Predictors of in-hospital appendiceal perforation in patients with non- perforated acute appendicitis with appendicolithiasis at presentation

INTRODUCTION

Appendicolithiasis is a risk factor for perforated acute appendicitis. There is limited inpatient data on predictors of progression in appendicolithiasis-associated non-perforated acute appendicitis.

METHODS

We identified adults presenting with appendicolithiasis-associated non-perforated acute appendicitis (on computed tomography) who underwent appendectomy. Logistic regression was used to investigate predictors of in-hospital perforation (on histopathology).

RESULTS

296 patients with appendicolithiasis-associated non-perforated acute appendicitis were identified; 48 (16.2%) had perforation on histopathology. Mean (standard deviation [SD]) age was 39 (14.9) years. The mean (SD) length of stay (LOS) was 1.5 (1.8) days. LOS was significantly longer with perforated (mean [SD]: 3.0 [3.1] days) vs. non-perforated (mean [SD]: 1.2 [1.2] days) appendicitis (p < 0.001). On multivariate analysis, in-hospital perforation was associated with age > 65 years (OR 5.4, 95% CI: 1.4- 22.2; p = 0.015), BMI > 30 kg/m2 (OR 3.5, 95% CI: 1.3-8.9; p = 0.011), hyponatremia (OR 3.6, 95% CI: 1.3-9.8; p = 0.012). There was no significant association with age 25-65 years, gender, race, steroids, time-to- surgery, neutrophil percentage, or leukocyte count.

CONCLUSION

Geriatric age, obesity, and hyponatremia are associated with progression to perforation in appendicolithiasis-associated non-perforated acute appendicitis.

Urinary Morbidity in Men Treated With Stereotactic Body Radiation Therapy (SBRT) for Localized Prostate Cancer Following Transurethral Resection of the Prostate (TURP)

Background: Clinical data suggest that stereotactic body radiation therapy (SBRT) provides similar clinical outcomes as other radiation modalities for prostate cancer. However, data reporting on the safety of SBRT after TURP is limited. Herein, we report our experience using SBRT to deliver hypofractionated radiotherapy in patients with a history of TURP including physician-reported toxicities and patient-reported quality of life.

Methods: Forty-seven patients treated with SBRT from 2007 to 2016 at Georgetown University Hospital for localized prostate carcinoma with a history of prior TURP were included in this retrospective analysis. Treatment was delivered using the CyberKnife® (Accuray Incorporated, Sunnyvale, CA) with doses of 35 Gy or 36.25 Gy in 5 fractions without prostatic urethral sparing. Toxicities were recorded and scored using the CTCAE v.4. Cystoscopy findings were retrospectively reviewed. Urinary quality of life data was assessed using the International Prostate Symptom Scoring (IPSS) and Expanded Prostate Cancer Index Composite 26 (EPIC-26). A Wilcoxon signed-rank sum test was used to determine if there was a statistically significant increase or decrease in IPSS or EPIC scores between timepoints. Minimally important differences were calculated by obtaining half the standard deviation at time of start of treatment.

Results: Forty-seven patients at a median age of 72 years (range 63–84) received SBRT. The mean follow-up was 4.7 years (range 2–10 years). Late Grade 2 and grade 3 urinary toxicity occurred in 23 (48.9%) and 3 (6.4%) men, respectively. There were no Grade 4 or 5 toxicities. Approximately 51% of patients experienced hematuria following treatment. Mean time to hematuria was 10.5 months. Twenty-five cystoscopies were performed during follow-up and the most common finding was hyperemia, varices of the bladder neck/TURP defect, and/or necrotic tissue in the TURP defect. Baseline urinary QOL composite scores were low, but they did not clinically significantly decline in the first 2 years following treatment.

Conclusions: In patients with prior TURP, prostate SBRT was well-tolerated. GU toxicity rates were comparable to similar patients treated with conventionally fractionated radiation therapy. Urinary quality of life was poor at baseline, but did not worsen clinically over time. Stricter dosimetric criteria could potentially improve the rate of high-grade late toxicity, but may increase the risk of peri-urethral recurrence.

Urinary toxicity in men treated with stereotactic body radiation therapy (SBRT) for localized prostate cancer following procedures for benign prostatic hyperplasia (BPH)

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Background: Patients with a history of procedures for BPH experience worse urinary toxicity following interstitial brachytherapy for localized prostate cancer. This retrospective study sought to evaluate the rates of urinary toxicity following SBRT in men with a history of procedures for BPH. Methods: Localized prostate cancer patients, treated with SBRT from August 2009 to February 2015 and a minimum follow up of 2 years, with a history of at least 1 procedure for BPH associated with a prostatic defect identified on the treatment planning MRI were evaluated. Radiotherapy was delivered in 5 fractions to a dose of 35 or 36.25 Gy using the CyberKnife system with fiducial tracking. Urinary QOL was assessed pre- and post-treatment using the International Prostate Symptom Score (IPSS) and the Expanded Prostate Cancer Index Composite (EPIC-26). Cystoscopy findings were retrospectively reviewed. Toxicities were scored using the CTCAE v4. Results: Thirty nine men with a median age of 72 years, 7 with a history of more than 1 procedure for BPH, were treated with a median follow up of 49 months. Grade 1, grade 2, and grade 3 urinary toxicity occurred in 11, 24, and 3 men, respectively; there were no grade 4 or 5 toxicities. Overall, 22 men experienced hematuria; the median time to the onset hematuria from the start of SBRT was 13 months (range 1-70). Cystoscopy was performed on 12 of these patients and bladder neck/prostatic urethra hyperemia were found in a majority of cases. Active bleeding from the bladder neck or prostatic urethra was found in 4 men. A mean baseline IPSS score of 9 did not significantly change at any point during follow up. A mean baseline EPIC-26 obstructive/irritative score of 84 significantly decreased to 76 at 1 month (p = 0.023). There was no significant change from the mean baseline EPIC-26 urinary incontinence score at any point during follow up. Conclusions: A history of procedures for BPH may lead to worse urinary quality of life and high rates of hematuria following SBRT for localized prostate cancer. Stricter urethra/bladder neck dose constraints or an alternative fractionation schedule may be required to decrease the risk of urinary toxicity.

