Pre-clinical Cushing's syndrome: an unexpected frequent cause of poor glycaemic control in obese diabetic patients

OBJECTIVE Autonomous cortisol secretion without clinical stigmata of Cushing's syndrome (CS) has been recently recognized and termed pre-clinical or sub-clinical CS. The common assumption is that CS is an extremely rare cause of uncontrolled diabetes; however, the prevalence of this entity has not been studied. We assessed the prevalence of pre-clinical CS among obese patients with uncontrolled diabetes. PATIENTS AND DESIGN (1) In a retrospective analysis, the medical records of 63 patients with endogenous CS were reviewed. (2) In a cross-sectional study, 90 obese patients (BMI >25 kg/m²) followed in a University Hospital and the local Health Fund endocrine and diabetes clinics, with poorly controlled diabetes (glycosylated haemoglobin >9%), underwent an overnight 1 mg dexamethasone suppression. In patients with non-suppressible cortisol levels (>140 nmol/l), Liddle's 2 and 8 mg dexamethasone suppression tests and imaging studies were performed. MEASUREMENTS The prevalence of poorly controlled diabetes, the major presenting symptom of CS, was assessed in the retrospective analysis. The prevalence of ‘true’ CS and the false positive rate in the overnight dexamethasone suppression test were calculated. The endocrine evaluation of the patients with pre-clinical CS and the effects of surgical cure on glycaemic control are described. RESULTS In the retrospective analysis, 11 (17.5%) had diabetes and 2 (3.2%) lacked the classic physical characteristics of the syndrome. In the cross-sectional study, 4 patients failed to suppress plasma cortisol (<140 nmol/l). In one patient the diagnosis of CS was not confirmed by a standard Liddle’s test and was therefore considered false positive. In the other 3, the diagnosis of CS was confirmed (prevalence of 3.3%, 95% confidence interval 1–9%). In all other patients the overnight cortisol suppression test was normal (cortisol level 47.3 ± 2.5 nmol/l (mean ± SEM)). After surgical treatment of CS, glycaemic control was markedly improved in all 5 patients (2 from retrospective and 3 from cross-sectional studies). CONCLUSIONS The prevalence of pre-clinical Cushing's syndrome in obese patients with poorly controlled diabetes appears to be considerably higher than previously believed. The overnight dexamethasone suppression test proved to be a simple, sensitive and highly specific screening test for Cushing's syndrome despite the presence of obesity and hyperglycaemia.     

Reconstruction of pectus excavatum with silicone implants.

The pectus excavatum deformity is characterised by a deep depression usually involving the lower one-half to two-thirds of the sternum. The indications for surgery are often aesthetic. Extensive procedures, requiring fracturing and remodelling of the chest wall skeleton are associated with high morbidity and high rate of complications. In this article we describe our renewed experience with reconstruction of mild and moderate pectus excavatum deformities with custom made prefabricated silicone implants. The fabrication of the implant and the surgical technique are described in detail. An excellent aesthetic correction of the deformity was achieved in all of the patients in our series, with high patient satisfaction rate. We conclude that with careful patient selection, artistic implant fabrication and meticulous surgical technique, this approach achieves excellent aesthetic correction with minimal morbidity and a low complication rate and therefore should maintain its place in the armamentarium of surgical techniques for reconstruction of pectus deformities.     

Use of antibiotic and analgesic drugs during lactation.

During lactation, multiple situations can arise that require maternal pharmacological treatment. Because of the many health advantages of human milk to infants, breast feeding should be interrupted only when the needed drug might be harmful to the nursing child and exposure via the breast milk will be sufficient to pose a risk. Since the majority of drugs have not been shown to cause adverse effects when used during lactation, and even temporary interruption of breast feeding can be difficult for the nursing dyad, decisions regarding maternal medication use during breast feeding should be based on accurate and up-to-date information. This article reviews available data on the most commonly used antibiotics and analgesics. The use of most antibiotics is considered compatible with breast feeding. Penicillins, aminopenicillins, clavulanic acid, cephalosporins, macrolides and metronidazole at dosages at the low end of the recommended dosage range are considered appropriate for use for lactating women. Fluoroquinolones should not be administered as first-line treatment, but if they are indicated, breast feeding should not be interrupted because the risk of adverse effects is low and the risks are justified. Paracetamol (acetaminophen), low-dose aspirin (acetylsalicylic acid) [up to 100 mg/day] and short-term treatment with NSAIDs, codeine, morphine and propoxyphene are considered compatible with breast feeding. Safer alternatives should be considered instead of dipyrone, aspirin at a dosage >100 mg/day and pethidine (meperidine). In the light of the many safe alternatives for pain control, breast-feeding mothers should not be allowed to experience pain or be made to feel that they must choose between analgesia and breast feeding.     

Human sperm chemotaxis: both the oocyte and its surrounding cumulus cells secrete sperm chemoattractants

BACKGROUND: Human sperm chemotaxis to pre-ovulatory follicular fluid is well established in vitro. However, it is not known whether the female's oocyte-cumulus complex secretes sperm chemoattractants subsequent to ovulation (for enabling sperm chemotaxis within the Fallopian tube) and, if so, which of these cell types--the oocyte or the cumulus oophorus--is the physiological origin of the secreted chemoattractant. METHODS: By employing a directionality-based chemotaxis assay, we examined whether media conditioned with either individual, mature (metaphase II) human oocytes or the surrounding cumulus cells attract human sperm by chemotaxis. RESULTS: We observed sperm chemotaxis to each of these media, suggesting that both the oocyte and the cumulus cells secrete sperm chemoattractants. CONCLUSIONS: These observations suggest that sperm chemoattractants are secreted not only prior to ovulation within the follicle, as earlier studies have demonstrated, but also after oocyte maturation outside the follicle, and that there are two chemoattractant origins: the mature oocyte and the surrounding cumulus cells.     

