The prediction of far-infrared spectra for planetary nitrile ices using periodic density functional theory with comparison to thin film experiments.

Future spacecraft missions to planetary systems, Trans-Neptunian objects, and cometary bodies could implement far-infrared surveys to confirm the presence of condensed-phase species via their unique lattice features. For composite molecular ices of astrophysical significance, laboratory reference spectra are required to provide absorption coefficients used to quantify solid-state abundances. However, due to strong intermolecular interactions in polar ice systems, laboratory data of mixed-phase ices are difficult to interpret. In this study we have applied periodic density functional theory code to model bulk molecular crystals. This method allows for more accurate simulation of thin-film spectra than approaches simulating small clusters. For this proof-of-principle study on a series of pure nitrile ices of planetary interest, our simulated far-infrared spectra show excellent agreement to data from thin film studies performed at the Australian Synchrotron (crystalline acetonitrile and propionitrile) and to previously published spectra (hydrogen cyanide, acrylonitrile, cyanoacetylene, and cyanogen). The combined theoretical and experimental approach has provided a new explanation for the asymmetric profile of the hydrogen cyanide lattice feature and a more systematic assignment of nitrile ice absorption bands to low-frequency lattice modes. We nominate prominent absorption features for the detection of crystalline nitrile carriers located on planetary surfaces.

Health-related quality of life of survivors of childhood acute lymphoblastic leukemia: a systematic review.

PURPOSE: Acute lymphoblastic leukemia (ALL) survivors are the largest group of childhood cancer survivors; however, their risk for late effects is high. Cancer-related late effects have the potential to compromise health-related quality of life (HRQL) long into survivorship. None of the reviews so far have focused on ALL solely, but described HRQL for all childhood cancers. We aimed to identify ALL survivors at risk for poor HRQL and identify possible risk factors. METHOD: Following PRISMA guidelines, we performed a systematic review, searching published literature in Pubmed, PsycInfo, Embase, and the Cochrane database including all publications up to December 16, 2016. Two independent reviewers (JV and ER) screened eligible articles and assessed article quality. RESULTS: We found 31 studies representing 4356 survivors and 901 proxies. Thirteen studies found worse, eight found no difference, and three better, overall HRQL scores compared with healthy controls or norms. ALL survivors typically had better overall HRQL scores than survivors of other childhood cancers. Clinical variables (e.g., treatment received) were not consistently associated with HRQL; however, experiencing worse late effects was associated with lower HRQL. Survivor and parent socio-demographic factors and psychological factors such as resilience and depression were also associated with HRQL. CONCLUSION: ALL survivors appeared to have worse or equivalent HRQL compared with controls, but better HRQL than survivors of other cancer types. However, studies reported a wide variability in HRQL and potential risk factors for poor HRQL. Measuring ALL survivors' HRQL longitudinally and comprehensively assessing potential risk factors might identify future avenues to intervene early.

Infrared characterisation of acetonitrile and propionitrile aerosols under Titan's atmospheric conditions.

Pure, crystalline acetonitrile (CH3CN) and propionitrile (CH3CH2CN) particles were formed in a collisional cooling cell allowing for infrared (IR) signatures to be compiled from 50 to 5000 cm-1. The cell temperature and pressure conditions were controlled to simulate Titan's lower atmosphere (80-130 K and 1-100 mbar), allowing for the comparison of laboratory data to the spectra obtained from the Cassini-Huygens mission. The far-IR features confirmed the morphology of CH3CN aerosols as the metastable ß-phase (monoclinic) ice, however, a specific crystalline phase for CH3CH2CN could not be verified. Mie theory and the literature complex refractive indices enabled of the experimental spectra to be modelled. The procedure yielded size distributions for CH3CN (55-140 nm) and CH3CH2CN (140-160 nm) particles. Effective kinetic profiles, tracing the evolution of aerosol band intensities, showed that condensation of CH3CH2CN proceeded at twice the rate of CH3CN aerosols. In addition, the rate of CH3CH2CN aerosol depletion via lateral diffusion of the particles from the interrogation volume was approximately 50% faster than that of CH3CN. The far-IR spectra recorded for both nitrile aerosols did not display absorption profiles that could be attributed to the unassigned 220 cm-1 feature, which has been observed to fluctuate seasonally in the spectra obtained from Titan's atmosphere.

Structural, vibrational, and rovibrational analysis of tetrafluoroethylene.

