Arterial blood gas analysis predicts futile recanalization in mechanical thrombectomy-treated acute ischemic stroke patients: a multicenter study

OBJECTIVE: It is known that providing recanalization alone in large vessel occlusions is not sufficient to provide a good 90-day clinical outcome. It is advocated that neuroprotection should be increased before endovascular treatment and that the penumbra should be protected from reperfusion damage after recanalization. However, the effects of blood gas parameters before and after mechanical thrombectomy on clinical outcomes are not clear. The objective of this study is to assess the effectiveness of serial blood gas measures in accurately predicting futile recanalization at an early stage. PATIENTS AND METHODS: This study is a multicenter inquiry that collected data in a prospective manner and analyzed it retrospectively. Patients with a 2b-3 thrombolysis in cerebral infarction (TICI) score after mechanical thrombectomy for recanalization were consecutively analyzed from July 2022 to March 2023. Arterial blood gas parameters, including pH, oxygen saturation (SaO2), partial carbon dioxide pressure (PaCO2), partial oxygen pressure (PaO2), lactate, and bicarbonate (HCO3), were measured at four time points: before mechanical thrombectomy treatment (preoperative), immediately after recanalization (postoperative 1st), during the 3rd hour (postoperative 3rd), and at the 5th hour (postoperative 5th). The patients were categorized into groups based on their modified Rankin Scale (mRS) scores. RESULTS: The study included 136 patients with an average age of 69.71±11.22. The postoperative 1st-hour SaO2 values were lower in the mRS 3-6 group (p=0.038). The postoperative pH and lactate mean were greater in the mRS 3-6 group than in the 0-2 group (p=0.038 and 0.018, respectively). In logistic regression, a unit rise in lactate increased poor functional outcomes 1,632 times (p=0.024). Early neurological recovery was associated with decreased postoperative 3rd-hour lactate (p=0.014). The mean postoperative PaO2 (average of 1, 2, 3 PaO2) was higher in those with symptomatic cerebral bleeding (p=0.044). CONCLUSIONS: Monitoring lactate and pH levels in AIS patients who have had mechanical recanalization can be utilized to predict mortality and morbidity, especially in the first five hours after the procedure.

Graphical Abstract

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Clinical validation of SARC-F by proxy as a practical tool to evaluate sarcopenia in dependent older adults

INTRODUCTION

Sarcopenia is a prevalent disorder in older adults with significant adverse outcomes and regular screening is recommended for those at risk. The SARC-F questionnaire is the most commonly recommended screening tool for sarcopenia. However, as a self-reported tool, it cannot be applied to dependent individuals with communication problems. We hypothesized that implementation of the proxy-reported SARC-F (SARC-F by proxy) would be non-inferior in screening sarcopenia when compared with the standard SARC-F. Thus, we aimed to investigate the clinical validity of the SARC-F by proxy in identifying sarcopenia in older adults and to compare its performance with the standard SARC-F. Additionally, we aimed to determine the ideal cut-off of SARC-F by proxy in screening sarcopenia.

MATERIALS AND METHODS

This is a validation study including older adults aged ≥60 years without communication problems and their close proxies. The participants were recruited from a geriatric outpatient clinic of a tertiary health center and a nursing home. Standard SARC-F was transformed to SARC-F by proxy and administered to the proxies of older adults, and standard SARC-F was administered to the patients simultaneously in different rooms. We defined sarcopenia as probable and confirmed by the EWGSOP2 consensus report. We performed receiver operating characteristics (ROC) and sensitivity/specificity analyses of SARC-F by proxy for diagnosing sarcopenia and compared its performance with standard SARC-F by the DeLong test.

RESULTS

We included 172 older adults (median age: 72; 44.8% female) and 107 proxies in close contact (median age: 55, 63.2% female). The prevalence of probable and confirmed sarcopenia was 18.9% and 12.9%, respectively. For both definitions, area under the curve (AUC) values of SARC-F by proxy and standard SARC-F were moderate and similar [probable sarcopenia: 0.619 and 0.624 (p = 0.9); confirmed sarcopenia 0.613 and 0.645 (p = 0.7), respectively]. The best balance between sensitivity and specificity was achieved with a SARC-F by proxy score of ≥2 for both sarcopenia definitions (sensitivity levels were 74.7% and 77.8%, and specificity levels were 50.0% and 49.6%, for probable and confirmed sarcopenia, respectively).

DISCUSSION

SARC-F by proxy showed a similar, non-inferior performance compared to the standard SARC-F in the evaluation of sarcopenia. Our results suggest that it can be used instead of standard SARC-F to screen sarcopenia in older patients with communication problems. Further validation studies in different populations are warranted to support our findings.

