The Wintertime Southern Hemisphere Split Jet Bals-Elsholz, Teresa M.; Atallah, Eyad H.; Bosart, Lance F. ...
Journal of climate,
11/2001, Letnik:
14, Številka:
21
Journal Article
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A persistent feature of the Southern Hemisphere upper-level time-mean flow is the presence of a split jet across the South Pacific east of Australia during the austral winter. The split jet is ...composed of the subtropical jet (STJ) on its equatorward branch and the polar front jet (PFJ) on its poleward branch. The NCEP–NCAR reanalysis is used to investigate the structure and evolution of the split jet. Results show that the presence/absence of the PFJ determines the degree of split flow, given that the STJ is a quasi-steady feature. A split-flow index (SFI) is developed to quantify the variability of the split jet, in which negative values represent strong split flow and positive values nonsplit flow. Correlations with teleconnection indices are investigated, with the SFI positively correlated to the Southern Oscillation index and negatively correlated to the Antarctic oscillation.
The SFI is used to construct composites of heights, temperature, and wind for split-flow and non-split-flow days. The composites reveal that relatively cold conditions occur in the South Pacific in association with non-split-flow regimes, and split-flow regimes occur when relatively warm conditions prevail. In the latter situation cold air bottled up over Antarctica helps to augment the background tropospheric thickness gradient between Antarctica and the lower latitudes with a resulting increase in the thermal wind and the PFJ. It is surmised that frequent cold surges out of Antarctica moving into the South Pacific are associated with non-split-flow regimes. In this context, the variability of the split jet responds to large-scale baroclinic processes and is further modulated by synoptic-scale disturbances.
Left ventricular hypertrophy (LVH) is a strong predictor of cardiovascular disease and is common among patients with type 2 diabetes. However, no systematic screening for LVH is currently recommended ...for patients with type 2 diabetes. The purpose of this study was to determine whether NT-proBNP was superior to 12-lead electrocardiography (ECG) for detection of LVH in patients with type 2 diabetes.
Prospective cross-sectional study comparing diagnostic accuracy of ECG and NT-proBNP for the detection of LVH among patients with type 2 diabetes. Inclusion criteria included having been diagnosed for > 5 years and/or on treatment for type 2 diabetes; patients with Stage 3/4 chronic kidney disease and known cardiovascular disease were excluded. ECG LVH was defined as either the Sokolow-Lyon or Cornell voltage criteria. NT-proBNP level was measured using the Roche Diagnostics Elecsys assay. Left ventricular mass was assessed from echocardiography. Receiver operating characteristic curve analysis was carried out and area under the curve (AUC) was calculated.
294 patients with type 2 diabetes were recruited, mean age 58 (SD 11) years, BP 134/81 ± 18/11 mmHg, HbA 1c 7.3 ± 1.5%. LVH was present in 164 patients (56%). In a logistic regression model age, gender, BMI and a history of hypertension were important determinants of LVH (p < 0.05). Only 5 patients with LVH were detected by either ECG voltage criteria. The AUC for NT-proBNP in detecting LVH was 0.68.
LVH was highly prevalent in asymptomatic patients with type 2 diabetes. ECG was an inadequate test to identify LVH and while NT-proBNP was superior to ECG it remained unsuitable for detecting LVH. Thus, there remains a need for a screening tool to detect LVH in primary care patients with type 2 diabetes to enhance risk stratification and management.
