 is a temperature-sensitive (Ts) sigA mutant containing double-amino-acid substitutions (I198A and I202A) on the hydrophobic face of the promoter -10 binding helix of sigma(A) factor. We have analyzed the structural and functional properties of this mutant sigma(A) factor both in vivo and in vitro. Our data revealed that the Ts sigma(A) factor possessed predominantly a multimeric structure which was prone to aggregation at restrictive temperature. The extensive aggregation of the Ts sigma(A) resulted in a very low core-binding activity of the Ts sigma(A) factor and a markedly reduced sigma(A)-RNA polymerase activity in B. subtilis DB1005, suggesting that extensive aggregation of the Ts sigma(A) is the main trigger for the temperature sensitivity of B. subtilis DB1005. Partial proteolysis, tryptophan fluorescence and 1-anilinonaphthalene-8-sulfonate-binding analyses revealed that the hydrophobic face of the promoter -10 binding helix and also the hydrophobic core region of the Ts sigma(A) factor were readily exposed on the protein surface. This hydrophobic exposure provides an important cue for mutual interaction between molecules of the Ts sigma(A) and allows the formation of multimeric Ts sigma(A). Our results also indicate that Ile-198 and Ile-202 on the hydrophobic face of the promoter -10 binding helix are essential to ensure the correct folding and stabilization of the functional structure of sigma(A) factor.

Telomerase activity is frequently found in metaplastic and malignant human nasopharyngeal tissues

Telomerase is a specialized ribonucleoprotein polymerase that directs the synthesis of telomere repeats at chromosome ends. Accumulating evidence has indicated that telomerase is stringently repressed in normal human somatic tissues but reactivated in cancers and immortal cells, suggesting that reactivation of telomerase plays an important role in carcinogenesis. In this study, the status of telomerase activity in diseased human nasopharyngeal lesions was determined by the telomeric repeat amplification protocol (TRAP). Fifty-four patients participated including 17 inflammation or hyperplasia, eight with squamous metaplasia, and 29 with different stages of carcinomas. Telomerase activity was detected in 1 of 17 (5.9%) inflammatory or lymphoid hyperplastic tissues, 3 of 8 (37.5%) squamous metaplastic, and 25 of 29 (86.2%) carcinoma tissues. The differences in telomerase expression in these groups is statistically significant (P < 0.001). Levels of telomerase activity correlated with tumour stage (P = 0.024). These results suggest that telomerase reactivation plays a role in the carcinogenesis of nasopharyngeal cancer. Since telomerase activity is found in the majority of nasopharyngeal cancers and a subset of metaplasia, this enzyme may be served as a reference to monitoring the status of abnormal nasopharyngeal tissues.

Locally recurrent nasopharyngeal carcinoma

PURPOSE

To assess the outcome of and determine prognostic factors for locally recurrent nasopharyngeal carcinoma (NPC) in patients treated with a second course of radiotherapy (RT).

MATERIALS AND METHODS

From 1982 to 1995, 186 NPC patients, who had initially been treated in the Department of Radiation Oncology, Chang Gung Memorial Hospital-Linkou, developed local recurrence in the nasopharynx and were re-treated with RT (>/=20 Gy). The time from the initial RT to re-treatment ranged from 8 to 136 months (median: 23 months). All patients were treated with external RT and conformal radiotherapy was used in 35 patients after 1993. Fifteen received radiosurgery as a boost treatment. The RT dose at the nasopharyngeal tumor area ranged from 20 to 67.2 Gy (median 50 Gy). Eighty-two patients received one to eight courses of cisplatin-based chemotherapy in addition to RT.