Associations between obesity, self-reported weakness and their combinations with mortality in nursing home residents

OBJECTIVES

There are studies on associations between obesity and mortality in nursing home (NH) residents, but the presence of concomitant muscle weakness has not been examined. We considered that self-reported weakness might be a low muscle strength proxy marker. We aimed to examine associations of obesity alone, self-reported muscle weakness alone, and their combination with mortality in NH residents.

METHODS

This is a retrospective longitudinal follow-up study. We noted age, sex, nutritional status, functionality, number of chronic diseases, and regular medication. Obesity was assessed by the body fat-percentage method estimated by bioimpedance analysis. Weakness was identified by self-reported muscle weakness. Survival was evaluated with a univariate log-rank test and multivariate Cox regression analyses.

RESULTS

We included 214 participants. In a median follow-up time of 46 months, mortality occurred in 37.4%. In multivariate analysis adjusted by age, sex, undernutrition, number of chronic diseases, and regular medication, functional scores; 'non-weak non-obese' participants or 'weak alone' participants or 'weak+obese' participants had higher mortality risk when compared with the 'obesity alone' participants [hazard ratio (HR) = 2.6, 95% confidence interval (CI) = 1.2-5.5, p = 0.01; HR = 2.6, 95% CI = 1.2-5.9, p = 0.02; HR = 3.0, 95% CI = 1.2-7.7, p = 0.02].

CONCLUSION

This is the first report showing that obesity was associated with lower mortality risk if the weakness was not present in NH residents. However, obesity with concomitant weakness was associated with mortality risk similar to non-weak non-obese or weak alone participants. Our study suggests a simple consideration of weakness that can easily be integrated into everyday practice.

Urinary trehalase activitiy in contrast-associated acute kidney injury

OBJECTIVE

Contrast-associated acute kidney injury (CA-AKI) is the third most common cause of hospital-acquired AKI. Sensitive biomarkers can detect kidney injury early on because kidney damage begins immediately after the administration of a contrast medium. Due to its proximal tubule specificity, urinary trehalase can be a useful and early marker for detecting tubular damage. This study aimed to reveal the power of urinary trehalase activity in diagnosing CA-AKI.

PATIENTS AND METHODS

This is a prospective, observational, and diagnostic validity study. The study was performed in an academic research hospital's emergency department. Patients aged 18 years and over who underwent contrast-enhanced computed tomography in the emergency department were included in the study. Urinary trehalase activities were measured before and 12, 24, and 48 hours after the administration of a contrast medium. The primary outcome was the occurrence of CA-AKI, while the secondary outcomes were risk factors for CA-AKI, duration of hospital stay after contrast use, and the mortality rate in the hospital.

RESULTS

A statistically significant difference between the CA-AKI group and the non-AKI group was found in the activities measured 12 hours after the administration of the contrast medium. Notably, the mean age of the patient group with CA-AKI was considerably higher than that of the non-AKI group. The risk of mortality was found to be remarkably more elevated in patients with CA-AKI. Further, there was a positive correlation between trehalase activity and HbA1c. In addition, a crucial correlation was found between trehalase activity and poor glycemic control.

CONCLUSIONS

Urinary trehalase activity can be useful as a marker of acute kidney injuries due to proximal tubule damage. In the diagnosis of CA-AKI, especially the activity of trehalase in the 12th hour might be useful.

OS12.7.A Characterization of intra-tumoral heterogeneity and differential immune activation during malignant progression of meningiomas on single cell level

BACKGROUND

As the most common intracranial tumor, meningiomas have caused increasing interest in the field of medical research. Based on their mutational profile, meningiomas can be separated into two main groups: NF2 altered meningiomas, which can occur at WHO grades 1 to 3, and non-NF2 mutant meningiomas with mutations in other genes, such as TRAF7, AKT1, KLF4, and SMO, which are usually of WHO grade 1. While this means that non-NF2 mutant meningiomas usually follow a benign course, risk stratification for NF2 mutant meningiomas remains difficult. As of now, the underlying mechanisms contributing to the malignant phenotype of some NF2 mutant meningiomas remained unknown, even though some molecular markers have been associated with an increased risk of recurrence. Here, we sought to characterize robust molecular subgroups for meningiomas and identify the critical steps in malignant progression of these tumors.

MATERIAL AND METHODS

We applied bulk RNA sequencing and proteomic analyses for 44 meningioma samples as well as single nuclei RNA sequencing analyses for an additional set of 26 meningiomas with a total of 46,002 nuclei. Both datasets comprised samples across the molecular landscape of meningiomas and WHO grades 1, 2, and 3.

