Carcinogenicity of fibrous glass: pleural response in the rat in relation to fiber dimension

Seventeen fibrous glasses of diverse type or dimensional distribution induced different incidences of malignant mesenchymal neoplasms when implanted in the pleurae of female Osborne-Mendel rats for periods of more than 1 year. Neoplastic response correlated well with the dimensional distribution of fibers. Fibers less than or equal to 1.5 mu in diameter and greater than 8 mu in length yielded the highest probability of pleural sarcomas, and probability trends suggested that pleural sarcoma incidence increased with increasing lengths of fibers with diameters of less than 1.5 mu, Morphologic observations indicated that fibers less than or equal to 8 mu in length were inactivated by phagocytosis. In fibers greater than 8 mu in length, the correlation of carcinogenicity witth increasing length was difficult to explain. Since neoplastic response to a variety of types of durable fibers, particularly asbestos fibers, was similar, our experiments reinforce the idea that the carcinogenicity of fibers depends on dimension and durability rather than physicochemical properties and emphasize that all respirable fibers be viewed with caution.

Plasma 10-hydroxynortriptyline and ECG changes in elderly depressed patients

Among 18 elderly depressed patients given ECGs before and during nortriptyline treatment, plasma E-10-hydroxynortriptyline and the sum of E-10-hydroxynortriptyline and nortriptyline distinguished the group with conduction/repolarization effects. Plasma nortriptyline, age, drug dose, and baseline cardiovascular status did not.

Biomimetic, ROS-detonable nanoclusters - A multimodal nanoplatform for anti-restenotic therapy

The long-term success of endovascular intervention has long been overshadowed by vessel re-occlusion, also known as restenosis. Mainstream anti-restenotic devices, such as drug-eluting stent (DES) and drug-coated balloon (DCB), were recently shown with suboptimal performances and life-threatening complications, thereby underpinning the urgent need for alternative strategies with enhanced efficacy and safety profile. In our current study, we engineered a multimodal nanocluster formed by self-assembly of unimolecular nanoparticles and surface coated with platelet membrane, specifically tailored for precision drug delivery in endovascular applications. More specifically, it incorporates the combined merits of platelet membrane coating (lesion targetability and biocompatibility), reactive oxygen species (ROS)-detonable "cluster-bomb" chemistry (to trigger the large-to-small size transition at the target site, thereby achieving longer circulation time and higher tissue penetration), and sustained drug release. Using RVX-208 (an emerging anti-restenotic drug under clinical trials) as the model payload, we demonstrated the superior performances of our nanocluster over conventional poly(lactic-co-glycolic acid) (PLGA) nanoparticle. In cultured vascular smooth muscle cell (VSMC), the drug-loaded nanocluster induced effective inhibition of proliferation and protective gene expression (e.g., APOA-I) with a significantly reduced dosage of RVX-208 (1 μM). In a rat model of balloon angioplasty, intravenous injection of Cy5.5-tagged nanocluster led to greater lesion targetability, improved biodistribution, and deeper penetration into injured vessel walls featuring enriched ROS. Moreover, in contrast to either free drug solution or drug-loaded PLGA nanoparticle formulation, a single injection with the drug-loaded nanocluster (10 mg/kg of RVX-208) was sufficient to substantially mitigate restenosis. Additionally, this nanocluster also demonstrated biocompatibility according to in vitro cytotoxicity assay and in vivo histological and tissue qPCR analysis. Overall, our multimodal nanocluster offers improved targetability, tissue penetration, and ROS-responsive release over conventional nanoparticles, therefore making it a highly promising platform for development of next-generation endovascular therapies.

Leptin in postmenopausal women: influence of hormone therapy, insulin, and fat distribution

Whether use of hormone-replacement therapy (HRT) influences menopause-related changes in body weight is unclear. HRT may affect energy balance by influencing synthesis of the adipocyte-derived hormone leptin. The objectives of this study were to: 1) identify factors influencing circulating leptin in postmenopausal women; 2) determine whether HRT influences serum leptin after adjusting for confounding factors; and, 3) identify potential independent effects of HRT or leptin on resting energy expenditure (REE). Subjects were 54 postmenopausal women, 45-55 yr old, 35 of whom used HRT (estrogen plus progestin). Total and regional body composition and fat distribution were determined by dual-energy x-ray absorptiometry and computed tomography; fasting serum leptin and insulin, by RIA; and REE, by indirect calorimetry. Stepwise multiple linear regression analysis indicated that serum leptin could best be predicted from total fat mass, fasting serum insulin, and total lean mass [log leptin = 1.08 x log fat mass) + (0.46 x log insulin) + (-1.25 x log lean mass) + 1.88; model R2 = 0.78, P < 0.001]. Multiple linear regression analysis indicated that visceral fat was independently related to leptin (parameter estimate = 0.23, P < 0.05), after adjusting for s.c. abdominal fat and leg fat, as well as lean mass and insulin. After adjusting for total fat mass, total lean mass, and fasting insulin, serum leptin did not differ between users and nonusers of HRT (21.7 +/- 1.0 vs. 20.2 +/- 1.3 ng/mL, P = 0.369, adjusted mean +/- SE, respectively). Serum estradiol was inversely correlated with (adjusted) leptin in non-HRT users (r = -0.50), suggesting that ovarian senescence may lead to an increase in leptin. Multiple linear regression analysis indicated that REE (adjusted for fat mass, fat-free mass, and ethnicity) was not associated with leptin (P = 0.298) or hormone use status (P = 0.999; 1323 +/- 31 vs. 1316 +/- 42 kcal/day, adjusted mean +/- SE for users and nonusers, respectively). These results indicate that, in postmenopausal women: 1) total fat mass, lean mass, and fasting insulin, but not HRT, are significant determinants of serum leptin; 2) visceral and s.c. fat contribute to serum leptin; and, 3) neither HRT nor leptin is independently related to REE.