RESULTS

The 1-, 3- and 5-year survival was 54.9, 22. 1 and 12.4%, respectively. Patients whose tumor relapsed later than 2 years after the first treatment had a better survival than those with earlier relapse (3-year survival: 30.1 vs. 10.8%; P=0.015), but the difference became insignificant in patients who received >/=50 Gy. Patients without evidence of intracranial invasion or cranial nerve palsy had better survival than those with such lesions (3-year survival: 30.9 vs. 3.7%; P=0.006). A re-treatment dose >/=50 Gy yielded better survival (3-year survival: 22.8 vs. 18.5%; P=0.003). Addition use of radiosurgery may improve survival. The use of chemotherapy did not improve survival. Conformal radiotherapy resulted in significantly fewer severe complications than conventional RT.

CONCLUSIONS

A repeat course of RT for locally recurrent NPC successfully prolongs survival in a significant number of patients. Intracranial invasion and/or cranial nerve palsy and re-treatment dose affect the prognosis, with a dose of >/=50 Gy significantly improving survival. Radiosurgery boost may also improve survival. Our preliminary data indicates that conformal radiotherapy may decrease the severity of radiation-induced complications. However; longer follow-up and larger sample size is necessary to document the findings.

The versatile anterolateral thigh flap: a musculocutaneous flap in disguise in head and neck reconstruction

In search of an alternative soft tissue free flap donor site to radial forearm flap and rectus abdominis flap in head and neck reconstruction, we used the anterolateral thigh flap for reconstruction of various defects in the head and neck in 59 patients. The aim was to demonstrate the versatility of this donor site and propose a new approach to achieve a safer flap dissection. With the exception of three cases, all defects resulted from excision of malignant tumours. The defects were categorised as full thickness defects of the mandible (33.9%), full thickness defects of the cheek (52.5%) and others (13.6%). During the flap dissection a direct septocutaneous pedicle was observed in 12% of the cases. In the remaining cases there were only musculocutaneous perforators and the flaps were raised either as a split vastus lateralis musculocutaneous flap (72%) or as a perforator flap (16%), depending on the required thickness. Total flap survival was 96.7% with one total and one partial failure and two re-explorations (3.3%). The mean follow-up time was 7.1 months (range: 1-12 months). In conclusion, the anterolateral thigh flap is a versatile and dependable flap that can be adapted to any type of defect by modifying the flap design and composition. It should be considered to be a musculocutaneous flap of the vastus lateralis muscle that can also be raised as a perforator flap. When harvested and used in this context, the flap dissection becomes very safe and consistent, nullifying the only major disadvantage associated with this donor site.

Radiation-induced hearing impairment in patients treated for malignant parotid tumor

Radiation-induced hearing loss was evaluated in 21 patients with unilateral malignant parotid tumors treated with surgery and radiotherapy. The contralateral ear was used as a control. Eight patients (38%) were found to have a reduction in static compliance of the tympanic membrane (type B tympanogram) in the irradiated ear. By audiometry, significant hearing loss was found in 9 patients (43%). These hearing losses were mainly sensorineural, as shown by a similar reduction in both air and bone conduction, although mixed-type hearing loss existed in some patients. A statistically significant difference in incidence of 67% versus 0% (p = .0085) was noted for patients with a cochlear dose of greater than or equal to 60 Gy, in comparison to those receiving doses of less than 60 Gy. A type B tympanogram was also found to be a prognostic factor for significant sensorineural hearing loss. Patients with type B tympanograms had a much higher incidence of significant sensorineural hearing loss than those with type A tympanograms (88% versus 15%, p = .02). This study clearly shows that radiotherapy can induce significant hearing impairment, especially when the cochlear doses are higher than 60 Gy.