RESULTS

The meningioma subgroups previously identified on epigenomic level were found consistently also on transcriptomic, proteomic, and phospho-proteomic levels. In addition, strong differences in numbers and types of infiltrating immune cells between subgroups became apparent. A decreased number of infiltrating macrophages and an activation to a more proinflammatory phenotype was observed for WHO grade 3 tumors. This observation correlated with lower expression levels of CSF1 in tumor cells of WHO grade 3 meningiomas, which was predicted to stimulate macrophages in WHO grade 1 and 2 tumors. Moreover, we identified several tumor cell subpopulations, each defined by a distinct phenotype, shared across samples. Their proportions in the tumor strongly depended on tumor grade. Especially a subpopulation characterized by an elevated stress response and TGFβ signaling activity was found specifically in WHO grade 3 cases.

CONCLUSION

Our findings establish molecular subgroups for meningiomas that are robust across multiple levels with characteristic differences in pathway activities and demonstrate a subtype-specific immune activation, both of which may be basis for novel treatment strategies.

P07.04 Rapid-CNS2: Rapid comprehensive adaptive nanopore-sequencing of CNS tumors, a proof of concept study

BACKGROUND

The WHO classification 2021 includes multiple molecular markers for routine diagnostics in addition to histology. Sequencing setup for complete molecular profiling requires considerable investment, while batching samples for sequencing and methylation profiling can delay turnaround time. We introduce RAPID-CNS2, a nanopore adaptive sequencing pipeline that enables comprehensive mutational, methylation and copy number profiling of CNS tumours with a single third generation sequencing assay. It can be run for single samples and offers highly flexible target selection requiring no additional library preparation.

MATERIAL AND METHODS

Utilising ReadFish, a toolkit enabling targeted nanopore sequencing, we sequenced DNA from 22 diffuse glioma patient samples on a MinION device. Target regions comprised our Heidelberg brain tumour NGS panel and pre-selected CpG sites for methylation classification by an adapted random forest classifier. Pathognomonic alterations, copy number profiles, and methylation classes were called using a custom bioinformatics pipeline. Results were compared to their corresponding NGS panel-seq and EPIC array outputs.

RESULTS

Complete concordance with the EPIC array was found for copy number profiles from RAPID-CNS2. 94% pathognomonic mutations were congruent with NGS panel-seq. MGMT promoter status was correctly identified in all samples. Methylation families were detected with 96% congruence. Among the alterations decisive for rendering a classification-compatible integrated diagnosis, 97% of the alterations were consistent over the entire cohort (completely congruent in 19/22 cases and sufficient for unequivocal diagnosis in all).

CONCLUSION

RAPID-CNS2 provides a swift and highly flexible alternative to conventional NGS and array-based methods for SNV/Indel analysis, detection of copy number alterations and methylation classification. The turnaround time of ~4 days can be further shortened to <12h by altering target sizes. It offers a low-capital approach that would be cost-efficient for low throughput settings and invaluable in cases requiring immediate diagnoses.

Success of Simpler Modified Fried Frailty Scale to Predict Mortality among Nursing Home Residents

OBJECTIVE

Fried frailty scale is the very first and most commonly used assessment scale for an operational definition of frailty with its demonstrated success as a predictor of mobility limitations and mortality. However, it is impractical for use in routine clinical practice. We aimed to study whether a simpler modified Fried frailty scale could predict mortality among nursing home residents.

DESIGN

Retrospective longitudinal follow-up study.

SETTING

Nursing home. Baseline evaluation was performed in 2009. Mortality was assessed after 4 year.

PARTICIPANTS

Two hundred-twenty-four participants were included.

MEASUREMENTS

Residents were assessed for demographic characteristics, falls, dementia, the number of regular medications and chronic diseases, body composition by bioimpedance analysis, basic and instrumental activities of daily living besides frailty status by a modified Fried frailty scale. The residents were assessed for mortality after a median follow-up time of 46 months. The association of frailty with mortality was analyzed by the Kaplan-Meier Log-rank test and multivariate Cox Regression analysis.

RESULTS

Mortality occurred in 90 (40.2%) of the residents. In multivariate analysis, frailty was an independent predictor of death (Hazzard ratio= 1.4, 95% confidence interval= 1.03-2.6, p=0.03) when adjusted by age, sex, presence of malnutrition, low muscle mass, number of chronic diseases and regular medications.

CONCLUSION

Our results suggest that the simpler modified Fried frailty scale can be used as a screening tool for frailty in everyday practice as a tool to identify risky patients for mortality. Future reports studying its role in predicting other adverse outcomes associated with frailty are needed.