Postpartum patients' knowledge, risk perceptions, and behaviors pertaining to childhood injuries

The purpose of this study was to assess postpartum patients' knowledge, risk perceptions, and behaviors pertaining to a variety of childhood injuries. Although the respondents did demonstrate some knowledge of injury prevention strategies, deficits were noted in the areas of burns, motor vehicle injuries, drownings, and falls, as well as in the concept that injuries, in some children, are unavoidable. Results showed that greater than 50% of mothers did not know the temperature of their hot water tank, 22.4% who had other children under the age of four did not use car safety seats with them, and only 43% of the mothers knew how to perform infant cardiopulmonary resuscitation. Recommendations for program development in parenting classes are included in addition to the roles of nurses and nurse-midwives in injury prevention program activities.

A retrospective cohort study of the characteristics of unsuccessful operative vaginal deliveries

INTRODUCTION

Unsuccessful operative vaginal delivery (OVD) is associated with high rates of materno-fetal morbidity. We aimed to examine institutional rates of unsuccessful OVDs (uOVD) and compare them with successful OVD (sOVD) in order to identify factors to aid patient selection and education.

METHODS

A 6-month retrospective cohort study was performed on all unsuccessful and successful OVDs in a tertiary level maternity hospital in the Republic of Ireland. Maternal demographics and obstetric factors were assessed to evaluate potential underlying risk factors for unsuccessful operative vaginal delivery versus successful vaginal delivery.

RESULTS

There were 4,191 births during the study period with an OVD rate of 14.2% (n = 595) with 28 (4.7% of OVDs) being unsuccessful. Unsuccessful OVD were predominately nulliparous (25; 89.2%) with a mean maternal age of 30.1 years (range 20-42), with more than half (n = 15, 53.5%) being induced. The most common indication for induction was prolonged rupture of membranes (PROM) (n = 7, 25%) which was significantly different from the successful OVD group. A senior obstetrician was significantly more likely to be the primary operator in uOVD when compared to sOVD. (82.1 % V 54.1% p < 0.01). The majority of unsuccessful OVD were vacuum deliveries (n = 17; 60.7%), with a significantly higher mean birthweight when compared to successful OVD (3.695 kg V 3.483 kg; p < 0.01). Following an unsuccessful OVD, women were more likely to have a postpartum haemorrhage (64.2 % V 31.5% p < 0.01) and their infant was more likely to require admission to the neonatal intensive care unit (NICU) (32.1 % V 5.8% p < 0.01) when compared with successful OVD.

CONCLUSION

Risk factors for unsuccessful OVD were higher birth weight and induction of labour. There was a higher incidence of postpartum haemorrhage and NICU admission when compared with successful OVD.

Trends in operative vaginal delivery rates: A 20-year retrospective analysis in Ireland

Forceps delivery rates are increasing significantly, with a significant decrease in vacuum‐assisted delivery, with no change in neonatal morbidity or mortality.

Laser-spectroscopy testbed for impurity monitoring in liquid metal-cooled fast reactors

A significant challenge in sodium-cooled fast reactors is controlling impurities, in particular oxygen impurities, within the sodium coolant, as they can accelerate corrosion and indicate leaks. Optical methods offer the potential to rapidly detect small concentrations of both gaseous and metal impurities that accelerate corrosion, plug coolant channels, and lead to increased activation of isotopes in the coolant. We present the design and performance of an apparatus designed to enable the application of multiple optical analytical techniques, such as laser-induced breakdown spectroscopy, to detect elemental impurities in the sodium melt with high sensitivity. We experimentally demonstrate the detection of characteristic sodium and oxygen spectral lines in liquid sodium, which sets the stage for the optimization of its analytical sensitivity. A robust sensor of this type integrated with the sodium cooling loop has the potential to significantly improve the safety and operational efficiency of generation IV nuclear reactors.

