The topology of early- and late-replicating chromatin in differentially decondensed chromosomes

In this study we used a novel technique to reveal both longitudinal and transverse differentiation within mammalian mitotic chromosomes. Structural changes in chromosomes that we term ‘differential decondensation’ were produced in cells that were first incubated in hypotonic medium (15% Hanks’ solution), then adapted to normotonic conditions and thereafter exposed to a second short hypotonic shock. Such a double hypotonic treatment (DHT) is not critical for cell viability, but considerably elongates the G2 phase of the cell cycle. Giemsa staining of differentially decondensed chromosomes corresponds to standard G-banding, but does not need the standard post-fixation treatment. Using ‘dynamic’ BrdU banding, we show that such ‘differential’ staining is a result of differential resistance of the R- and G-bands to DHT. Thus, early-replicating foci, markers of R-bands, are localized in the peripheral chromatin halo, whereas late-replicating foci, corresponding to G-bands, remain associated with the axial regions of chromatids. Remarkably, despite these major changes in the structure of the chromosomal bands, the replication foci still preserve their discrete structure.     

Retrospective multicentre study on mechanical and enzymatic preparation of fresh and cryopreserved testicular biopsies

BACKGROUND: Isolation of sperm suitable for ICSI from fresh or frozen-thawed testicular sperm extraction (TESE) can be facilitated by mechanical or enzymatic processing of the samples. METHODS: A retrospective multicentre study was initiated to compare these two approaches. Eleven German centres provided data on their TESE cycles performed during the period 1996/1997. Quality of retrieved sperm, fertilization rates of injected oocytes, embryo quality, resulting pregnancy rates and evolution of pregnancies were evaluated. RESULTS: The percentage of cycles with at least some motile sperm available for injection was higher after mechanical preparation. Independent of the preparation method, fertilization rates were higher for motile compared with immotile sperm or elongated spermatids in all groups and in general higher for cryopreserved versus fresh samples. Embryo quality was significantly better after injection of motile sperm for all treatments and in particular after enzymatic versus mechanical processing of biopsies. Pregnancy rates were identical for embryos derived from sperm prepared mechanically or enzymatically from fresh or cryopreserved testicular samples. The abortion rate (32/172, 18.6%) and the rate of multiple implantations (32/140, 22.9%) were not different from results reported in the literature for ICSI using ejaculated sperm. CONCLUSION: In this retrospective multicentre study, no unequivocal advantage of one over the other preparation method could be identified in 839 ICSI cycles using testicular sperm from 549 patients.     

The influence of intermolecular interactions on the polymerization, 1·1H NMR investigation of solutions of naphthalene and methyl methacrylate,of 2-naphthyl methacrylate,and of 1-naphthyl methacrylate

The solutions of methyl methacrylate (MMA) and naphthalene (N), of 2-naphthyl methacrylate (2-NM) and of 1-naphthyl methacrylate (1-NM) in chloroform, acetone, acetonitrile and N,N-dimethylformamide are studied by ¹H NMR spectroscopy. In chloroform and in pure MMA, N causes a shift of the signal of the high field vinyl proton H_a of MMA to higher field, whereas in acetone and acetonitrile the signal of H_a has the τ-value for MMA in the absence of N. The H_a signals of 2-NM and 1-NM in acetone, acetonitrile and N,N-dimethylformamide shift downfield as compared with those in chloroform. The τ-value of the downfield vinyl proton H_b does not vary with a change of the solvent. The separation of the vinyl signals Δ=τ(H_a)—τ(H_b) becomes equal to that of pure MMA. The formation of 1:1 complexes between the electron donating naphthalene ring and the electron accepting methacrylic double bond is assumed. The stability constant of the MMA-N complex is 0,22 1.mol^?1. Some structures for the complexes are proposed on the basis of molecular models of the monomer molecules. The results confirm the known theories for the influence of the solvents in radical polymerization of MMA. They can explain the kinetic changes of polymerization of 2-NM and 1-NM.     

Epidemiology of achondroplasia: A population‐based study in Europe

Achondroplasia is a rare genetic disorder resulting in short‐limb skeletal dysplasia. We present the largest European population‐based epidemiological study to date using data provided by the European Surveillance of Congenital Anomalies (EUROCAT) network. All cases of achondroplasia notified to 28 EUROCAT registries (1991–2015) were included in the study. Prevalence, birth outcomes, prenatal diagnosis, associated anomalies, and the impact of paternal and maternal age on de novo achondroplasia were presented. The study population consisted of 434 achondroplasia cases with a prevalence of 3.72 per 100,000 births (95%CIs: 3.14–4.39). There were 350 live births, 82 terminations of pregnancy after prenatal diagnosis, and two fetal deaths. The prenatal detection rate was significantly higher in recent years (71% in 2011–2015 vs. 36% in 1991–1995). Major associated congenital anomalies were present in 10% of cases. About 20% of cases were familial. After adjusting for maternal age, fathers >34 years had a significantly higher risk of having infants with de novo achondroplasia than younger fathers. Prevalence was stable over time, but regional differences were observed. All pregnancy outcomes were included in the prevalence estimate with 80.6% being live born. The study confirmed the increased risk for older fathers of having infants with de novo achondroplasia.     