Effect of melatonin on torsion and reperfusion induced pathogenesis of rat uterus

We investigated the use of melatonin to improve fertility and reduce uterine damage caused by torsion of the uterus in pregnant rats. We used 35 pregnant rats at gestational age 18 days. The animals were randomized into five groups. Group 1 was anesthetized only. Group 2 was subjected to experimental uterine torsion of 360° and the torsion was corrected after 6 h. Group 3 was subjected to uterine torsion of 360°, the torsion was corrected after 6 h and melatonin was administered at the time of correction. Group 4 rats were subjected to 360º uterine torsion and melatonin was administered 6 h later at the time of correction. Group 5 was administered melatonin followed by uterine torsion of 360 degrees followed by correction of torsion 6 h later. Samples were obtained from the uterine horns on the day 1 postpartum. We used Bax, Bcl-2 and caspase 3 staining to measure apoptosis in the uterine tissues. The mRNA levels of Rho-associated, coiled-coil containing protein kinases 1 (ROCK1), homeobox D10 (Hox4 HoxD10), TLR4, NFκB1, caveolin 1 (Cav1) heat shock protein 90 alpha (cytosolic), class B member 1 (Hsp90ab1) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were determined using quantitative real-time polymerase chain reaction analysis (qRT-PCR). Bax, Bcl-2 and caspase 3 were detected using immunohistochemistry. No difference was observed among groups with respect to abortion, neonatal mortality or congenital abnormalities. Compared to the control group, the mRNA levels of Rock1, Hox4, TLR4, NFκB1, Cav1 and Hsp90 genes were decreased significantly in the study groups; the decrease was greater in groups 3 and 4, which were treated with melatonin. The greatest amount of Bax staining was found in group 1 and the least amount of Bcl-2 staining was found in groups 4 and 5; the greatest amount of caspase 3 staining was found in group 2. Our findings indicate that melatonin reduced uterine torsion related tissue damage and that its application during torsion was more effective than application following removal of torsion.

Modelling acoustic scattering, sound speed, and attenuation in gassy soft marine sediments

A model for nonlinear gas bubble pulsation in marine sediments is presented. This model is then linearized to determine the resonance frequency and the damping terms for linear radial oscillations. The linear model is then used to predict the effects that such bubble pulsations will have on the sound speed and attenuation of acoustic waves propagating in gassy marine sediment. The results are compared for monodisperse populations against the predictions of a model of Anderson and Hampton and, furthermore, the additional abilities of the model introduced in this paper are discussed. These features include the removal of the sign ambiguities in the expressions, the straightforward implementation for acoustic propagation through polydisperse bubble populations, the capability to estimate bubble size distributions through a full acoustic inversion, and the capability to predict nonlinear effects.

Changes in Exfoliative Cell of Oral Mucosa in Kidney Transplant Patients

OBJECTIVES

The aim of this study was to investigate quantitative cytologic changes in oral mucosal smears collected from kidney transplant patients by modern stereologic methods.

METHODS

We enrolled 32 kidney transplant patients. Smears were obtained from the buccal mucosa transplant patients before and 12 months after kidney transplantation. Smears from each individual were stained using the Papanicolaou method and were analyzed using a stereological method.

RESULTS

Statistically, the nuclear volumes and cytoplasmic volumes in the cells of buccal mucosa were markedly higher after kidney transplantation (P < .05). There was a decreased positive cell density in the oral epithelial cells after kidney transplantation compared with before renal transplantation (P < .05).

CONCLUSIONS

These findings suggest that there are alterations in the oral epithelial cells after kidney transplantation, which are detectable by microscopy and cytomorphometry.

Human papillomavirus effect on the development of endometrial polyps

AIM

Although the association of human papillomavirus (HPV) with warts arising in different parts of the human body has been well-demonstrated, the association of HPV with endometrial polyps has never been studied in the literature up to now.

MATERIALS AND METHODS

Detection of the HPV DNA was carried out by using 13 high-risk HPV real-time PCR Kit and five low-risk HPV real-time PCR Kit.

RESULTS

Among 50 endometrial polyp samples, one endometrial polyp sample revealed a positive result for the presence of HPV type 18.

CONCLUSIONS

This first study in the medical literature investigating the possible effect of HPV on the development of endometrial polyps has demonstrated that HPV might have a role in the development of some of the endometrial polyps. If the present authors' hypothesis that endometrial polyps caused by carcinogenic HPV types are prone to proceed to endometrial cancer if left untreated is correct, HPV vaccine has a potential to prevent development of at least some of the endometrial polyps and endometrial cancers.

The association between inherited thrombophilia and recurrent pregnancy loss in Turkish women

OBJECTIVE

To investigate the relation between recurrent pregnancy loss (RPL) and factor V Leiden, prothrombin G20210A, and C677T methylenetetrahydrofolate reductase (MTHFR) mutations.

