Magneto-structural correlations in oxalate-bridged Sr(ii)Cr(iii) coordination polymers: structure, magnetization, X-band, and high-field ESR studies.

The results of high-field electron spin resonance (HF-ESR) spectroscopy on the title 1D coordination polymers at frequencies up to 415 GHz, supported by X-ray diffraction, thermal, magnetic susceptibility, and X-band (10 GHz) ESR studies, are presented. The heterometallic compounds {SrCr2(phen)2(C2O4)4}·H2O (SrCrPhen) and {SrCr2(bpy)2(C2O4)4(H2O)}·5H2O (SrCrBpy) (phen = 1,10-phenanthroline, bpy = 2,2'-bipyridine) were synthesized. Structural analysis revealed double oxalate-bridged zigzag Sr-Cr chains while magnetic susceptibility studies showed paramagnetic behaviour of the complexes. HF-ESR spectroscopy data were analysed with a relevant spin-Hamiltonian, yielding the g, D and E parameters of the Cr(iii) ions. Both complexes showed small magnetic easy-axis type anisotropy with |D| ∼ 1 K; SrCrBpy has uniaxial anisotropy while SrCrPhen has biaxial anisotropy. HF-ESR studies have enabled us to establish rational magneto-structural correlations and revealed significant differences between very similar crystal structures. Additionally, the ability of SrCrPhen and SrCrBpy to be single-source precursors for the formation of Sr-Cr oxides was investigated.

Basolateral ion transporters involved in colonic epithelial electrolyte absorption, anion secretion and cellular homeostasis.

Electrolyte transporters located in the basolateral membrane of the colonic epithelium are increasingly appreciated as elaborately regulated components of specific transport functions and cellular homeostasis: During electrolyte absorption, Na(+) /K(+) ATPase, Cl⁻ conductance, Cl⁻/HCO3⁻ exchange, K(+) /Cl⁻ cotransport and K(+) channels are candidates for basolateral Na(+) , Cl⁻ and K(+) extrusion. The process of colonic anion secretion involves basolateral Na(+) /K(+) /2Cl⁻ , and probably also Na(+) /HCO3⁻ cotransport, as well as Na(+) /K(+) ATPase and K(+) channels to supply substrate, stabilize the membrane potential and generate driving force respectively. Together with a multitude of additional transport systems, Na(+) /H(+) exchange and Na(+) /HCO3⁻ cotransport have been implicated in colonocyte pH(i) and volume homeostasis. The purpose of this article is to summarize recently gathered information on the molecular identity, function and regulation of the involved basolateral transport systems in native tissue. Furthermore, we discuss how these findings can help to integrate these systems into the transport function and the cellular homoeostasis of colonic epithelial cells. Finally, disturbances of basolateral electrolyte transport during disease states such as mucosal inflammation will be reviewed.

Hyperinsulinemia and sex hormones in healthy premenopausal women: relative contribution of obesity, obesity type, and duration of obesity.

Insulin secretion in response to an oral glucose tolerance test (OGTT) and sex hormone levels (free testosterone, androstenedione, dehydroepiandrosterone sulfate [DHEAS], estradiol, and sex hormone-binding globulin [SHBG]) were evaluated in 49 healthy obese premenopausal women (body mass index [BMI], 30 to 50.6 kg/m2) and 21 control subjects (BMI, 17.8 to 24.0 kg/m2) with normal glucose tolerance and without signs of hyperandrogenism. Obese women were divided into two groups according to waist to hip ratio (WHR): 27 subjects with upper-body obesity (WHR > 0.85) and 22 subjects with lower-body obesity (WHR < 0.8). Both fasting and glucose-induced insulin levels were higher in women with upper-body obesity than in controls (P < .001) and those with lower-body obesity (P < .001). Hyperandrogenism was observed in women with upper-body obesity, as evident by significantly elevated free testosterone (P < .05 v controls and subjects with lower-body obesity) and decreased SHBG (P < .001 v controls). The most important independent determinants of fasting insulin levels were BMI (P < .01) and the ratio of DHEAS to free testosterone (P < .01). The most important determinants of cumulative insulin response were WHR (P < .0005), duration of obesity (P < .01), and androstenedione levels (P < .01). In conclusion, in healthy obese premenopausal women without clinical signs of hyperandrogenism, a high BMI and more pronounced upper-body fat localization resulted in hyperinsulinemia and hyperandrogenism. The duration of obesity exaggerated the glucose-induced insulin level and cumulative insulin response independently of the degree of obesity and obesity type. The ratio of DHEAS to free testosterone was an independent determinant of fasting insulin concentration. Furthermore, the ratio of DHEAS to free testosterone rather than either of these androgens alone may be important in the regulation of insulin action in women.

Simulation model of defective insulin receptors as byproducts of receptor recycling.

