Influence of vasostatins, the chromogranin A-derived peptides, on the working heart of the eel (Anguilla anguilla): negative inotropy and mechanism of action

We have studied the effects of exogenous human recombinant Vasostatin-1 (VS-1), Vasostatin-2 (VS-2) and the human Chromogranin A (CGA) 7-57 synthetic peptides on the mechanical performance of the isolated and perfused working eel (Anguilla anguilla) heart. Under basal conditions, the three peptides decreased stroke volume (SV) and stroke work (SW), thus exerting negative inotropism. The VS-1-mediated negative inotropism was abolished by exposure to inhibitors of either Gi/o protein (pertussis toxin; PTx) or M1 muscarinic receptors (Pirenzepine) or calcium (Lantanum and Diltiazem) and potassium (Ba2+, 4-aminopyridine, tetraethylammonium, glibenclamide) channels, while it required an intact endocardial endothelium (EE). Using NG-monomethyl-L-arginine (L-NMMA) as an inhibitor of nitric oxide (NO) synthase (NOS), and hemoglobin as a NO scavenger, we demonstrated the obligatory role of NO signaling in mediating the vasostatin response. Pretreatment with either a specific inhibitor of soluble guanylate cyclase (GC) 1H-(1,2,4)oxadiazolo-(4,3-a)quinoxalin-1-one (ODQ), or the inhibitor of the cGMP-activated protein kinase (PKG) KT5823, abolished the VS-1-mediated inotropism, indicating the cGMP-PKG component as a crucial target of NO signaling. Of note, VS-1 was effective in counteracting the adrenergic (Isoproterenol and Phenylephrine)-mediated positive inotropism. These findings provide the first evidence that vasostatins exert cardiotropic action in fish, thus suggesting their long evolutionary history as well as their species-specific mechanisms of action.     

Immunocytochemical detection of estrogen and progesterone receptors in 124 human breast cancers

Monoclonal antibodies to human estrogen receptor (ER), and rabbit progesterone receptor (PR), also recognizing human PR, were used to detect the receptors by peroxidase immunocytochemistry in frozen sections of 124 primary breast carcinomas. Both ER and PR were almost exclusively located in carcinoma cell nuclei, with heterogeneous distribution and intensity. The staining results were evaluated semiquantitatively (histoscore), based on the percentage of positively stained carcinoma cells and nuclear staining intensity. The receptor status thus determined was as follows: ER+PR+ in 50 patients, ER+PR- in 23, ER-PR- in 26, and ER-PR+ in 3 patients. There was a 79% (ER) or 70% (PR) agreement in the positivity/negativity between the immunocytochemical and steroid-binding assay (in 102 patients) with a highly significant correlation. The histoscore values increased significantly with cytosol receptor levels (ER, r = 0.623, P less than 0.001; PR, r = 0.366, P less than 0.01).     

Imprint cytology in immunocytochemical analysis of oestrogen and progesterone receptors of breast carcinoma.

Cytological imprint material from 26 mammary carcinomas was stained with monoclonal antibodies to oestrogen and progesterone receptors in an immunoperoxidase procedure. The staining result was compared with that of parallel stainings of frozen tissue sections of the same tumours. The peroxidase reactions in both techniques were semiquantitatively assessed (histoscore). In both sets of stainings the results agreed in 25 of 26 cases (oestrogen receptor: 19 positive, six negative; progesterone receptor: 14 positive, 11 negative). The histoscores of imprint preparations and cryostat sections showed a significant correlation in linear regression analysis (oestrogen receptor: r = 0.755, p less than 0.001; progesterone receptor: r = 0.740, p less than 0.001). Imprint cytology is simple, does not require expensive instruments, and no separate specimen has to be sequestered. It is especially suitable for immunocytochemical steroid receptor analysis of small breast carcinomas.     

