Small bowel motility: relationship between smooth muscle contraction and electroenterogram signal

A study is made to correlate the electrical and mechanical activity of the smooth muscle of the small bowel. Bioelectrical signal recording from the intestinal serosa (electroenterogram) comprises a slow wave (SW) and spike burst (SB), though only the latter reflects intestinal pressure. The electroenterogram and smooth muscle pressure are simultaneously recorded in the canine small bowel. Spectral and time series analysis of the electroenterogram are performed to establish those electrical parameters that best reflect intestinal pressure. The results reveal an underlying correlation between the estimated parameters of electrical activity and smooth muscle pressure. In addition, parameters derived from the spectral techniques were closely correlated to pressure events in the intestine, even more so than the variables directly acquired from the classical time domain analyses. Specifically, spectral energy above 2 Hz and mean frequency (both calculated from the biosignal periodogram), are parameters that identify intestinal pressure. The extrapolation of these spectral parameters to long time periods could serve to define a motility index (MI) from electrical gut activity. In this context, electroenterogram recording and analysis can contribute to solve problems inherent to manometric recording, though the need for surgical intervention restricts electrical methods to experimental or surgical studies.

MUC1 and endometrial receptivity

Mucins, best known as the major constituent of mucus, are a family of highly glycosylated, high molecular weight (> or = 200 kDa) glycoproteins present on the surface of human epithelial cells. MUC1 has the features of an integral membrane protein. It has an extracellular tandem repeat domain that forms the major part of the core protein, and results in a highly repetitive structure, which is extremely immunogenic. In the protein there is also a proteolytic cleavage site reported in the proximal extracellular domain. The secreted form of MUC1 lacks the cytoplasmic tail, but it is not clear whether this results from alternative splicing or proteolysis and release of the free extracellular domain. The locus of the MUC1 gene is on band 21 of the long arm of chromosome 1 (1q21). Anti-adhesion properties of this mucin are probably the result of the unique structure of the molecule. In mouse uterine epithelium, the homologue MUC1 is regulated with reduced expression in the implantation period, but in humans, expression is high during the peri-implantation period. MUC1 may inhibit the interaction between trophoblast and apical epithelium adhesion molecules at the time of implantation, giving the possibility of forming a uterine barrier for implantation.

Thyroid abscess due to Rhodococcus equi in a patient infected with the human immunodeficiency virus

A case of thyroid abscess due to Rhodococcus equi in an HIV-positive patient with previous pulmonary abscess is reported. Rhodococcus equi is a gram-positive rod that can cause infections in both immunocompetent and immunocompromised patients, though it occurs more frequently in patients with dysfunctional cellular immune systems. Several cases of Rhodococcus equi infection in persons infected with HIV have been reported. In these patients Rhodococcus equi usually invades the lungs, producing pneumonia. These infections often relapse, accompanied by intermittent bacteremia, despite conventional treatment. Extrapulmonary abscesses can occur.

[Spontaneous peritonitis caused by ascitic fluid with Candida albicans]

Two cases are reported of spontaneous ascitic fluid Candida albicans peritonitis in two patients with liver cirrhosis secondary to HBV. In non of the two cases was there evidence of findings associated with secondary peritonitis, where ascitic fluid Candida infection has usually been reported.

Acute mediastinitis due to Rhodococcus equi in a patient with human immunodeficiency virus infection

A patient with human immunodeficiency virus infection developed anterior mediastinitis during antibiotic treatment for empyema due to Rhodococcus equi. This is the first reported case of infection with this organism in this setting. Despite an adequate course of therapy and maintenance treatment with antibiotics to which the isolate of Rhodococcus equi was susceptible in vitro, the patient experienced relapse of the infection into the mediastinum. Clinicians should consider this complication when Rhodococcus equi is present in pleural effusions.

[Community-acquired pneumonia: prospective study of 101 adult, immunocompetent patients for 1 year]

BACKGROUND

A one year prospective study was carried out to assess the etiology of community-acquired pneumonia (CAP), and also to know the incidence, characteristics and evolution of infection by Chlamydia pneumoniae; and the effectiveness of DNA probes in CAP due to Mycoplasma pneumoniae and Legionella.

METHODS

One hundred and ten patients with a diagnosis of CAP in the emergency department were studied. Serologic studies were performed, and also tests commonly used for the diagnosis of respiratory tract pathogens in respiratory samples, including serology and culture of Chlamydia pneumoniae and DNA probes for Mycoplasma pneumoniae and Legionella.

RESULTS

In 72 cases (71.3%) some pathogen was found and in 5 cases more than one microorganism was involved. The etiology was bacterial in 31% of the cases, with S. pneumoniae being the most frequent (19 cases). Forty percent of the cases were "atypical" pneumonias with 33 cases of M. pneumoniae and 5 by Chlamydia pneumoniae. Diagnostic data of viral pneumonia were found in 2 cases. DNA probes were not useful for the diagnosis of pneumonia by Legionella pneumophila and had low effectiveness (31.8%) in Mycoplasma pneumoniae CAP.