Impact of oral submucous fibrosis on chemotherapy-induced mucositis for head and neck cancer in a geographic area in which betel quid chewing is prevalent

In Southeast Asia and Taiwan, betel quid chewing is prevalent. Patients with head and neck cancer who chewed betel quid habitually seem to experience more severe chemotherapy-induced mucositis in our clinical practice. To validate this issue, patients with untreated head and neck cancer who received cisplatin (cDDP) plus a 5-fluorouracil (5-FU)-based neoadjuvant chemotherapy were included in this analysis. Information on the consumption of betel quid, tobacco, and alcohol were recorded before chemotherapy. Oral submucous fibrosis (OSF) was diagnosed clinically according to the fibrotic appearance of the mucosa and trismus. Mucositis was scored according to the World Health Organization criteria, and the mucositis score of the first course of chemotherapy was used for analysis. From December 1993 to April 1996, 120 patients were enrolled in this trial. Neither the betel quid chewing nor the cancer of the oral cavity was to be a significant factor for mucositis. However, clinically diagnosed OSF was found to display a significant correlation with more severe mucositis (p = 0.02). We concluded that in betel quid chewing-prevalent areas, OSF was a risk factor of more severe mucositis in head and neck cancer patients treated by CDDP and 5-FU-based regimens.

Oromandibular reconstruction using a third free flap in sequence in recurrent carcinoma

Successful results of a second microsurgical reconstructive attempt have been reported previously in recurrent oral carcinoma. However, the feasibility of a third free flap following a third excision has remained to be determined. Six oral carcinoma patients with multiple recurrences, surgical excisions and free flap reconstructions on three separate occasions are presented. Resections had a curative intent in all cases in the first and second ablations and in four of the six cases in the third one. Five radial forearm flaps and one double free flap were used for the first reconstruction. During the second reconstruction two radial forearm, two fibula osteoseptocutaneous, one double free flap and one rectus femoris flap were used to reconstruct the larger defects resulting from excision of the recurrent tumours. However, no vascularised bone transfers were performed following the third excision and soft tissue free flap plus plate option was used for segmental mandibular defects. There was one partial flap loss among 21 free flaps performed. Three patients died within an average of 8 months following the third reconstruction while the others remained alive, surviving an average of 6 months. In conclusion, a third free tissue transfer for reconstruction in multiply recurrent oral carcinoma was found to be feasible, safe and effective. The use of free flaps contributed to the prevention of complications in these difficult cases and enabled the patients to spend the remaining days of their lives outside hospital.

Differential and additive effects of the three conserved isoleucine residues in the promoter -10 binding region on Bacillus subtilis sigma(A) structure and function

The promoter -10 binding region of the Bacillus subtilis sigma(A) factor forms an amphiphilic alpha-helix with three conserved isoleucines located at four-residue intervals. To investigate the structural and functional roles of the three isoleucine residues, we constructed a series of sigA mutants with single and double Ile-to-Ala substitutions on the hydrophobic face of this alpha-helix and isolated intragenic revertants with either same-site or second-site suppressor that partially restores the structural stability and transcription activity of the mutant sigma(A) factors. Our data show that the three conserved isoleucine residues (Ile-194, Ile-198, and Ile-202) are involved in the hydrophobic core packing of sigma(A); they affect differentially and additively the structure and function of sigma(A), with the central isoleucine residue (Ile-198) playing the most important role. By analogy with the crystal structure of a sigma(70) peptide, it is apparent that interdigital interactions exist between the three conserved isoleucine residues and certain hydrophobic amino acids in region 2. 1 of sigma(A). They include at least the van der Waals contacts between Ile-194 and both Leu-145 and Ile-149, between Ile-198 and both Ile-149 and Tyr-153, as well as between Ile-202 and Tyr-153. The same-site suppressors, Val-194 and Val-198, restore the structural stability and transcription activity of sigma(A) by repacking the hydrophobic core of sigma(A). The second-site suppressor (S291F) appears to be allele-specific, but it is not as effective as the same-site suppressors in restoring sigma(A) structure and function.