Effect of dihydroergosine (DHESN) on the serotoninergic system and behaviour: Is DHESN a new antidepressive agent?

Acute (50.0 mg/kg) and repeated (0.1–10.0 mg/kg) administration of dihydroergosine (DHESN) to rats over 5 days lowered the concentration of 5-HIAA in the brain. DHESN given acutely increased the brain 5-HT in p-CPA-treated animals and diminished the probenecid-induced increase in brain 5-HIAA. In pargyline-treated rats DHESN enhanced the 5-HT/5-HIAA ratio. DHESN administered to rats repeatedly over 5 days decreased the level of 5-HT in blood platelets, and in vitro at concentrations of 10^-4 M and 10^-3 M inhibited the uptake of [¹⁴C]-5-HT in platelets. DHESN (10.0–100.0 mg/kg) potentiated the 5-HT syndrome produced in rats by pargyline and 5-HTP. This potentiation was blocked with cyproheptadine but not with haloperidol. DHESN (1.0 and 10.0 mg/kg) lowered the locomotor activity of rats and 10.0 mg/kg DHESN also reduced the duration of immobility in rats forced to swim in a restricted space. The results indicate that DHESN, like antidepressants, decreases the turnover of serotonin in the brain and potentiates the 5-HT-mediated behaviour. This might suggest that the drug should be further investigated for its potential antidepressive properties.     

Offshore telemedicine emergency service: a 1-year experience

Journal of Public Health - Offshore wind energy is a fast growing market. Accordingly, a correspondingly large number of employees are working at the wind farms. Owing to the harsh operating...     

The impact of nurse staffing levels on nursing-sensitive patient outcomes: a multilevel regression approach

The European Journal of Health Economics - The goal of this study is to provide empirical evidence of the impact of nurse staffing levels on seven nursing-sensitive patient outcomes (NSPOs) at the...     

Incidence of hospital‐acquired pressure injury: A cohort study of adults admitted to public and private hospitals in Sao Paulo,Brazil

This study aimed to estimate the incidence of hospital‐acquired pressure injury (PI) and its risk factors in inpatient and intensive care units of five hospitals (two public and three private) in the city of Sao Paulo, Brazil. A 6‐month follow‐up prospective cohort study (n = 1937) was conducted from April to September 2013. Baseline and follow‐up measurements included demographic and care information, as well as risk assessments for both undernutrition (NRS‐2002) and PI (Braden scale). Poisson regression with robust variance was used for data analysis. A total of 633 patients (32.60%) showed risk for PI. The incidence rate of PI was of 5.9% (9.9% in public hospitals vs 4.1% in private hospitals) and was higher in intensive care units, compared to inpatient care units (10% vs 5.7%, respectively). Risk for PI increased with age (RR = 1.05; 95% CI 1.04‐1.07); was higher in in public hospitals, compared to private hospitals (RR = 4.39; 95% CI 2.92‐6.61); in patients admitted for non‐surgical reasons compared to those admitted for surgical reasons (RR = 1.91; 95% CI 1.12‐3.27); in patients with longer hospital stays (RR = 1.04; 95% CI 1.03‐1.06); high blood pressure (RR = 1.76; 95% CI 1.17‐2.64); or had a risk for undernutrition (RR = 3.51; 95% CI 1.71‐7.24). Higher scores in the Braden scale was associated with a decreased risk of PI (RR = 0.79; 95% CI 0.75‐0.83). The results of our study indicate that 5.9% of all patients developed PI and that the most important factors that nurses should consider are: patient age, care setting, length of hospitalization, comorbidities, reason for admission and nutrition when planning and implementing PI‐preventative actions.     

Rheumatic carditis in the adult. Anatomoclinical correlation

The histologic findings of 325 necropsies of rheumatic patients at the National Institute of Cardiology in Mexico, between 1980-1985 were studied forty five of them had Aschoff nodules plus valvular inflammation-Out of these 45 cases two groups were formed: children-adolescent group (24 cases) and an adult group (21 cases). The clinical, histologic and laboratory findings were compared. Clinical records were reviewed searching for history of rheumatic fever. Active rheumatic fever was suspected in 16 patients in the younger group (67%) and only in 3 adults (14.2%). As far as Jones' criteria is concerned, the most common finding was carditis, principally in the younger group (83%). In the adult group, it appeared in 50% of the patients. All other criteria were only occasionally seen or could not be identified during the patients lifetime. The most common laboratory finding which could suggest active rheumatic fever were: a high levels of anti-streptolysin in younger patients (95%) and elevation of erythro-sedimentation in adults (83%). We conclude that in active rheumatic fever of the adult; Jones criteria are not met, so the illness is difficult to recognize, and there is clinical-histologic discrepancy. In this context the disease has a "silent" evolution.