Neurohormone activation

Neurohormonal activation plays a significant role in left ventricular remodeling and progression of heart failure. Treatment strategies that antagonize the RAS and sympathetic nervous system can attenuate the left ventricular remodeling process. Natriuretic peptides, specifically BNP, are a marker of left ventricular dysfunction. With the progressive increase in the incidence and prevalence of heart failure, treatment approaches must focus on the underlying cause as well as on blocking the neurohormonal activation that leads to the remodeling process.     

hCG and hCG subunits as tumour markers in patients with endocrine pancreatic tumours and carcinoids

Serum levels of hCG, hCG-alpha- and hCG-beta-subunits were measured in 29 patients with APUD-tumours, 16 patients with endocrine pancreatic tumours (EPT) and 13 patients with carcinoids. Twenty out of 29 patients (69%) had elevated level of hCG and its subunits. Among patients with EPT, 11 out of 16 (69%) had raised levels of these peptides. Three patients with benign tumours had normal concentrations, thus giving a frequency of 85% in the group of malignant EPT. In patients with carcinoids 9 out of 13 (69%) had elevated serum levels of at least one of the components. A discordance in secretion pattern between the two types of APUD-tumours was noticed. Only one patient, a case with a carcinoid had raised levels of the complete hCG molecule. The levels of hCG-alpha were elevated in 23% of the patients with malignant EPT and 69% of the patients with carcinoids while the corresponding frequencies of raised hCG-beta levels were 69% and 8%, respectively. Three out of 4 patients with so-called non-functioning islet cell tumours had raised levels of the subunits. These results indicate that hCG subunits are valuable tumour markers in both of these APUD-tumours, and that malignant EPT predominantly secrete hCG-beta- and carcinoids hCG-alpha-subunits.     

Effect of inhibitors of myeloperoxidase on the development of aortic atherosclerosis in an animal model

Our earlier studies have shown that some steroids increase myeloperoxidase enzyme (MPO) release from human granulocytes, and that MPO plasma levels are significantly lower in postclimacteric people. Moreover, we have proven that MPO inhibits production of atherogenic free radical superoxide anion and MPO-inhibitors increase superoxide release. The aim of the present study was to investigate the effect of MPO-inhibitors on the early phase of aortic atherosclerosis, namely the extent of intimal plaques and the thickening of the medial layer. Adult male rabbits were fed with lipid rich food (cholesterol: 1.3%, peanut oil: 8%) for 8 weeks. During this period MPO-inhibitors were also given (4-aminobenzoicacid-hydrazide/ABAH/-13.3 mg/kg/day or indometacin-5 mg/kg/day). All animals developed intimal lipid plaques (raised fatty streaks). The relative plaque-covered areas of the aortas were compared and the media thickness of the aorta was measured on plaque-free as well as plaque-containing areas. The medial smooth muscle density and peroxidase activity of the aortic media were also determined. The media thickness increased (p<0.05) in the cholesterol+ABAH as well as in the cholesterol+indometacin groups up to 375.7 (+/-60.5) and 442.5 (+/-123.4) microm, respectively, compared to the control group (cholesterol feeding alone) where it measured only 308.4 (+/-51.67) microm. The medial peroxidase activity decreased significantly in the indometacin treated group and showed a decreasing tendency using ABAH. In parallel to this there was a tendency of increase in the relative plaque covered areas. The smooth muscle density showed no significant modifications, while inhibitors of the MPO seemed to enhance aortic medial thickness, i.e. the grade of a pre-atherosclerotic lesion, in our animal model. Collectively, the anti-atherogenic effect of certain steroid hormones might be realized through the impact on MPO activity.     

Aluminium hydroxide stabilised MnFe2O4 and Fe3O4 nanoparticles as dual-modality contrasts agent for MRI and PET imaging

Magnetic nanoparticles (NPs) MnFe₂O₄ and Fe₃O₄ were stabilised by depositing an Al(OH)₃ layer via a hydrolysis process. The particles displayed excellent colloidal stability in water and a high affinity to [¹⁸F]-fluoride and bisphosphonate groups. A high radiolabeling efficiency, 97% for ¹⁸F-fluoride and 100% for ⁶⁴Cu-bisphosphonate conjugate, was achieved by simply incubating NPs with radioactivity solution at room temperature for 5 min. The properties of particles were strongly dependant on the thickness and hardness of the Al(OH)₃ layer which could in turn be controlled by the hydrolysis method. The application of these Al(OH)₃ coated magnetic NPs in molecular imaging has been further explored. The results demonstrated that these NPs are potential candidates as dual modal probes for MR and PET. In vivo PET imaging showed a slow release of ¹⁸F from NPs, but no sign of efflux of ⁶⁴Cu.     

The importance of human chorionic gonadotropin support of the corpus luteum during human gonadotropin therapy in women with anovulatory infertility

One hundred ten women with anovulatory infertility (World Health Organization [WHO] group I n = 50, WHO group II n = 60) were given 341 treatment courses with human menopausal gonadotropin (hMG) and human chorionic gonadotropin (hCG). Additional hCG was given as single or repeated injections during the luteal phase in 205 ovulatory cycles. In WHO group I, the incidence of luteal phase defects was lower and the pregnancy rate higher in cycles with extra hCG administration during the luteal phase than in cycles with no extra hCG. In WHO group II, there was no such difference after supplemental hCG. The abortion rate was the same after cycles with or without extra hCG administration. It is suggested that during ovulation induction with hMG/hCG in anovulatory women with no evidence of endogenous estrogen activity, the luteal phase should be supplemented with additional hCG.     

The role of scintigraphy in the diagnosis of mandibular bone changes

Investigating the scintigraphic images of jaws may have a diagnostic value of bone alterations of dental origin. Anterior view of whole body bone scintigraphy revealed hot spot on jaws of 61% (279) of patients. Twenty-six patients (mean age 58.3 year) from all of those who had increased tracer uptake (ITU) in the maxillo-mandibular region were called back for dental examination. 279 out of 459 (61%) patients had ITU in the maxillo-mandibular region. Dental examination revealed the dental origin of ITU in all cases. In case of periapical pathosis tracer uptake showed 28.79% increase compared to the contralateral side. In marginal periodontitis 23.82% ITU was found. In case of loading due to prosthesis 13.06% ITU was observed. The mean DMF-T value was 26.36 +/- 4.52 (D = 4.12, M = 20.8, F = 1.44). The prosthetic index was 0.42 on the mandible. The above mentioned data mean very low oral health conditions of the patients included in this examination. The results show that bone scintigraphy is a valuable procedure in detecting tooth related jaw lesions. Bone scintigraphy provides very useful data on oral health of these patients. Enrolling of these patients into regular dental care is inevitable.