Identification and characterization of a stress-responsive promoter in the macromolecular synthesis operon of Bacillus subtilis

Bacillus subtilis DB1005 is a temperature-sensitive (Ts) sigA mutant. Induction of sigmaA has been observed exclusively in this mutant harbouring extra copies of the plasmid-borne Ts sigA gene transcriptionally controlled by the P1P2 promoters of the B. subtilis macromolecular synthesis (MMS; rpoD or sigA) operon. Investigation of the mechanisms leading to the induction has allowed us to identify a sigmaB-type promoter, P7, in the MMS operon for the first time. Therefore, at least seven promoters in total are responsible for the regulation of the B. subtilis MMS operon, including the four known sigmaA- and sigmaH-type promoters, as well as two incompletely defined promoters. The P7 promoter was activated in B. subtilis after the imposition of heat, ethanol and salt stresses, indicating that the MMS operon of B. subtilis is subjected to the control of general stress. The significant heat induction of P7 in B. subtilis DB1005 harbouring a plasmid-borne Ts sigA gene can be explained by a model of competition between sigmaA and sigmaB for core binding; very probably, the sigmaB factor binds more efficiently to core RNA polymerase under heat shock. This mechanism may provide a means for the expression of the B. subtilis MMS operon when sigmaA becomes defective in core binding.

Management of secondary soft-tissue deficits following microsurgical head and neck reconstruction by means of another free flap

Secondary soft-tissue deficits may develop following a microsurgical reconstruction in the head and neck region because of inadequate planning or chronic effects of radiotherapy. Although most cases could be managed with alternative methods, free flaps might be necessary in difficult cases. Herein are described 11 cases of microsurgical head and neck reconstruction in which secondary soft-tissue deficits required transfer of another soft-tissue free flap. All patients had malignant tumors treated with surgical resection, and their defects were reconstructed with free flaps. Seven patients received either preoperative or postoperative adjunctive radiotherapy. These patients gradually developed signs and symptoms of soft-tissue deficiency in the reconstructed area, and a soft-tissue free flap transfer was required for treatment within an average of 21.5 months of their initial reconstruction. Five rectus abdominis, one rectus femoris, one latissimus dorsi, one tensor fasciae latae myocutaneous, one radial forearm, one medial arm, and one dorsalis pedis flap were used for this purpose. All flaps survived completely. The average follow-up time was 32 months. Significant improvement was achieved in all cases, and no further major surgical procedures were required. Secondary soft-tissue deficits that could not be predicted or prevented during the initial microsurgical reconstruction may be treated successfully by a subsequent free soft-tissue transfer in selected cases.

Gastric adenocarcinoma with tonsil and submaxillary gland metastases: case report

Local invasion, hematogenous and lymphatic metastases are the major modes of spreading gastric cancer. The most common sites of metastases in patients with gastric cancer are liver, peritoneum, omentum, lungs and mesentery. Of the two pathological types of gastric cancer, intestinal-type gastric cancer showed preferential metastasis to the liver, whereas the diffuse-type showed a preference for peritoneal involvement and lymph node metastasis. However, metastases of gastric cancer to the head and neck regions are not common. The hematogenous route appears to account for a great majority of metastases to the head and neck regions. Malignant neoplasm metastases to major salivary glands or tonsils are not common. Several patients with cancers from the infraclavicular area have been reported with parotid gland or tonsil metastases. However, metastasis of gastric adenocarcinoma to the tonsils or submandibular glands is rare. We present a patient with recurrent gastric adenocarcinoma with both tonsil and submandibular gland metastases which is even rarer.

Hypopharyngeal carcinoma with clinical peritoneal carcinomatosis: a report of two patients

Most patients with hypopharyngeal carcinomas show advanced disease, either at the primary site or in the neck, at the time of diagnosis. Despite intensive therapy, a great number of recurrences and distant metastases can be observed. The most common metastatic sites are the lung and bone, and only in autopsy cases has peritoneum carcinomatosis been mentioned as a metastatic site. Since January 1992, two of 78 patients (2.3%) with advanced hypopharyngeal squamous cell carcinomas (SCCs) treated initially by chemotherapy in our department developed clinical peritoneal carcinomatosis during their natural courses. Both patients were man patients with advanced locoregional disease at stage T4N3. Their clinical peritoneal carcinomatosis appeared during chemotherapy, with good disease control above the clavicle. Both patients eventually died of sepsis within 1 month after diagnosis of the peritoneal carcinomatosis. The authors suggest that peritoneal carcinomatosis is not as rare as previously believed, and should be included in the differential diagnosis in patients with advanced hypopharyngeal SCC with abdominal symptoms. Peritoneal carcinomatosis appears to be refractory to chemotherapy, and carried a poor prognosis in patients in the present study.