The oncologist as genetic consultant: Two-year results in a large community-based practice

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Background: Oncologists are in a unique position to provide effective genetic cancer risk assessment (GCRA). However, in most communities they defer this to genetic counselors (GC). At KC Cancer Center, a 35-MD community oncology group, the difficulty obtaining timely and effective GCRA became a quality of care issue. Methods: In December 2006 a new program was launched with 4 designated oncologists providing GCRA at 4 separate cancer centers. Each oncologist was responsible for gaining expertise in the common hereditary syndromes and appropriate interpretation of gene testing results prior to starting GCRA. Two-year results were analyzed. For those pts found to have deleterious mutations, charts were reviewed to confirm the gene affected, and the length of time between cancer dx and GCRA. Pts more than one year out from dx were designated as cancer survivors. Results: After 2 years, 490 pts had gone through gene testing after GCRA, and 85 were found to carry deleterious mutations. These data were compared to the previous three years when pts had been referred to GC ( Table ). Both the number of pts tested and the number with mutations in yrs 2007–8 were approximately 400% of the numbers for yrs 2005–06. Of the 85 pts with mutations, 51 (60%) were cancer survivors. Their median time from diagnosis was 5.5 yrs (range 1–25). 75/85 (88%) mutations were in a BRCA gene. Conclusions: This oncologist-centered model proved to be very effective in identifying mutation carriers, particularly among cancer survivors in whom the hereditary syndrome had been previously overlooked. Acceptance of this approach by pts, physicians, and payers has been extremely high. This model should be considered by oncology practices wanting to add GCRA to their service lines.

[Table: see text]

[Table: see text]

Fetoscopic Laser Ablation for Twin-to-Twin Transfusion Syndrome: A 15-year Review of Perinatal Survival

Objective Twin to twin transfusion syndrome (TTTS) complicates 5-15% of monochorionic twin pregnancies and untreated is associated with a 90% mortality rate. The aim was to present the perinatal survival of patients with TTTS treated with laser ablation, by a national fetal medicine team. Methods This was a review of all cases of TTTS treated with fetoscopic laser ablation performed from March 2006 through to December 2020. All patients treated with fetoscopic laser were identified from the hospital database. The perinatal outcomes for the overall cohort and the individual Quintero stages were determined. Results A total of 155 cases of TTTS underwent fetoscopic laser ablation during the study period. The median gestational age at diagnosis was 19+1 weeks, with a mean growth discordance of 23.6%. The Quintero stage at diagnosis was: Stage 1 6.5% (10/155), Stage 2 49% (76/155), Stage 3 38.7% (60/155), Stage 4 5.8% (9/155). There was at least one survivor in 83.2% (129/155) of pregnancies, with dual survival in 52.9% (82/155). An increase in the rate of any survivor was observed from 75% (2006-2014) to 94% (2014-2020) (p<0.05). Dual survival decreased with increasing Quintero Stage (p<0.05). 80.6% (125/155) of pregnancies delivered prior to 34+6 weeks gestation. Conclusion Fetoscopic laser ablation is the recommended first line treatment for severe TTTS. We observed a survival rate of at least one twin in 83.2% pregnancies which is comparable to internationally published data on single-centre outcomes.

Dietary therapy in abdominal aortic aneurysm - Insights from clinical and experimental studies

Abdominal aortic aneurysm (AAA) is a prevalent vascular disease with high mortality rates upon rupture. Despite its prevalence in elderly populations, there remain limited treatment options; invasive surgical repair, while risky, is the only therapeutic intervention with proven clinical benefits. Dietary factors have long been suggested to be closely associated with AAA risks, and dietary therapies recently emerged as promising avenues to achieve non-invasive management of a wide spectrum of diseases. However, the role of dietary therapies in AAA remains elusive. In this article, we will summarize the recent clinical and pre-clinical efforts in understanding the therapeutic and mechanistic implications of various dietary patterns and therapeutic approaches in AAA.

Prostate specific antigen and acid phosphatase-reactive cells in cystitis cystica and glandularis

Cystitis cystica (CC) and cystitis glandularis (CG) are common in the urothelium lining the bladder neck and trigone. Because some cases of CG show histologic features strikingly similar to prostatic acini, we hypothesized that some such foci may represent prostatelike metaplasia in the urinary bladder. Forty surgical and autopsy bladder specimens (23 males, 17 females) showing CC or CG were studied using anti-prostate specific antigen and anti-prostate specific acid phosphatase antibodies. Fourteen (35%) of these 40 cases showed positive staining for prostate specific antigen or prostate specific acid phosphatase or both in CC or CG foci. Among these were five female patients. The findings indicate that bladder epithelium is capable of undergoing prostatelike metaplasia and lend support to the hypothesis that the adult bladder stroma closest to the prostate may exert inductive influences on the overlying epithelium to show prostatelike metaplasia.