Alterations in the insulin-like growth factor system during the menstrual cycle in normal women

Objectives: To evaluate the effects of endogenous estrogens and progestins on the IGF-system during the normal menstrual cycle in healthy premenopausal women not using contraceptive drugs. Methods: Nine women had fasting blood samples obtained at 2–3 days intervals during a 5 week study period. Plasma levels of IGF-I, IGF-II, IGFBP-1, IGFBP-3, estradiol and progesterone were measured by radioimmunoassay (RIA) in each sample. IGFBP-3 was also evaluated by Western ligand blot (WLB) and immunoblot. Any differences between the menstrual phase (defined as day 1–5), follicular and luteal phases (separation based on plasma estradiol and progesterone values) were evaluated by the Friedman test. Results: A small but significant difference in plasma levels of IGF-I (P<0.01) and IGFBP-3 (P<0.05) measured by RIA between the three phases were seen with the highest levels found during the follicular phase. No change in plasma levels of IGFBP-1 and IGF-II was found and immunoblots did not reveal any alteration in the ratio of fragmented to intact IGFBP-3 during the menstrual cycle. A positive correlation between plasma levels of IGF-I and estradiol was seen in 8 out of 9 patients (P=0.012). Conclusions: The finding of a slight but significant higher level of plasma IGF-I in the follicular and luteal phases compared with the menstrual phase suggests plasma estradiol may influence the level of this growth factor. This hypothesis is further supported by the finding of a correlation between plasma levels of IGF-I and estradiol but not progesterone in individual patients at different times during the menstrual cycle.     

Comparison of two urinary antigen tests for establishment of pneumococcal etiology of adult community-acquired pneumonia

The Binax NOW immunochromatographic test (ICT) detecting the pneumococcal C polysaccharide and a serotype-specific latex agglutination (LA) test detecting 23 pneumococcal capsular antigens were evaluated for establishing pneumococcal etiology in community-acquired pneumonia (CAP) by use of nonconcentrated urine. ICT was considered to be strongly positive for result lines at least as intense as the control line and weakly positive for less intense result lines. When 215 adult CAP patients were tested, strong ICT, weak ICT, and LA positivity were found in 28, 24, and 16 patients, respectively; of these patients, 13 (46%), 6 (25%), and 13 (81%), respectively, had pneumococcal bacteremia and 27 (96%), 17 (71%), and 15 (94%), respectively, had Streptococcus pneumoniae isolated from blood, sputum, and/or nasopharynx. Among 108 controls tested, 2 (1.9%) were weakly ICT positive. When weak positivity was considered negative, the sensitivity of ICT decreased from 79% (19 of 24) to 54% (13 of 24), while the specificity increased from 83% (158 of 191) to 92% (176 of 191); no controls were false positive. The sensitivity and specificity of LA were 54% (13 of 24) and 98% (188 of 191), respectively. Eight of nine LA serotypes corresponded to culture serotypes. In conclusion, using nonconcentrated urine and dividing ICT-positive results into strongly and weakly positive results is a suitable way of performing ICT. While weak ICT positivity should be interpreted with caution, strong ICT positivity and LA positivity should be considered supportive of pneumococcal etiology in adult CAP. As such, these assays might have implications for antibiotic use in CAP. LA has promising potential for pneumococcal serotyping, although further evaluation is required.     

Utilization of Acetate in the Human Forearm during Exercise after Ethanol Ingestion

The uptake of acetate in the human forearm was studied in five fasting (14 h) subjects during 10-min periods of ergometer work at 7 and 10 kilopond-meters per minute (kpm/min). A constant arterial acetate concentration was established by administration of a small quantity of alcohol (25 g) to the subjects after a control work period. Blood flow was measured by an indicator dilution technique. Acetate uptake varied linearly with the product of arterial acetate concentration and blood flow. Acetate metabolism was calculated to account for about 6.5% of the energy metabolism, assuming complete combustion to carbon dioxide and water. Oxygen uptake and blood flow did not change in the presence of acetate and ethanol.After administration of ethanol the arterial concentrations of FFA and glycerol decreased to about half, whereas the lactate concentration increased to about twice the control values, confirming other reports.Glucose utilization was increased and lactate output decreased during the ethanol periods, presumably a consequence of the changing arterial concentrations and increased insulin level. Measurements of the arterial and venous lactate/pyruvate concentration ratios indicate that the NAD-mediated cytoplasmic redox state in the muscle is not changed in the presence of acetate and ethanol.     