Early stage nasopharyngeal carcinoma: radiotherapy dose and time factors in tumor control

OBJECTIVE

To evaluate radiotherapy dose and length of treatment in the control of early stage nasopharyngeal carcinoma (NPC) treated with a combination of external radiotherapy and brachytherapy,

MATERIALS & METHODS

We reviewed the records of 133 patients with early stage nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who received definitive radiotherapy in Chang Gung Memorial Hospital from 1979 to 1991. The median follow-up time was 7.1 years with a minimum of 2 years. All patients were treated with megavoltage external radiotherapy to the nasopharynx area (63-72 Gy) followed by high dose rate intracavitary brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4 Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used to examine the effect of several variables on prognosis.

RESULTS

The 5-year rates were 86.4% for local control, 84.7% for disease free survival, 88.5% for actuarial survival and 84.2% for overall survival. The treatment group (combination of time and dose of irradiation) was the most important prognostic factor according to Cox's proportional hazard model. Patients receiving radiation at a total dose of < or = 75 Gy completed in < 12 weeks showed the best prognosis.

CONCLUSION

Treatment time and total treatment dose are both important factors in treating early stage NPC. Decreasing the total radiation time to < 12 weeks and not exceeding a radiation dose of 75 Gy gave the best results.

Bilateral multicystic kidney dysplasia in a fetus with neonatal pulmonary hyaline membrane disease: a case report

Multicystic kidney disease is the most common cause of neonatal renal mass and either the most or second most common neonatal abdominal mass. This disease is a congenital dysplasia of the kidney characterized by large nonhomogeneous dilations of the collecting tubules. It may occur unilaterally or bilaterally, and the incidence is about 1 out of 5,000 to 10,000 births. Severe bilateral defects are lethal. Partial dysplastic involvement of both kidneys eventually leads to renal function impairment. This is a case of bilateral multicystic kidney dysplasia diagnosed prenatally at 34 weeks of gestation. Hyaline membrane disease was found in both lungs after delivery. The antenatal diagnostic criteria for multicystic kidney disease and treatment after diagnosis are also discussed.

The importance of a proper helical structure in the promoter-10 binding region to Bacillus subtilis sigma A structure and function

Two Bacillus subtilis sigA mutants with amino acid substitutions tending to disrupt the structure of the promoter -10 binding helix of B. subtilis sigma A factor were constructed. B. subtilis DB1001 which contained an A197P substitution was very sensitive to temperature elevation. B. subtilis DB1002 had a T199G substitution and was low in growth potential at the elevated temperature. Degradation of sigma A in B. subtilis DB1001 (t(1/2)=63.2 min) and DB1002 (t(1/2)=186.0 min) occurred readily even at 37 degrees C; however, sigma A in B. subtilis DB2 (wild-type) was fairly stable at the same temperature. The activities of both DB1001 and DB1002 sigma A factors on groE promoter (sigma A-type) were lower than those of the wild-type counterpart at both permissive and restrictive temperatures. The failure of a higher sigma A concentration to suppress the Ts phenotype of DB1001 indicated that the temperature sensitivity of B. subtilis DB1001 was due to altered function, rather than insufficient concentration, of sigma A in the cells. Taken together, our results suggest that the helicity of the promoter -10 binding helix is essential to the packing interaction in the hydrophobic core region of sigma A, which helps to maintain the stable and functional sigma A structure.

Acute toxicities and feasibility of altered fractionated radiotherapy in nasopharyngeal carcinoma

BACKGROUND

Altered fractionated radiotherapy (AFR) has been used for many years in the treatment of cancer. Although AFR therapy improves tumor control, it also increases acute radiation toxicities, which may make patients withdraw from treatment. Here, we report on the efficacy of AFR in the treatment of nasopharyngeal cancer (NPC).

