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71.
Epidemiological and Environmental Investigations of Legionella pneumophila Infection in Cattle and Case Report of Fatal Pneumonia in a Calf
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Massimo Fabbi Maddalena Castellani Pastoris Eugenio Scanziani Simone Magnino Luigi Di Matteo 《Journal of clinical microbiology》1998,36(7):1942-1947
A fatal pneumonia due to Legionella pneumophila was diagnosed in a young calf reared in a dairy herd located in northern Italy. Clinical symptoms consisted of watery diarrhea, hyperthermia, anorexia, and severe dyspnea. The pathological and histological findings were very similar to those observed in human legionellosis. Legionella pneumophila serogroup 1 (SG1) and SG10 were isolated from the calf’s lung, and L. pneumophila SG1 was isolated from the calf’s liver. L. pneumophila SG1 was also demonstrated in the lung tissue by immunofluorescence and immunohistochemical examinations. Nine of 10 L. pneumophila SG1 isolates belonged to the Olda subtype, and 1 belonged to the Camperdown subtype. A very low prevalence of antibodies to Legionella was detected in cows and calves reared in the same herd. Cultures of aqueous sediment of an old electric water heater which supplied hot water for the feeding of the calves yielded L. pneumophila SG1. Four of the colonies tested belonged to the Olda subtype. Ten clinical and four environmental isolates were examined for the presence of plasmids. Nine of them were also examined by pulsed-field gel electrophoresis assay, and the same patterns were found for L. pneumophila SG1 Olda strains isolated from the calf and from the electric heater. This is the first report of a documented case of a naturally occurring Legionella pneumonia in an animal. Cattle probably act as accidental hosts for legionellae, much the same as humans. 相似文献
72.
Marruchella G Di Leonardo M Di Guardo G Romanucci M Marà M G Tiscar P Mosca F Della Salda L 《Journal of comparative pathology》2004,131(1):10-17
Heat shock proteins (HSPs), known to play a key role in cellular homeostasis, may also play a role in the defensive mechanisms of gastric mucosa. By means of appropriate immunohistochemical and immunobiochemical techniques, the expression of HSP27, HSP72 and HSP73 within the epithelium of normal and pre-ulcerative (hyperkeratinized) mucosa of the pars oesophagea of abattoir pigs was assessed. In normal mucosa, HSP72 and HSP73 expression was mainly limited to the basal epithelial cell layer, whereas HSP27 expression was consistently detected within the superficial epithelial cell layers. In hyperkeratinized mucosa, HSP72 and HSP73 immunoreactivity appeared to be more widespread, becoming very intense within epithelial cells affected by hydropic degeneration. Hyperkeratinized mucosa also showed HSP27 immunoreactivity, which was particularly intense in epithelial areas affected by hydropic degeneration. Western blot analysis confirmed HSP27, HSP72 and HSP73 expression in normal and in pre-ulcerative mucosa of the pars oesophagea. Semi-quantitative analysis showed that for all three HSPs the immunoreactivity was more intense in pre-ulcerative mucosa than in normal mucosa. The different expression patterns observed may have functional significance; further studies are needed, however, to define the role of HSPs in swine oesophagogastric lesions, the aetiology and pathogenesis of which are largely unknown. 相似文献
73.
Edwin A Bronsky Umit Yegen Ching Ming Yeh Lawrence V Larsen Giovanni Della Cioppa 《Annals of allergy, asthma & immunology》2002,89(4):407-412
BACKGROUND: Patients with exercise-induced bronchospasm (EIB) may benefit from a prophylactic beta2-adrenergic agonist that combines rapid onset with long duration of action. OBJECTIVE: To compare the protective effect against EIB of a single inhaled dose of formoterol powder delivered via the Aerolizer inhaler (Novartis Pharmaceuticals, East Hanover, NJ) with the effect of placebo and albuterol. METHODS: Eighteen patients with EIB were randomized to treatment in a double-blind, placebo-controlled, four-way, crossover study. Seventeen patients completed all four crossover periods. Each patient received in random sequence a single dose of formoterol (12 or 24 microg), albuterol (180 microg), or placebo at intervals of 5 +/- 2 days. Pulmonary function measurements were taken before and after exercise challenge tests (ECTs) at 15 minutes postdosing and at 4, 8, and 12 hours postdosing. RESULTS: Both doses of formoterol produced significantly greater protection against EIB, compared with placebo, at all timepoints (P < or = 0.016). The two doses of formoterol were not significantly different from one another at any time. Protection against EIB with albuterol was clinically significant only for the 15-minute ECT and was statistically superior to placebo for the 15-minute and 4-hour ECTs. Although formoterol and albuterol exhibited a rapid onset of action, formoterol provided longer-lasting protection over the 12-hour observation period. Rescue medication was used substantially less with either dose of formoterol, compared with albuterol or placebo. All treatments were well tolerated. Two-hour postdosing electrocardiograms and vital signs were unremarkable for all study treatments. CONCLUSION: A single dose of formoterol (12 or 24 microg) provides protection against EIB within 15 minutes of dosing and persists for up to 12 hours. Formoterol is safe and well tolerated. 相似文献
74.