Periovulatory increase in temperature difference within the rabbit oviduct

BACKGROUND: Earlier studies demonstrated a small temperature difference between the sperm storage and fertilization sites within the oviducts of rabbits and pigs. Our aim was to reveal the time dependence of this temperature difference relative to ovulation, and to determine how this difference is generated-by temperature elevation at one of these sites or by temperature decrease at the other site. METHODS: The temperature at the sperm storage site (at the isthmus near the uterotubal junction) and at the fertilization site (the isthmic-ampullary junction) of rabbit oviducts were measured before, during, and after ovulation by two probes, connected to digital thermometers. Rectal temperature was constantly measured and served as a control for body temperature. RESULTS: The temperature difference between the fertilization site and the storage site was 0.8+/-0.2 degrees C before ovulation. This difference increased at ovulation, reaching 1.6+/-0.1 degrees C after ovulation (P<0.03). This increased difference was mainly due to temperature decrease in the sperm storage site. CONCLUSION: The temperature-difference increase within the rabbit oviduct is generated at ovulation by a reduced temperature at the sperm storage site. This temperature gradient may play a role in mammalian reproduction via sperm thermotaxis.     

Recombinant alpha2(IV)NC1 domain inhibits tumor cell-extracellular matrix interactions, induces cellular senescence, and inhibits tumor growth in vivo

Cellular interaction with the extracellular matrix is thought to be a critical event in controlling angiogenesis and tumor growth. In our previous studies, genetically distinct noncollagenous (NC) domains of type-IV collagen were shown to interact with integrin receptors expressed on the surface of endothelial cells. Moreover, these NC1 domains were shown to inhibit angiogenesis in vivo. Here, we provide evidence that a recombinant form of the alpha2(IV)NC1 domain of type-IV collagen could bind integrins alpha1beta1 and alphavbeta3 expressed on melanoma cells and inhibit tumor cell adhesion in a ligand-specific manner. Systemic administration of recombinant alpha2(IV)NC1 domain potently inhibited M21 melanoma tumor growth within full thickness human skin and exhibited a dose-dependent inhibition of tumor growth in nude mice. Interestingly, alpha2(IV)NC1 domain enhanced cellular senescence in tumor cells in vitro and in vivo. Taken together, these results suggest that recombinant alpha2(IV)NC1 domain is not only a potent anti-angiogenic reagent, but it also directly impacts tumor cell behavior. Thus, alpha2(IV)NC1 domain represents a potent inhibitor of tumor growth by impacting both endothelial and tumor cell compartments.     

The yeast VPS genes affect telomere length regulation

Eukaryotic cells invest a large proportion of their genome in maintaining telomere length homeostasis. Among the 173 non-essential yeast genes found to affect telomere length, a large proportion is involved in vacuolar traffic. When mutated, these vacuolar protein-sorting (VPS) genes lead to telomeres shorter than those observed in the wild type. Using genetic analysis, we characterized the pathway by which VPS15, VPS34, VPS22, VPS23 and VPS28 affect the telomeres. Our results indicate that these VPS genes affect telomere length through a single pathway and that this effect requires the activity of telomerase and the Ku heterodimer, but not the activity of Tel1p or Rif2p. We present models to explain the link between vacuolar traffic and telomere length homeostasis.     

Swimming exercise training prior to acute myocardial infarction attenuates left ventricular remodeling and improves left ventricular function in rats

The effect of exercise training prior to acute myocardial infarction (AMI) on left ventricular (LV) remodeling is poorly understood. This study investigated the protective effect of 3 weeks of swimming exercise training prior to AMI on cardiac morphology and function. Male Sprague-Dawley rats (n = 35) were randomly assigned to 3 groups: swimming training (n = 14, 90 min, 5 days/wk, 3 wk), sedentary (n =14), and controls (n = 7, no exercise, no MI). At the end of the training/sedentary period, rats were subjected to AMI (ExMI and SedMI) induced by surgical ligation of the left coronary artery. Thereafter, the rats remained sedentary for a 4-wk recovery period. Trans-thoracic echocardiography was performed in each group at the end of the exercise/sedentary period (pre-AMI), 24 hr after AMI, and following recovery (4 wk after AMI). No differences were observed in LV dimensions and function pre-AMI among the 3 groups; however, LV-end systolic diameter (LVESD) and LV-end systolic area (LVES-area) were significantly lower in the prior trained rats, 24 hr post-AMI with no additional change 4 wk post-AMI, during remodeling. Both LV-shortening fraction (SF%) and fractional area change (FAC%) were higher in the trained animals 4 wk post-AMI (39+/-12% vs 23+/-8%; p 0.002, and 48+/-14% vs. 38+/-9%; p 0.07, respectively). In conclusion, 3 wk of swimming exercise training prior to AMI significantly attenuated LV remodeling and improved LV function, despite no changes in LV dimensions or systolic function at the end of the exercise session. The data suggest that even a short-term training period is sufficient to induce cardiac protection.