METHODS

From September 1993 to October 1994, 68 NPC patients received AFR in Chang Gung Memorial Hospital-Linkou. The efficacy of two types of AFR were studied: (a) Hyperfractionated radiotherapy (HFT) in which irradiation was given twice a day throughout the radiotherapy course with a total radiation dose of 81.6 Gy/68 fractions in 7 weeks; and (b) Concomitant boost radiotherapy (CBT) in which additional concommitant radiotherapy was administered only during the last 2 weeks of the radiotherapy course. The total radiation dose of CBT was 72.3 Gy/42 fractions in 6 weeks. Twenty-six patients received HFT and 42 received CBT.

RESULTS

The percentage of grade 3 complications was 73% in CBT and 65% in HFT. The mean number of treatment days was 57.1 in HFT (median, 53; range 48-63) and 43.9 in CBT (median, 43; range 40-60). No patient withdrew from or prolonged the treatment because of acute radiation toxicities.

CONCLUSION

Our results demonstrated that NPC patients can tolerate HFT and CBT radiotherapy with sufficient psychological support. Further randomized trials will be continued in our institution.

The response of a Bacillus subtilis temperature-sensitive sigA mutant to heat stress

The mutant sigA allele of Bacillus subtilis DB1005 was confirmed to be temperature sensitive (ts) and transferable among strains of B. subtilis by chromosomal transformation and gene conversion. This ts sigA allele had a pleiotropic effect on gene expression of DB1005. The induction of certain heat shock proteins in DB1005 was markedly less significant than that observed in the wild-type strain (DB2) under heat stress. In contrast, some proteins required for coping with oxidative stress and glucose starvation were induced abruptly in DB1005 but not in DB2. Heat induction of the groEL gene in vivo at both transcription and translation levels was much lower in DB1005 than in DB2. Besides, the putative sigma A-type promoter from the groESL operon of B. subtilis was able to be transcribed by the reconstituted sigma A RNA polymerase in vitro at both 37 and 49 degrees C. These results strongly suggest that the expression of the groEL gene of B. subtilis under heat stress is regulated at least in part by sigma A at the level of transcription. Our results also showed that DB1005 did not respond too differently from the wild type to ethanol stress, except after a relatively long exposure.

Comparison of radiotherapy and surgical results of early stage glottic cancer: a retrospective analysis

From March 1977 to October 1989, 85 patients with early stage glottic cancer were treated with either radiotherapy or surgery at Chang Gung Memorial Hospital (CGMH). Patients were excluded from the analysis of local control if they died or remained disease-free with a follow-up period of less than two years. Of the 26 patients treated with definitive radiotherapy, initial control of the primary lesions was achieved in 100% of stage T1s, 76% of T1, and 57% of T2 patients. Surgical salvage of radiation failure was achieved in 83% of the patients, giving the ultimate local control of 100% for T1s, 94% for T1, 86% for T2 patients. Of the 44 patients treated with definitive surgery, initial control of the primary lesions was achieved in 100% for T1s, 95% for T1, and 78% for T2 patients. Salvage of the surgical failure was 50%, giving the ultimate control in this group of 100% for T1s, 95% for T1, 83% for T2. There was no difference in either initial or ultimate control of T1 and T2 lesions between patients treated with primary radiotherapy and primary surgery. Voice preservation rates were 73% and 34% in the radiotherapy and surgery group, respectively. When divided into two groups according to the times they were being treated, we found that surgery preserved a comparable number of larynges as radiotherapy did after 1988 (60% vs 77%, p = 0.33). It is concluded that radiotherapy and surgery could achieve the same good local control results and long-term survival and comparable functional results of early stage glottic cancer, if conservative surgery is carefully selected for each patient.(ABSTRACT TRUNCATED AT 250 WORDS)