High resolution FTIR spectra of (13)C enriched tetrafluoroethylene (C(2)F(4)) were measured at 150 K at the Australian Synchrotron. Rovibrational transitions were assigned in the a-type symmetric and b-type antisymmetric CF(2) stretches of (12)C(13)CF(4) and (13)C(2)F(4) near 1170 cm(-1) and 1300 cm(-1), respectively. Ground vibrational state spectroscopic constants for both molecules were determined in addition to the upper state constants for ν(11) and ν(9) of (13)C(2)F(4) and ν(11), ν(2)+ν(6), and ν(5) of (12)C(13)CF(4). The ground state constants, along with those determined for the (12)C(2)F(4) isotopologue from previously published data, were used to determine a semi-experimental r(e) structure r(CC) = 132.36 ± 0.37 pm, r(CF) = 131.11 ± 0.23 pm, α(FCC) = 123.3 ± 0.3° in excellent agreement with ab initio structures. Lower resolution FTIR spectra were measured between 100 and 5000 cm(-1) at room temperature and band centres obtained for all modes of the three isotopologues; although only 5 out of 12 modes in (12)C(2)F(4) and (13)C(2)F(4) are infrared (IR) active, the others were inferred from combination and hot-band positions. A number of modes are observed to be infrared active only in the (12)C(13)CF(4) isotopologue due to its lower symmetry. Most notably, decoupling of the antisymmetric CF(2) motions in the two halves of (12)C(13)CF(4) results in 2 strongly IR active modes that involve motion at one carbon or the other.

Tumour seeding following percutaneous needle biopsy: the real story!

The demand for percutaneous needle biopsy is greater than ever before and with the majority of procedures requiring imaging guidance, radiologists have an increasingly important role in the diagnostic work-up of patients with suspected malignancy. All invasive procedures incur potential risks; therefore, clinicians should be aware of the most frequently encountered complications and have a realistic idea of their likelihood. Tumour seeding, whereby malignant cells are deposited along the tract of a biopsy needle, can have disastrous consequences particularly in patients who are organ transplant candidates or in those who would otherwise expect good long-term survival. Fortunately, tumour seeding is a rare occurrence, yet the issue invariably receives a high profile and is often regarded as a major contraindication to certain biopsy procedures. Although its existence is in no doubt, realistic insight into its likelihood across the spectrum of biopsy procedures and multiple anatomical sites is required to permit accurate patient counselling and risk stratification. This review provides a comprehensive overview of tumour seeding and examines the likelihood of this much feared complication across the range of commonly performed diagnostic biopsy procedures. Conclusions have been derived from an extensive analysis of the published literature, and a number of key recommendations should assist practitioners in their everyday practice.

Barriers to prenatal care in a multiethnic, urban sample.

The barriers that prevent women from obtaining prenatal care were studied in a multiethnic, primarily indigent urban population. Two thousand nine hundred eighty-seven women were delivered at the University of Miami/Jackson Memorial Medical Center from January 15 to April 10, 1988. Of these women, 227 (7.6%) did not access any prenatal care. These women formed the study group. The results indicated that the main barriers were systematic (35.5%), patient-related (35.5%), and financial (29%). Ethnic group, marital status, and education influenced access to prenatal care, whereas age did not appear to do so. Although low birth weight rates were higher in the study group, it was apparent that cultural behavior influenced birth weight, whether or not prenatal care was obtained.

A birth center affiliated with the tertiary care center: comparison of outcome.

A matched pair study compares 250 low risk women delivered in a tertiary care center with a similar group cared for and delivered in an affiliated birth center. The patients could be matched in every respect with the exception of educational background. Twenty-one percent of the birth center patients required transfer to the hospital during the intrapartum period. Differences were found in cervical dilatation upon admission and length of labor. Intermittent fetal heart auscultation was used exclusively in birth center mothers, oral fluids and light diet were allowed. The hospital group received intravenous fluids. Oxytocin augmentation was used twice as often, and the incidence of shoulder dystocia appeared significantly higher in the control group. The reasons for transfer are described. The one neonatal death was due to persistent fetal circulation.

Placental injection studies in twin gestation.

Vascular communication between placental vessels can occur when there is a fused placental mass in twin gestation. The presence of anastomotic channels can lead to the twin-twin transfusion syndrome in the fetuses. A study was conducted on 278 twin pairs to determine the incidence of vascular communication in fused twin placentas and the frequency of twin-twin transfusion syndrome. Anastomotic communication was found almost universally in monochorionic placentation and very rarely with dichorionic placentas. Twin-twin transfusion syndrome occurred uncommonly despite the high frequency of occurrence of cross-placental vascular communication. Misdiagnosis of intrauterine growth retardation in one twin can be avoided by determination of chorionicity by inspection of the placentas of twin gestation.

Blood pressure in infant twins: birth to 6 months of age.

To describe the time course of the early development genetic variance for blood pressure, a cohort of twins is being followed from birth to 1 year of age. The present interim report describes systolic and diastolic blood pressure measurements for 102 twin pairs (39 monozygotic (MZ) and 63 dizygotic (DZ) in the newborn period and at 1, 3 and 6 months of age. Mean values for both systolic and diastolic blood pressure were similar regardless of race, sex, zygosity, or chorionicity. Statistically significant genetic variance was detected for systolic blood pressure at 6 months of age but not for diastolic blood pressure at any data point. The data are consistent with the hypothesis that genetic factors that determine within-family similarities of blood pressure may be detected early in life, and support the need for further investigation of both genetic and environmental determinants of blood pressure in young populations.

Blood glucose control during pregnancy.