Zusammenfassung
Patientinnen nach erfolgreicher Sterilitätstherapie sind Risikoschwangere. Es kommt häufiger zu Schwangerschaftskomplikationen, die typischerweise mit einem Gestationsdiabetes (GDM) ...assoziiert sind und angeborene potenzielle Gesundheitsrisiken wie Adipositas und Diabetes mellitus bei den Wunschkindern bedeuten können. Fast jede Sterilitätspatientin hat anamnestische GDM-Risikofaktoren und auch bei Normalgewicht sehr häufig bereits feststellbare Störungen im Glukosestoffwechsel und in der Insulinwirkung. Die Optimierung des Glukosestoffwechsels und der Abbau einer Insulinresistenz durch Ernährungsumstellung, Bewegung und Metformin führen nicht nur zu einer Verbesserung der Eizellreifung und Embryoentwicklung. Bei jeder vierten Kinderwunschpatientin tritt so schon vor einer geplanten Behandlung mit Techniken der assistierten Reproduktion („assisted reproductive technology“ ART) eine Schwangerschaft ein. Wird ab Beginn einer Schwangerschaft, also beim Embryotransfer im ART-Zyklus, auf einen GDM getestet, kann in mindestens 70 % der Fälle ein früh einsetzender GDM (FREGDM) diagnostiziert werden. Erfolgt die Therapie durch Schwerpunktdiabetologen unverzüglich, kann die Schwangerschaftsrate gesteigert und die Chance auf die Spontangeburt eines gesunden Kindes erhöht werden. Die GDM-Leitlinie bezieht sich überwiegend auf fortgeschrittene Schwangerschaften ab dem zweiten Trimenon, nicht aber auf die Diagnostik und Therapie eines FREGDM. Daher sollten bei der aktuellen Überarbeitung die Kinderwunschsituation und die Phase der Embryonalentwicklung in der Frühschwangerschaft berücksichtigt werden.
Summary
The partial androgen deficiency in aging male (PADAM) has been of great interest to investigators and the public in the last few years. For males, androgens are said to be essential for the ...maintenance of quality of life (QoL) but there are no data available with respect to QoL and PADAM yet. In order to evaluate changes of individual well‐being of males older than 50 years and with subnormal levels of free testosterone (FT) (<200 pmol l−1), these men were asked to fill in a questionnaire regarding QoL. The objective of this study was to compare age‐matched males with androgen deficiency (group 1; n = 24) and normoandrogenic elderly men (group 2; n = 24) with respect to QoL and somatic indicators of the endocrine status. Participants suffered from benign prostatic hyperplasia (BPH) and were hospitalized for prostate surgery. Health‐related QoL was assessed by the SF‐12 Health Survey, including the physical health index and the mental health index. The SF‐12 was enlarged by the scales ‘vitality’ and ‘psychological well‐being’ of the SF‐36. Additionally, patients were asked about social and clinical items. There were no statistically significant differences between the two groups regarding social and clinical parameters. The physical health index was reduced in group 1 (P < 0.05; effect size was medium (d = 0.57)) whereas the mental health index was similar in both groups. The correlation between the two health indices was very low and not statistically significant (r = 0.05, P = 0.72). Patients of group 1 described a lower vitality compared to group 2 (P < 0.05), but no differences could be observed regarding psychological well‐being. Therefore, androgen‐deficient patients seem to have the impression of a reduced physical ability. Our data emphasize that the subjective description of health‐related aspects of QoL is a very sensitive methodological approach to discover psychological differences between patients. For the differentiation between androgen‐deficient patients and those with normal testosterone levels the physical health index seems to be more sensitive than the mental health index. A question of interest is whether this difference remains detectable if testosterone is supplemented to androgen‐deficient men. Whether testosterone supplementation is beneficial to these patients has to be carefully considered.
Abstract
Monochorionic twins are usually monozygotic and thus usually have the same sex. A case of monochorionic diamniotic twins following IVF/ICSI and laser treatment of the zona pellucida ...(“assisted hatching”) is presented in which partial embryo amalgamation appears to have occurred. Discordant sex between the twins was suspected on detailed antenatal ultrasound at 13 + 3 weeks gestation and was confirmed on subsequent examinations. The sexual phenotype at birth was female for one twin and male for the other. Placental histology confirmed the monochorionic, diamniotic situation. Cytogenetic analysis of both twins was carried out postpartum on various tissues. On karyotyping of blood lymphocytes the male and female twins each had one mosaic of male and female cells. Oral mucosal cells showed normal male and female karyotypes respectively. Analysis of urothelium showed a normal result for the male infant, and a weak gonosomal mosaic with an XX and XY constellation for the female infant. At least for blood lymphocytes, a diagnosis of chimerism was proven.