Metastasis is a multistep process in which protein kinase C (PKC) appears to be significantly involved. We analysed the activity and expression of classical (, , ) and novel PKC
isoforms in B16-F1 and B16-BL6 melanoma cells maintained under different culture conditions in vitro. We used high and low concentrations of tyrosine and phenylalanine in different media (DMEM or RPMI 1640 respectively) that affect the metastatic potential and also the proliferative capacity of the cells. We also tested a weakly metastatic amelanotic B78-H1 melanoma cell line which is unaffected by the different culture conditions. In both B16 melanoma cell lines activation of PKC (without increased expression) occurred under growth conditions permissive of metastasis (DMEM). In contrast, the weakly metastatic amelanotic B78-H1 cell line showed a substantial inactivation of this isoform in the two different culture media, suggesting a specific involvement of PKC in the metastatic process. Moreover, in B16 melanoma cells, novel PKC
was activated under culture conditions which stimulated growth but not metastasis (RPMI 1640). In order to define the relationship between PKC activation and the metastatic process we also determined the release of cathepsin B. No correlation between PKC activity and cathepsin B release in either B16 melanoma cell lines could be demonstrated. 相似文献
75.
Cicinelli E Schonauer LM Galantino P Matteo MG Cassetta R Pinto V 《Human reproduction (Oxford, England)》2000,15(Z1):159-165
Endometrial transformations achieved by vaginal progesterone exceed those normally expected from the circulating concentrations obtained, this suggests some degree of direct vagina to uterus transport. We speculate on the different mechanisms involved in uterine specificity of vaginal progesterone and report data of a preliminary randomized study comparing progesterone concentrations in serum and endometrial tissue obtained from hysterectomy specimens after vaginal or i.m. administration. Eight post-menopausal women undergoing transabdominal hysterectomy were randomized to receive either vaginal progesterone gel, 90 mg, or i.m. progesterone formulation, 50 mg, at 08.00 and 20.00 on the day before surgery and at 06.00 on the day of surgery. Venous blood samples for progesterone measurement were drawn at 08.00 on the day before surgery and during the surgery. Endometrial progesterone concentrations were markedly higher in women who received vaginal progesterone (1.38+/-0.66 and 0.38+/-0.19 ng/mg protein, for vaginal and i.m. groups respectively) (P < 0.02) despite lower serum concentrations (4.17 < 0.56 and 32.32+/-11.06 ng/ml, for vaginal and i.m. groups respectively) (P < 0.001). The vaginal route induces endometrial progesterone concentrations that far exceed those expected from the serum progesterone concentrations achieved. 相似文献
76.