MATERIALS AND METHODS

A case-control study was conducted on 95 consecutive cases with RPL, and 40 age-matched controls who had no history of pregnancy loss and had at least one successful pregnancy. After application of exclusion criteria, 60 patients in the study group and 40 control cases were compared for thrombophilic factors.

RESULTS

Thirteen out of 60 RPL cases and one out of 40 in the control group were carriers of factor V Leiden mutation. While six patients were carriers of prothrombin G20210A gene mutation, none in the control group carried this mutation. Twenty-nine out of 60 RPL cases and 17 out of 40 control cases had MTHFR mutation.

CONCLUSION

The authors found a positive correlation between RPL and FVL and FII gene mutations, but no significant association between RPL and MTHFR gene mutation.

Fibroblast growth stimulation by extracts and compounds of Onosma argentatum roots

The roots of Onosma argentatum are used traditionally in Turkey for wound healing and burns. The n-hexane-dichloromethane extract of the roots, and four shikonin derivatives (deoxyshikonin, acetyl shikonin, 3-hydroxy-isovaleryl shikonin and 5,8-O-dimethyl acetyl shikonin) isolated from the n-hexane-dichloromethane extract were investigated for their ability to stimulate the growth of human amnion fibroblasts. A range of concentrations was studied and the extract found to stimulate the growth of human amnion fibroblasts in vitro at 0.1 microg/mL whilst 5,8-O-dimethyl acetyl shikonin had the same effect at 0.05-5 microg/mL, although cytotoxicity was observed at 50 microg/mL for all samples. The extract and all the other isolated compounds showed cytotoxicity at 10 microg/mL with the extract and 3-hydroxy-isovaleryl shikonin showing cytotoxicity at 5 microg/mL. It is suggested that any wound healing effect of the roots of Onosma argentatum might be partly due to an additive effect of the shikonin derivatives present.

Effects of eight weeks of exercise training and orlistat therapy on body composition and maximal exercise capacity in obese females

A comparative assessment was made of the short-term effects of orlistat therapy and exercise training on body composition and aerobic fitness in obese females. A total of 24 obese patients were enrolled in to the study; 12 received orlistat therapy (DO) and 12 participated in a regular aerobic exercise-training programme (DE). All patients were on hypocaloric diets. Each patient performed three incremental ramp exercise tests (one at Week 0, one at the end of Week 4 and one at the end of Week 8) to exhaustion using an electromagnetically braked cycle ergometer to determine their anaerobic threshold and maximal exercise (Wmax) capacity. Patients in the DE group performed continuous exercise at a work rate that corresponded to the anaerobic threshold. Weight loss and loss of fat mass after 8 weeks were -6.4% (P=0.002) and -13.4% (DE) vs -5.8% (P=0.002) and -6.4% (P=0.008) (DO), respectively. Wmax capacity was 90.8+/-5 W (basal) vs 92.9+/-5 W (Week 4, P=0.1) and 100.4+/-6 W (Week 8, 10.5%, P=0.04) in the DO group, and 96.2+/-6 W (basal) vs 129.1+/-4 W (Week 4, 34.1%, P=0.002) and 137.5+/-5 W(Week 8, 42.9%, P=0.002) in the DE group. Despite similar decreases in body weight in both groups, patients in the DE group achieved a markedly higher level of Wmax, reflecting a better improvement in cardiopulmonary fitness, compared with patients in the DO group. Considering the improvement of aerobic fitness in the short term, an aerobic exercise-training programme should be considered for sedentary obese patients to improve their aerobic fitness and thereby reduce the negative outcomes of obesity.

Intravitreal triamcinolone acetonide for treatment of persistent macular oedema in branch retinal vein occlusion

BACKGROUND

To evaluate the efficacy of intravitreal triamcinolone acetonide injection on persistent macular oedema in branch retinal vein occlusion that fails to respond to previous laser photocoagulation.

MATERIAL AND METHODS

A total of 19 eyes of 19 patients with persistent macular oedema due to branch retinal vein occlusion were treated with 8 mg/0.2 ml of intravitreal triamcinolone acetonide injection. The main outcome measures included best-corrected visual acuity, intraocular pressure, and macular oedema map values of Heidelberg Retinal Tomograph II (HRT II) before and after intravitreal triamcinolone injection.