A novel double antibody sandwich-lateral flow immunoassay for the rapid and simple detection of hepatitis C virus

The objective of this study was to screen for antigens of the hepatitis C virus (HCV) to establish a new double antibody sandwich-lateral flow immunoassay (DAS-LFIA) method for testing the presence of anti-HCV antibodies in human serum or plasma. A series of different recombinant HCV proteins in Escherichia coli cells were constructed, expressed, purified and the new DAS-LFIA strip was developed. The sensitivity and specificity of new the DAS-LFIA strip were evaluated by detecting 23 HCV-positive sera, a set of quality control references for anti-HCV detection that contain known amounts of anti-HCV antibodies, and 8 HCV-negative sera. A total of 300 clinical serum samples was examined by both the new DAS-LFIA strip and enzyme-linked immunosorbent assay (ELISA). Data were analyzed using SPSS 11.5 software. The sensitivity and specificity of the new DAS-LFIA strip were 100%. The lowest test line of the HCV DAS-LFIA strips was 2 NCU/ml. Additionally, the concordance between the new DAS-LFIA strip and ELISA methods was 94.33%. In conclusion, our new testing method is rapid, simple, sensitive and specifically detects the presence of anti-HCV antibodies in human serum or plasma. Therefore, it may be used for monitoring HCV.

SRF binding to SRE in the rat heart: influence of age

One important promoter element at the 5' end of the c-fos gene is the serum response element (SRE). SRE is the site of attachment of the 67-kDa protein serum response factor (SRF) and several accessory proteins (Elk1, SAP1, SAP2/NET), termed the ternary complex factors. The binding of SRF to SRE plays an integral role in c-fos transcription and may occur independently of the association of the ternary complex factors. In the current study, we found that SRF protein expression was increased in the hearts of the old vs young adult rats in the basal condition. The hearts of old rats may have posttranslationally modified SRF proteins that are different compared to that of the young adults. The SRF increase was present both in the cytoplasm as well as in the nucleus in the old hearts. To test whether SRF protein levels in response to acute stress might be altered with age, we studied hearts of young adult and old rats during myocardial infarction. The young adult rat hearts responded to acute ischemic stress with an increase in both p62 and p67 SRF. The hearts of the old rats, however, did not exhibit a significant change in SRF protein expression. These findings demonstrate qualitative as well as quantitative age differences in SRF protein levels, both at baseline and following stimulation. The reduced SRF expression in response to acute cardiac ischemic stress in the old rats might contribute to the observed age-related decrease in the induction of immediate early genes such as c-fos in the heart.

Age-associated changes in basal c-fos transcription factor binding activity in rat hearts

The early response proto-oncogene c-fos is expressed at very low levels in the mammalian heart at baseline. To further investigate the mechanism of altered c-fos expression with age, we studied in the basal state the binding of five transcription proteins to their cognate sites in the c-fos promoter/enhancer region, in adult and old F344 rats. Our results show a reduced binding of E2F and AP1 proteins to the c-fos promoter in aging hearts. The major calcium/cyclic AMP response element (CRE) and SP1 binding was unchanged. The only increase seen with age was in the serum response element (SRE) binding proteins. SRE is the point of convergence of different signal transduction pathways (via MAP kinases and the Rho family of GTPases) at the c-fos promoter. Increased SRE binding may reflect a compensation for a decreased binding of other transcription proteins to the c-fos promoter, alteration in the phosphorylation status of SRF, or a change in the ternary complex factors Elk 1 or SAP 1. Other possibilities include defects in the signal transduction pathways with aging, which combine to produce an overall negative balance in the function of the c-fos promoter despite the increased SRE binding activity. Both in vitro and in vivo experiments have shown decreased c-fos expression with age. This may be due partly to alterations in the basal levels of transcription factor binding.

Biosynthesis of the antibiotic maduramicin. Origin of the carbon and oxygen atoms as well as the 13C NMR assignments

The biosynthesis of maduramicin alpha and beta in a culture of Actinomadura yumaensis has been studied using 13C, 14C and 18O labeled precursors. The alpha component of this recently discovered polyether antibiotic, containing forty-seven carbon atoms in a seven-ring system, is derived from eight acetate, seven propionate and four methionine molecules. The beta component which is missing one methoxy group incorporates three methionine methyl groups. The carbohydrate moiety was enriched by methionine, but not significantly by acetate or propionate. Studies of the incorporation of 13C labeled precursors permit the 13C NMR assignment of maduramicin. The origin of oxygen atoms of maduramicin has been examined by feeding [1-13C, 18O2]acetate and [1-13C, 18O2]propionate separately in the fermentation culture and the resulting doubly labeled maduramicin samples were analyzed by the isotopic shifts in the 13C NMR spectra. These results are consistent with the initial formation of a triene, which is converted to maduramicin by cyclization of the triepoxide.