Riccioni G Vecchia RD Castronuovo M Di Ilio C D'Orazio N 《Annals of clinical and laboratory science》2005,35(3):285-289
Pharmacological therapy with inhaled steroids (IS) is currently considered the gold-standard of treatment for mild-persistent asthma. Leukotriene receptor antagonist drugs (LTRAs) play an important role associated with IS, allowing dose tapering and maintaining control of asthma symptoms. The aim of this study was to determine the effectiveness of montelukast (MON) to allow tapering of the inhaled dose of budesonide (BUD) in patients with mild-moderate persistent asthma. This 16-wk single-blind randomized study included 40 asthmatic patients divided in 2 treatment groups. After a run-in period (4 wk), in which all patients inhaled 400 microg of BUD twice daily (bid), group A (20 patients) received MON (oral, 10 mg/day) combined with inhaled BUD (400 microg/bid), while group B (20 patients) was treated with BUD for the whole period of the study. In both groups, at every 4 wk the dose of BUD was halved. After 12 wk of treatment the mean value of forced expiratory volume during the first sec (FEV1, as % of predicted value) was significantly greater in group A compared with group B (94 +/- 7.5 vs 83.1 +/- 6.9; p<0.005). The mean values of peak expiratory flow (PEF), the percentages of asthmatic exacerbations, and the use of beta2-short-acting agonist (SABA) were similar in the 2 groups at 4, 8, and 12 wk. In conclusion, in patients with mild-moderate persistent asthma, MON therapy is useful in tapering the dose of IS in order to reduce its side effects and to maintain the clinical stability of the disease. 相似文献
77.
78.
The complexity of RR variability is approached in the short and in the long term by means of black-box data analysis. Short term series of a few hundred beats are explored by means of informational entropy and predictability indexes. A correction to biases toward false determinism is performed assuming maximum uncertainty, whenever data do not furnish sufficient recurrences. Non-randomness and non-linearity are tested by means of surrogate data provided by random shuffling and phase randomization respectively. In the long term of the 24-h or of several hours, similar tests based on mutual information are applied and validated by means of surrogate series. In addition the state space reconstruction is carried out by means of state space non-linear filtering addressing directly the reconstructed trajectories. In this condition, parameters characterizing the hypothetical attractor, mainly the maximum Lyapunov exponent, can be reliably identified. 相似文献
79.
Specific pattern of ionic channel gene expression associated with pacemaker activity in the mouse heart 总被引:15,自引:2,他引:15
Céline Marionneau Brigitte Couette Jie Liu Huiyu Li Matteo E. Mangoni Joël Nargeot Ming Lei Denis Escande Sophie Demolombe 《The Journal of physiology》2005,562(1):223-234
Even though sequencing of the mammalian genome has led to the discovery of a large number of ionic channel genes, identification of the molecular determinants of cellular electrical properties in different regions of the heart has been rarely obtained. We developed a high-throughput approach capable of simultaneously assessing the expression pattern of ionic channel repertoires from different regions of the mouse heart. By using large-scale real-time RT-PCR, we have profiled 71 channels and related genes in the sinoatrial node (SAN), atrioventricular node (AVN), the atria (A) and ventricles (V). Hearts from 30 adult male C57BL/6 mice were microdissected and RNA was isolated from six pools of five mice each. TaqMan data were analysed using the threshold cycle ( C t ) relative quantification method. Cross-contamination of each region was checked with expression of the atrial and ventricular myosin light chains. Two-way hierarchical clustering analysis of the 71 genes successfully classified the six pools from the four distinct regions. In comparison with the A, the SAN and AVN were characterized by higher expression of Navβ1, Navβ3, Cav1.3, Cav3.1 and Cavα2δ2, and lower expression of Kv4.2, Cx40, Cx43 and Kir3.1. In addition, the SAN was characterized by higher expression of HCN1 and HCN4, and lower expression of RYR2, Kir6.2, Cavβ2 and Cavγ4. The AVN was characterized by higher expression of Nav1.1, Nav1.7, Kv1.6, Kvβ1, MinK and Cavγ7. Other gene expression profiles discriminate between the ventricular and the atrial myocardium. The present study provides the first genome-scale regional ionic channel expression profile in the mouse heart. 相似文献
80.
M C Zerbini M R Vianna D Ribeiro A A Ayoub G Porta A Sesso 《Journal of submicroscopic cytology and pathology》1991,23(1):141-145
Electron microscopic examination of an infantile hemangioendothelioma (IHE) type I of the liver, appearing in a five month old child, showed a high density of pericytes in the walls of the neoplastic vessels. These vessels, in part of the IHE patients, establish an important arteriovenous shunt leading to high output, congestive cardiac failure. It is unclear whether functions ascribed to pericytes, such as participation in microvascular contractility or as suppressors of endothelial cell proliferation are involved in two noteworthy aspects of the present case. The child exhibited no congestive heart failure and the multiple nodular lesions underwent spontaneous regression. 相似文献