RESULTS

The mean follow-up time was 6.2+/-1.0 months. The mean baseline best-corrected logarithm of minimal angle of resolution (LogMAR) value for visual acuities of the patients before intravitreal triamcinolone injection was 1.01+/-0.16. After treatment, it was 0.55+/-0.22 at the 1-month, 0.56+/-0.22 at 3-month, and 0.62+/-0.22 at the last visits and the differences were statistically significant when compared with baseline values (for each, P<0.001). The mean oedema map values on HRT II significantly decreased by 28.5% at 1-month, 23.8% at 3-month, and 23.8% at the last visit when compared with preinjection values (for each, P<0.001). Intraocular pressure elevation exceeding 21 mmHg was observed in 26.3% of eyes at 1-month, 15.7% at 3-month, and 5.2% at the last visit, but was controlled with topical anti-glaucomatous medications in all eyes.

CONCLUSION

Intravitreal triamcinolone acetonide application is a promising approach in the treatment of persistent macular oedema due to branch retinal vein occlusion non-respondent to laser photocoagulation.

Effects of different weight loss protocols on serum leptin levels in obese females

We investigated the effects of different weight loss protocols on leptin levels in obese females with the aim of addressing the leptin resistance which has been found to be an aggravating factor in obesity. Twenty-four obese females enrolled to one of three 12-week weight loss protocols: orlistat-induced weight loss (OWL, n=8), exercise-induced weight loss (EWL, n=8) and orlistat plus exercise-induced weight loss (OEWL, n=8). Serum leptin levels were measured in duplicate by radioimmunoassay. There were significant reductions (P<0.01) in body weight and fat mass after the 12 week period in all groups: -11.4+/-0.5 kg and -9.8+/-0.5 kg (OEWL), -8.3+/-0.8 kg and -5.7+/-0.9 kg (OWL), -8.9+/-1.2 kg and -7.4+/-1.2 kg (EWL), respectively. Serum leptin levels were also decreased markedly in all groups: -59.2 % (OEWL1), -37.8 % (OWL) and -48.6 % (EWL) (P<0.01 all). In addition, there were marked decreases in leptin levels for each kilogram of fat mass after the 12 week period: -48.2+/-7.2 % (OEWL), -27.8+/-4.8 % (OWL) and -39.3+/-4.3 % (EWL) (P<0.01 all). Decreases in serum leptin levels expressed per kilogram of fat mass were significantly higher in the OEWL group compared to the OWL group (P=0.03). Consequently, an exercise training program in adjunct to pharmacotherapy provides higher weight reduction and fat mass loss in obesity treatment. It also seems to have further beneficial effects on leptin resistance, as indicated by decreases in leptin levels expressed per kilogram of fat mass.

Effects of different weight loss protocols on serum leptin levels in obese females

We investigated the effects of different weight loss protocols on leptin levels in obese females with the aim of addressing the leptin resistance which has been found to be an aggravating factor in obesity. Twenty-four obese females enrolled to one of three 12-week weight loss protocols: orlistat-induced weight loss (OWL, n=8), exercise-induced weight loss (EWL, n=8) and orlistat plus exercise-induced weight loss (OEWL, n=8). Serum leptin levels were measured in duplicate by radioimmunoassay. There were significant reductions (P<0.01) in body weight and fat mass after the 12 week period in all groups: -11.4+/-0.5 kg and -9.8+/-0.5 kg (OEWL), -8.3+/-0.8 kg and -5.7+/-0.9 kg (OWL), -8.9+/-1.2 kg and -7.4+/-1.2 kg (EWL), respectively. Serum leptin levels were also decreased markedly in all groups: -59.2 % (OEWL1), -37.8 % (OWL) and -48.6 % (EWL) (P<0.01 all). In addition, there were marked decreases in leptin levels for each kilogram of fat mass after the 12 week period: -48.2+/-7.2 % (OEWL), -27.8+/-4.8 % (OWL) and -39.3+/-4.3 % (EWL) (P<0.01 all). Decreases in serum leptin levels expressed per kilogram of fat mass were significantly higher in the OEWL group compared to the OWL group (P=0.03). Consequently, an exercise training program in adjunct to pharmacotherapy provides higher weight reduction and fat mass loss in obesity treatment. It also seems to have further beneficial effects on leptin resistance, as indicated by decreases in leptin levels expressed per kilogram of fat mass.

Rieger anomaly with bilateral choroidal osteoma: coincidence or association?

PURPOSE

To report a case of Rieger anomaly associated with bilateral choroidal osteoma.

CASE

An 18-year-old woman presented with corectopia, iridocorneal adhesions, and stromal hypoplasia of the iris, and was diagnosed with Rieger anomaly.

RESULTS

Fundus examination revealed bilateral yellowish-orange, placoid degenerative fundus lesions with pseudopod-like edges associated with the areas of retinal pigment epithelium atrophy, indicating choroidal osteoma. Fundus fluorescein angiography showed bilateral early patchy and late diffuse hyperfluorescence. B-scan echography revealed placoid lesion at the posterior ocular coats characterized by localized areas of high ultrasound reflectivity with a corresponding retrobulbar orbital shadowing. This indicated a dense calcium foreign body. In addition, computed tomography of the orbit demonstrated bilateral plate-like thickening with calcification of the choroid that was isodense with the normal skeletal bone.