Effect of the serotonin agonist buspirone on behaviour and hypothalamic-pituitary-adrenal axis in confident and fearful mink

Behavioural and hypothalamic-pituitary-adrenal (HPA) axis responses were investigated in farm mink (Mustela vison) selected for either confident or fearful behaviour for nine generations.Two groups of 2-year-old confident (n=12) and fearful (n=12) female mink were given the serotonin (5-HT) 1A receptor agonist buspirone (1.25 mg/kg/day), whereas two other groups of 2-year-old confident (n=12) and fearful (n=12) female mink were given saline, continuously for 5 weeks via osmotic minipumps. Behavioural reactions towards a novel object and towards humans were tested after 19-25 days, and HPA axis reactivity [adrenocorticotropic hormone (ACTH), cortisol] was measured after 28-31 days of treatment. Confident mink were more exploratory than fearful mink towards humans and a novel object. Confident mink spent more time in contact with the object than did fearful mink during saline-but not during buspirone-treatment. buspirone increased approach-withdrawal conflict behaviour towards a object in fearful mink only. The chronic dose of buspirone did not reduce fear towards humans and did not affect latencies to reaction, number of contacts, number and duration of manipulations, and stereotypic behaviour in a Novel Object test. Different HPA axis responses have emerged between confident and fearful mink, together with a different degree of fear-related behaviour. Fearful mink have a higher cortisol combined with a lower ACTH secretion than confident mink in response to capture and blood sampling. The central serotonergic system may be involved, and even though the precise underlying mechanisms are presently unknown, treatment with a 5-HT(1A) receptor agonist reduces the difference between confident and fearful mink in HPA axis reactivity.     

Lack of alpha-1 integrin alters lesion morphology during pulmonary Mycobacterium tuberculosis infection

The hallmark of Mycobacterium tuberculosis infection is the granuloma, a highly dynamic immune structure that contains the bacilli during chronic infection. Here, we examined if alpha1beta1 integrin is required in the development and maintenance of the granulomatous structure during pulmonary infection using the alpha1 integrin knockout (alpha1-null) mouse. The alpha1beta1 integrin is expressed on activated macrophages and T cells, and interacts with collagen molecules in the extracellular matrix (ECM), and thus may play a role in the granulomatous process. Following pulmonary infection with virulent M. tuberculosis, lungs of alpha1-null infected mice had striking differences in granuloma structure, as well as distinct and markedly thickened alveolar septae. By day 180, there were regions of cell death within granulomatous lesions, characterized by cellular debris in these mice. To determine if this molecule was necessary for T cell trafficking within the lungs, the expression of CD4, CD44 and CD62L was monitored. The number of activated and IFN-gamma-producing CD4(+) T cells increased in the lungs of alpha1-null mice during the chronic phase of infection, although they had decreased concentrations of TNF-alpha and MMP-9. These results suggest that while alpha1beta1 integrin is not required for trafficking or maintenance of T cells in M. tuberculosis infected lungs, it does play a role in granuloma structure and integrity during the chronic phase of infection.     

Rapid Selection of Plasmodium falciparum Chloroquine Resistance Transporter Gene and Multidrug Resistance Gene-1 Haplotypes Associated with Past Chloroquine and Present Artemether-Lumefantrine Use in Inhambane District,Southern Mozambique

Chloroquine (CQ) use in Mozambique was stopped in 2002 and artemether-lumefantrine (AL) was implemented in 2008. In light of no use of CQ and extensive use of AL, we determined the frequency of molecular markers of Plasmodium falciparum drug resistance/tolerance to CQ and AL in persons living in Linga-Linga, an isolated peninsula and in Furvela village, which is located 8 km inland. The P. falciparum chloroquine resistance transporter gene CVMNK wild type increased in frequency from 43.9% in 2009 to 66.4% in 2010 (P ≤ 0.001), and combined P. falciparum multidrug resistance gene 1 N86-184F-D1246 haplotype increased significantly between years (P = 0.039). The combination of P. falciparum chloroquine resistance transporter gene CVMNK and P. falciparum multidrug resistance gene NFD increased from 24.3% (2009) to 45.3% in (2010, P = 0.017). The rapid changes observed may largely be caused by decreased use of CQ and large-scale use of AL. In the absence of a clear AL-resistance marker and the (almost) continent-wide use of AL in sub-Saharan Africa, and when considering CQ reintroduction, continued monitoring of these markers is needed.     

WEILBY-BURTON ARTHROPLASTY OF THE TRAPEZIOMETACARPAL JOINT OF THE THUMB

Twenty-three patients (25 thumbs) were treated by tendon interposition arthroplasty for trapeziometacarpal arthrosis as described by Weilby and modified slightly as described by Burton and Pellegrini. There was good (4/25, 16%) or complete (19/25, 76%) pain relief in 23 (92%) of the cases. Activities of daily living were generally easier. Mobility and strength of the thumb were satisfactory. One patient had signs of instability during a stress test. We conclude that our technique produces a stable and pain-free thumb joint. However, careful selection of the patients for this procedure is essential, and the patient must be given comprehensive information about all stages.