Our simulation model assumes that the defective insulin-binding receptors in non-insulin-dependent diabetes (NIDDM) patients result from functional receptor recycling. The model is a short program written in MS DOS 5.0 Qbasic. MODEL DESIGN: Receptors with intracellular portions damaged in the process of recycling are considered defective since they bind insulin but do mediate insulin effects, or recycle. Their occurrence depends on the average activation rate of functional receptors. The insulin-binding receptors (defective and functional) are objects of slow and time-dependent turnover defined by the turnover rate. Recycled receptors rejoin functional receptors or enter the pool of defective receptors. The waste in the functional receptors' pool is covered by a limited amount of newly synthesized receptors. The defective receptors often accumulate in cases of increased activation of functional receptors. SIMULATION RESULTS: The insulin-binding receptor quantity is determined, in the model, only by the number of newly synthesized receptors, reflecting the intensity of insulin stimulation. Synthesis is increased following variable insulin stimulations and decreased after sustained, intensive insulin stimulation. The number of functional receptors inversely reflects the average activation rate of functional receptors compared with the insulin-binding receptors turnover rate. High activation rates can diminish the proportion of functional receptors to less than 5% of that of all insulin-binding receptors. The model predicts that cells bearing only functional receptors show progressively shortened half-lives of receptors, reflecting the receptor activation intensity. On the other hand, cells bearing both defective and functional receptors show stable receptors' half-lives (20-36% of the defective receptors' half-life). Simulation results suggest that reduced functional receptor proportions in NIDDM patients might reflect the imbalance between the activation of functional receptors and the slow catabolism of defective receptors.

Cor triatriatum dextrum--an unusual variant of triatrial heart.

The present report describes a rare case of triatrial heart, cor triatriatum dextrum in a 31-year-old woman in whom the anomaly was incidentally detected by radionuclide angiocardiography. Subsequent assessment with two-dimensional echocardiography and right heart catheterization confirmed the presence of a membrane subdividing the right atrium into two distinct chambers. To the best of our knowledge, this is the only case in which this cardiac anomaly was demonstrated by radionuclide technique.

Haemodynamic changes and exercise tolerance in dialysis patients treated with erythropoietin.

The aim of our study was to evaluate cardiovascular function at rest and during exercise in dialysis patients before and after treatment with Epo and to examine the changes in left ventricular mass as the consequence of treatment for anaemia. We applied echocardiography and radionuclide ventriculography at rest and after exercise in our research. Following treatment with Epo there was a decrease in the initially high cardiac output (CO) and cardiac index (CI) from 7.5 to 6.31/min and from 4.3 to 3.61/min/m2 respectively. No changes were noted in mean diastolic (DPB) and mean blood pressure (MBP), as well as the initially increased peripheral resistance index (TPRi) of 2582.3 +/- 2097.3 dyn-s-cm-5.m2. Nevertheless, end-diastolic (EDV) and end-systolic (ESV) volume were significantly decreased (P < 0.05), but the ejection fraction (EF) remained unchanged (73.9%). The decrease in the mean values for left ventricular mass (LVM) was significant only within the subgroup of dialysed patients who initially had larger left ventricular mass (P < 0.01). The functional capacity of the CV system measured during exercise increased from four metabolic equivalents (METs) to 6 METs (P < 0.01). A significant increase in blood volume was also observed following treatment of anaemia. The haemodynamic consequences of Epo therapy for the treatment of anaemia were quite positive. However, we would like to point out certain concerns regarding the dialysed patients with initially lower values for left ventricular mass and cardiac output, since the patients within this group developed left ventricular hypertrophy and an increase in cardiac output.

[Premalignant and malignant changes in the uterine cervix in women younger than 30 years]. / Premaligne i maligne promjene na grlicu maternice u zena mladih od 30 godina.

From 1974 to 1983, 124.471 cervico-vaginal smears after Papanicolaou were analysed. Group I and II findings numbered 97.06%, group III 2.28%, group IV 0.54%, and group V 0.12%. Most findings of groups III and IV related to women in their forties (32%), then to those in the fifties (28.2) and in the thirties (26%). Out of 1522 group III women, 261 were histologically examined: there were 78 dysplasias, 108 carcinomas in situ, 27 invasive carcinomas, and 48 benign changes. Out of 317 group IV women, there were 33 benign changes, 66 dysplasias, 158 carcinomas in situ, and 60 invasive carcinomas. Out of 78 group V women, there were 7 benign changes and dysplasias each, 17 carcinomas in situ, and 47 invasive carcinomas. Most dysplasias and carcinomas in situ were found in women in their forties (39.9), a smaller number in women in their thirties (29.4%), and the smallest number in women in their fifties (22.5%). Out of all invasive carcinomas, the highest number was found in women in their fifties (32.09%), the peak being about ten years later than that relating to dysplasias and carcinomas in situ. The conclusion is that the screening of the uterine cervix should start already at the time of defloration.

[Prevention of vaginal prolapsus after abdominal hysterectomies (author's transl)]. / Prevencija prolapsa vaginalnog bataljka nakon abdominalnih histerektomija.

According to foreign authors, the prolapsus vaginae occurs in 0.01--0.5% cases after abdominal hysterectomy. It has been proved that the prolapsus can be prevented if an adequate operational technique is applied. The authors describe their own operational method consisting of intrafascial hysterectomy after Aldridge and Meredith, followed by the fixation of the vaginal vault with round ligaments. During an eleven-year period (1969-1979), 982 abdominal hysterectomies using this method were performed without a single case of prolapsus of the vaginal vault.