CONCLUSIONS

a) M. pneumoniae was the most frequent pathogen (33%). b) DNA probes for M. pneumoniae had low sensitivity in sputum (31.8%) and none in pharyngeal exudate. c) Acute infection by C. pneumoniae was diagnosed in 5 cases. Previous data of infection were recorded in 60.4% of the patients. d) Bacterial pneumonia (31%) was underestimated due to a low rate of bacteremic cases (7.9%) and the low number of positive cultures with definitive diagnostic value. e) The evolution was good except in two cases (death due to staphylococcal pneumonia with alcohol withdrawal syndrome and multiorganic failure by disseminated chicken-pox).

[Eikenella corrodens as a pathogen of lateral cervical abscess]

We show a case of right neck abscess, in which the Eikenella corrodens, acted as pathogen together which other microorganism. We call attention to this germ that has a slow growing in culture and generally intervene in infections in which it is assumed the presence of anaerobic germs (intrathoracic abscess, neck abscess, etc.) and the are habitually treated with clindamycin, antibiotic which Eikenella corrodens is systematically resistant (to this antibiotic).

Spontaneous bacterial peritonitis caused by Listeria monocytogenes: two case reports and literature review

Two new cases of spontaneous bacterial peritonitis (SBP) caused by Listeria monocytogenes are reported. Listeria monocytogenes was recovered from the ascitic fluid but not from the blood cultures of two adult diabetic inpatients with hepatic cirrhosis and SBP that had been treated empirically with cefotaxime. These two cases add to the 17 cases of Listeria monocytogenes SBP reported previously, stressing the relevance of this microorganism to this clinical condition. The recovery of Listeria monocytogenes from blood has been achieved in only half of the cases reported, suggesting the possibility of a direct translocation mechanism. Combinations of amino- or ureidopenicillins with beta-lactamase inhibitors or carbapenems might be more effective as empiric therapy of SBP in cirrhotic patients.

Klebsiella bacteremia: an analysis of 100 episodes

During a five-year period, 204 patients had klebsiella bacteremia at this institution; these cases constituted 6.6% of the total episodes of bacteremia. The incidence was 2.3 cases per 1,000 admitted patients. A random group of 100 cases was chosen for analysis in the present study. The disease was community acquired in 23%, nosocomially acquired in 77%, unimicrobial in 88%, or part of a polymicrobial bacteremia in 12% of episodes. Three-quarters of the episodes were caused by Klebsiella pneumoniae and the remaining one-quarter, by Klebsiella oxytoca. Portals of entry, in decreasing order of frequency, were urinary, respiratory, and biliary tracts. Twenty-four percent of the Klebsiella isolates were resistant to gentamicin. The most frequent clinical finding (in 96% of the cases) was fever. Shock occurred in 22% and pyogenic metastatic foci, in 5% of the patients. None of the patients had evidence of disseminated intravascular coagulation. Overall mortality was 25%, and factors associated with poor prognosis were inadequacy of antimicrobial chemotherapy, septic shock, type of underlying disease, and clinical condition of the patients.

Acridine orange stain in the early detection of bacteria in blood cultures

A total of 1,592 blood cultures without macroscopic signs of bacterial growth in the first 12-24 h of incubation were processed for both acridine orange stain and blind subculture. One hundred and twenty-one (7.6%) blood cultures were positive by either method; of these, 105 (8.68%) were positive by both methods, 11 (9.1%) positive by acridine orange and negative by subculture, and 5 (4.1%) negative by acridine orange and positive by subculture. The difference between the 116 blood cultures positive by acridine orange and the 110 blood cultures positive by subculture was not statistically significant (p greater than 0.1). Gram stain performed on all acridine orange positive cultures failed to reveal bacteria in 14 cases. Acridine orange staining is a sensitive, rapid and reliable method for detecting bacteria in blood cultures early during incubation. The method is inexpensive and easy to perform and can be substituted for blind subcultures.

Yersinia enterocolitica Septicemia

Human Yersinia enterocolitica septicemia is an uncommon condition. Four new cases are reported here and a review is made of 51 others taken from medical literature. Septicemia caused by this microorganism occurs more frequently in the young and in the elderly, and usually involves patients havig previous liver or blood disorders, diabetes mellitus, and other debilitating diseases. Clinically it is indistinguishable from sepsis caused by other organisms of Enterobacteriaceae, but it is important that the clinician bear its existence in mind, since Yersinia enterocolitica strains are usually resistant to beta-lactam antibiotics, whereas they are susceptible to the aminoglycosides and co-trimoxazole, among others. Susceptibilities in the blood isolates from our patients, and in another ten fecal isolates from eight other patients showed the previously described pattern. Our isolates, however, were all susceptible to the new cephalosporins, cefamandole and cefoxitin, and to the experimental ones, HR-756, T-1551, and Ly-127.935.