CONCLUSIONS

Although Rieger anomaly is classically known as a disease of the anterior segment of the eye, choroidal osteoma may be a posterior segment finding of the disease that has not previously been reported.

Protective effect of Copalite surface coating on mercury release from dental amalgam following treatment with carbamide peroxide

The effect of Copalite coating on mercury release from dental amalgam following treatment with 10%, 20%, 30% and 40% carbamide peroxide was assessed in vitro, using a cold-vapour atomic absorption Mercury Analyzer System. Eighty samples of dental amalgam were automatically mixed in a dental amalgamator and condensed into silicon embedding molds. Forty amalgam samples were coated with three uniform layers of Copalite intermediary varnish and the other 40 samples were left uncoated. The coated and non-coated amalgam samples were exposed for 24 h to 10%, 20%, 30% or 40% carbamide peroxide preparations and compared with samples exposed to phosphate buffer. In the non-coated samples a significant increase of mercury concentration in solution was found following exposure to all carbamide peroxide preparations tested. Mercury concentration was directly related to carbamide peroxide concentration. In the Copalite-coated samples, significantly lower concentrations of mercury in solution were found as compared to the non-coated samples (P < 0.01). In conclusion, exposure of amalgam restorations to 10%-40% carbamide peroxide-based bleaching agents increased the mercury release. Pre-coating of the external amalgam surfaces with Copalite significantly reduced the release of mercury.

The radicular groove: its potential clinical significance

This report examines three clinical cases of root-filled teeth with primary endodontic lesions. During endodontic surgery, an area of incomplete root bifurcation beginning in the coronal or middle third of the root surface and terminating at or near the apical foramen were observed. The radicular grooves of two teeth were eliminated using a round bur ("saucerization"), and the resulting defect was filled with a bone substitute or calcium sulfate and covered by an absorbable collagen membrane. The other tooth was extracted, the groove was eliminated with a similar technique, and the tooth was replanted. Bacteria have been reported in chronic apical lesions. Our observations suggest that after conventional endodontic therapy, the etiology of a nonresolving primary endodontic lesion may be bacteria of endodontic origin sequestered within the protective confines of an apical-radicular groove.

Mercury release from dental amalgam after treatment with 10% carbamide peroxide in vitro

OBJECTIVES

The effect of 10% carbamide peroxide on mercury release from dental amalgams was assessed in vitro by using a cold-vapor atomic absorption Mercury Analyzer System.

STUDY DESIGN

Samples of 4 commercial brands of dental amalgam, Megaloy (Dentsply/Caulk, Milford, Del), Mega+ (CFPM, Aulnaye, France), Nongama 2 (Silmet, Or Yehuda, Israel), and Valiant Ph.D. (Dentsply/Caulk, Milford, Del), were treated for 48 hours with 10% carbamide peroxide and compared with samples treated with phosphate buffer.

RESULTS

Amalgam specimens exposed for 48 hours to 10% carbamide peroxide showed significantly higher concentrations of mercury in solution as compared with specimens treated with phosphate buffer (P <.001). Megaloy and Valiant Ph.D. yielded significantly higher mercury concentrations in solution than Mega+ and Nongama 2 (P <.001). Mega+ yielded significantly higher mercury concentrations in solution than Nongama 2 (P <.05). No significant differences were found in mercury concentrations in solution between Megaloy and Valiant Ph.D.

CONCLUSIONS

Treatment with 10% carbamide peroxide bleaching agents caused an increase in mercury release from amalgam restorations, possibly increasing exposure of patients to its adverse effects. Amalgam brands differed in the amounts of mercury release after bleaching with carbamide peroxide.

Effect of salivary biofilm on the adherence of oral bacteria to bleached and non-bleached restorative material

OBJECTIVE

The objective of this work was to examine the effect of in vitro salivary biofilm on the adherence of oral bacteria to bleached and non-bleached restorative material (Charisma).

METHODS

Charisma samples, prepared in silicon models, were treated with either 10% carbamide peroxide (CP) or 10% hydrogen peroxide (HP). After incubation with the bleaching agent for a period of one, two or three days, the samples were coated with freshly collected human saliva. The adsorption pattern of the saliva to the restorative material was determined using gel electrophoresis coupled with computerized densitometry techniques. The amount of salivary proteins adsorbed onto the treated surfaces was measured using the Bradford method. Sucrose-dependent bacterial adhesion to the salivary-coated Charisma was tested using radio-labeled Streptococcus mutans, Streptococcus sobrinus and Actinomyces viscosus. Adhesion of each bacterium to surfaces pretreated with the bleaching agents was compared with saliva coated bleached surfaces.