Polycystic ovary syndrome (PCOS) and/or insulin resistance (IR) are frequent conditions in women choosing assisted reproduction techniques (ART). However, infertility work-up has to include testing ...of insulin sensitivity to diagnose IR. It was the aim of the study to analyze the frequency of impaired glucose tolerance (IGT) or gestational diabetes (GD) in the first weeks of gestation after ART in women receiving metformin.
This study included 107 women who were seeking ART under the pretreatment of metformin for PCOS, confirmed IR, recurrent spontaneous miscarriages (RSA) or other fertility disorders. They were examined for prepregnancy health parameters (weight, glucose tolerance). When pregnancy was confirmed a 75 g oral glucose tolerance test (OGTT) was conducted between the 5(th) and 7(th) week of gestation.
A high rate of GD or IGT already was observed in the first weeks of pregnancy in our cohort under metformin treatment. The predominant risk factor for diagnosed early onset of IGT or GD (58 cases) was PCOS (p=0.014). The frequency of GD was the highest in the subgroup with prepregnancy confirmed IR not fulfilling the criteria of PCOS (55%); it was 40.6% in PCOS women and 26.1% in women neither exhibiting IR nor PCOS.
Women seeking ART and being treated with metformin still show a very high rate of GD or IGT after achieving pregnancy by ART. Therefore in women undergoing ART screening for GD should be performed as soon as pregnancy is confirmed to avoid miscarriages due to overlooked uncontrolled glucose metabolism.
Microinjection is established as the method of choice in the treatment of severe male factor infertility as well as in azoospermic patients. Recent studies have shown that fertilization and cleavage ...can be achieved by injection of ejaculated as well as testicular elongated spermatids into oocytes. Here we report on the two first pregnancies worldwide resulting from elongated spermatid injection from frozen-thawed testicular tissue. Four patients with complete Sertoli cell-only syndrome (SCOS) and two with spermatogenetic maturation arrest were included in our microinjection programme. Tissues from open testicular biopsies were cryopreserved until the time of follicle puncture. A total of 67 oocytes were harvested. In the two patients with maturation arrest, cryopreserved elongated spermatids were successfully injected, while in two of the other four SCOS patients only cryopreserved round spermatids were available to be injected into the oocytes. Out of 18 injected oocytes, 10 were fertilized in the first group, while nine out of 49 injected oocytes showed fertilization and cleavage in the second group. Two clinical pregnancies were achieved with elongated spermatids from frozen-thawed testicular tissue, while no pregnancy was established in the case of round spermatids. This study confirms that fertilization, cleavage and pregnancy can be successfully achieved in cases with spermatogenetic maturation arrest by injecting cryopreserved elongated spermatids into oocytes. The literature on pregnancies following spermatid injection, as well as the problems using this technique and possible risks, are discussed.
Summary
Male infertility as a result of isolated congenital bilateral absence of the vas deferens (CBAVD) is one primary genital form of cystic fibrosis (CF) and occurs in 1–2% of infertile men. ...Assisted fertilization in patients with CBAVD increases the risk of transmitting mutations in the CF gene. We developed a rational approach to genetic CF testing in infertile men. A total of 282 infertile male patients were screened for the most common CF mutations (ΔF508, R117H, IVS8‐5T). Clinical data including medical history, examination, semen analysis, sweat tests, karyotypes and hormonal values were analysed. We identified 23 patients carrying mutations in the CF gene (ΔF508: 10 patients; R117H: six patients; IVS8‐5T: 11 patients). Two patients were compound heterozygote for ΔF508/R117H, two others for ΔF508/IVS8‐5T. Correlating these molecular analyses with the clinical data pertaining to serum follicle‐stimulating hormone concentration, semen pH, sperm count and total testicular volume, we were able to develop a score with a high specificity (98.4) for the presence of a cystic fibrosis transmembrane conductance regulator (CFTR) mutation, but only with a low sensitivity (positive post‐test likelihood: 62.5%; negative post‐test likelihood: 6.3%). With regard to the low sensitivity and the high number of CFTR mutations found in this heterogeneous group of infertile men, we still recommend genetic CF testing before assisted fertilization.
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