Pregnant diabetic women represent a unique category of patient in whom diabetic control is most desirable, since even minor degrees of hyperglycemia have adverse effects on the conceptus. In 18 insulin-dependent pregnant diabetic women (White Class B, N = 4; C, N = 5; D, N = 7; and R, N =2), we have utilized a therapeutic program consisting of intensive patient education, a multiple-component insulin regimen (two to four injections daily), careful dietary control, and meticulous balancing of food, activity, and insulin dosage, monitoring such balance with patient-determined blood glucose measurements four to seven times daily using the Dextrostix/Eyetone system. Our goals for blood glucose management have been to attain fasting levels of 60-90 mg/dl, preprandial levels less than 105 mg/dl, and postprandial levels less than 120 mg/dl, in the absence of significant hypoglycemia. We have been able to attain these goals for most of the period of monitoring in the majority of these patients, while in the others we have achieved marked improvement in diabetic control, although we did not consistently attain our goals. Despite this, there was not infrequent neonatal morbidity, including a 33% frequency of macrosomia, an 11% frequency of significant hypoglycemia, and a 22% frequency of congenital malformation. Nevertheless, all infants survived and are generally healthy, whereas only 38% of 21 previous pregnancies in these same women have eventuated in living offspring. Thus, although further refinement is clearly indicated, it appears that our approach has resulted in improved pregnancy outcome. Patient self-monitoring of blood glucose is a procedure that is relatively simple, practical, acceptable to patients, and facilitates the attainment of glycemic control.

Effects of steroids on serum lipids and serum cholesterol binding reserve.

Serum cholesterol binding reserve (SCBR) denotes the capacity of serum to solubilize additional cholesterol. It as been shown previously that a decrease of the SCBR in the presence of elevated cholesterol and/or triglyceride levels is associated with the development of coronary artery disease in man. This is a preliminary report of the effect on serum lipids and SCBR by alteration of the sex steroid environment in women. The hormonal changes associated with pregnancy appear to elevate cholesterol, triglycerides, and SCBR, SCBR being elevated to the greatest extent. No differences were observed in SCBR and serum lipids in a short-term study of premenopausal women when values prior to castration are compared with values after castration during administration of conjugated equine estrogens. In women observed over a period of over 20 weeks, who were using a combination oral contraceptive pill with 1 mg. of norethindrone and 50 or 80 mcg. of mestranol, there was a significant elevation of triglycerides, some decrease of cholesterol, and no change in the SCBR. The possible significance of these findings in relation to the risk of coronary heart disease deserves further investigation.

Asessment of fetal gestational age in high-risk pregnancies by amniotic fluid analyses and ultrasound mensuration.

Maturity studies are reported on 204 women with high-risk pregnancies. Estimates of fetal maturity were made prenatally by the use of ultrasonic measurements, the lecithin/sphingomyelin (L/S) ratio, and a gestational index based on amniotic fluid creatinine, urea nitrogen, and cytology. These estimates were compared with the neonatal pediatric estimate of maturity. The gestational score agreed with pediatric maturity to within 14 days in 95 per cent of the cases. Estimates of L/S ratio distinguished between mature and immature infants in 86 per cent of the cases. Ultrasound could estimate gestational age only to within 14 days in 75 per cent of the cases, and the disagreements were greatest where either growth retardation or macrosomia was present. However, ultrasound is more useful in estimating fetal size and abnormalities of growth pattern. An estimate of gestational age by gestational score aids management, particularly where growth retardation is present, enabling a decision about delivery to be made even though the infant is very small and has an immature L/S ratio.

Home blood glucose monitoring as an aid in diabetes management.

Home blood glucose monitoring, using Dextrostix and an Eyetone meter, has been utilized in several subcategories of patients with insulin-dependent diabetes mellitus. These include pregnant patients, anephric patients, patients undergoing weight reduction, patients with altered renal threshold for glucose reabsorption, and patients in whom diabetic regulation is difficult. Patients monitored home blood glucose continually (on a daily basis), intermittently, or only for particular problems or symptoms. Such monitoring can be practically accomplished in a manner acceptable to patients. Motivation, compliance with protocol, and an understanding of the objectives of the program are essential on the part of the patient. Home blood glucose monitoring, however, can provide an insight diabetes regulation that cannot be attained in any other way and can greatly facilitate regulation of diabetes. Such home blood glucose monitoring may increase the likelihood of achievement of a degree of control approximating euglycemia.

Intrauterine transfusion in the management of severe rhesus isoimmunization.

In the ten years between 1965 and 1974, 2227 patients with rhesus isoimmunization were seen at the Newcastle centre. The antibody titre and previous history were the basis on which patients were selected for amniocentesis and determination of the amniotic fluid bilirubin ratio. There were 288 patients with a bilirubin ratio which was greater than 1-1: of these 206 were treated by intrauterine transfusion (IUT). Evidence for the belief that the treated and untreated groups were similar is presented. The overall survival rates were 44 per cent for cases treated by intrauterine transfusion and 50 per cent for those not treated in this way. The mortality directly attributable to the procedure was at least 20 per cent and did not take into account errors of selection nor accidents associated with amniocentesis.