RESULTS

The profile of salivary proteins adsorption followed a similar pattern in Charisma samples pretreated with either CP or HP or untreated samples. However, the total amount of salivary proteins adsorbed onto the samples decreased after bleaching with CP or HP. Salivary biofilm, coating the surface of the restorative material, significantly decreased sucrose-dependent adhesion of Streptococcus sobrinus and Streptococcus mutans to the bleached and non-bleached surfaces, compared to non-coated specimens (p < 0.05). Saliva had a minor effect on adhesion of Actinomyces viscosus.

SIGNIFICANCE

Our study demonstrates the importance of salivary biofilm in controlling adhesion of oral bacteria to restorative material pretreated with bleaching agents or untreated.

Bacterial adherence to bleached surfaces of composite resin in vitro

OBJECTIVE

The effect of bleaching agents on bacterial adherence to polished surfaces of composite resin restorations was assessed in vitro.

STUDY DESIGN

Samples of light-curing composite resins were treated with either 10% carbamide peroxide or 10% hydrogen peroxide for 1, 3, or 7 days. Bacterial adherence of Streptococcus mutans, Streptococcus sobrinus, and Actinomyces viscosus to the treated resin samples was analyzed and compared with adherence to nonbleached controls.

RESULTS

A 10% solution of carbamide peroxide caused a significant increase in surface adherence of Streptococcus mutans and Streptococcus sobrinus after 3 days (P < .01). A 10% solution of hydrogen peroxide caused a significant increase in surface adherence of Streptococcus mutans and Streptococcus sobrinus after 3 and 7 days (P < .01). A decrease in adherence of Actinomyces viscosus was found after treatment with 10% hydrogen peroxide for 7 days (P < .05).

CONCLUSIONS

It appears that bleaching agents may affect adherence of certain cariogenic microorganisms to the outer surfaces of composite resin restorations.

Measurements of axial length and radius of corneal curvature in the rabbit eye

The axial length of the eye, the radius of the anterior corneal surface, and the diameter of the cornea were measured on 40 eyes of 20 New Zealand White rabbits. The ultrasonographic measurements of the axial length of the eye showed a mean value of 15.12 +/- 0.51 mm (15.33 +/- 0.50 mm in males, 14.96 +/- 0.46 mm in females). The mean corneal radius was 7.26 +/- 0.26 mm (7.18 +/- 0.9 mm in males, 7.32 +/- 0.33 mm in females); the mean value of the difference in corneal curvature between two principle meridians was 0.21 +/- 0.12 mm; and the mean horizontal and vertical diameters of the cornea were 13.41 +/- 0.34 mm and 13.02 +/- 0.30 mm, respectively. Although the diameter of the cornea of rabbits was bigger than that of humans (average, horizontal 11.75 mm, vertical 10.55 mm), the axial length of the eye was 0.7 times that of humans (23-24 mm), and the radius of corneal curvature was relatively smaller than that in humans (7.7-7.8 mm).

The molecular mechanism of FasL-mediated cytotoxicity by CD4+ Th1 clones

Murine CD4+ Th1 clones require de novo synthesis of proteins to express a cytotoxicity that is mediated by de novo synthesized Fas ligand (FasL). The cytotoxic process of the CD4+ Th1 effectors can be separated into four stages, namely conjugate formation, activation, lethal hit, and effector-independent target cell death. The present study describes the cytotoxic process in terms of FasL induction and Fas/FasL molecular interactions for death signal transduction. Fas-Ig fusion proteins, cycloheximide, actinomycin D, and EGTA+MgCl2 were used to analyze each stage of the cytotoxic process in terms of FasL/Fas participation. The results demonstrate that the activation-induced de novo mRNA and protein synthesis were for FasL, which provided the predominant cytotoxic activity of CD4+ Th1 effectors. Once activated, Th1 effectors express cytotoxic activity in the presence of EGTA+MgCl2, an experimental [Ca2+]ext-independent condition characteristic of FasL-mediated cytotoxicity. The ability of Fas-Ig to inhibit target lysis declined rapidly after conjugate formation, indicating that FasL-mediated lethal hit is critically dependent on conjugate formation and, once delivered, the effector-independent target lysis proceeds. After the lethal hit stage, transduction of Fas-mediated death signal was independent of de novo synthesis of macro-molecules in targets because treatments that inhibited more than 98% of the macromolecule synthesis had little effect on target lysis. Our study provides the first molecular view in terms of FasL/Fas of the cytotoxic process of CD+ Th1 cells.