Cytokine networks with infection: mycobacterial infections, leishmaniasis, human immunodeficiency virus infection, and sepsis

Distinct cytokine profiles are clearly associated with and relate to the severity of several types of infections. Cytokine networks are apparent with selected human infectious diseases, such as mycobacterial infections (leprosy, tuberculosis), the parasitic infection leishmaniasis, human immunodeficiency virus (HIV) infection, and gram-negative sepsis. Cytokine profiles are determined to some extent by two functional subsets of T lymphocytes, Th1 and Th2. The Th1 cytokines (interferon gamma, interleukin-2 [IL-2], IL-12) enhance cell-mediated immunity, inhibit humoral immunity, and result in protective effect for pathogens that are removed primarily through cell-mediated immunity (Mycobacterium tuberculosis, Mycobacterium leprae, Leishmania). The Th2 cytokines (IL-4, IL-5, IL-10, IL-13) enhance humoral immunity and inhibit cell-mediated immunity, and result in protective effect for pathogens removed primarily through humoral mechanisms. Progression of HIV infection is associated with a switch from a Th1 to a Th2 profile. For sepsis, uncontrolled activation of proinflammatory cytokines (IL-1, tumor necrosis factor-alpha, interferon-gamma) may be a fundamental defect that promotes the detrimental aspects of inflammation, whereas Th2 cytokines may be beneficial in controlling inflammation. Knowledge of basic cytokine immunopharmacology, networks, and relationships with infectious processes will aid clinicians in determining treatment approaches that are likely to be effective.     

Purulent infection and sepsis in surgical patients

The problems of pathogenesis, clinic and treatment of general purulent infection and sepsis are discussed. 1045 patients with different purulent diseases were observed by the author. Sepsis was diagnosed in 18 patients, that made 1.7 per cent to a total number of observations. Among these septic patients 8 patients died.     

Histamine release in sepsis: a prospective, controlled, clinical study

OBJECTIVE: To determine if histamine release occurs in clinical sepsis. DESIGN: Prospective, controlled, clinical study. SETTING: Interdisciplinary intensive care unit and trauma ward. PATIENTS: Sepsis was confirmed in 20 patients (test group) by the criteria of the Veterans Administration Systemic Sepsis Cooperative Study Group (1987) and was verified by positive blood culture. In addition, patients were scored by the Elebute and Stoner Sepsis Score (1983), as modified by Dionigi et al (1985). A concomitant control group consisted of 20 postoperative patients with non-life-threatening trauma to the extremities and without signs of local or systemic infection. INTERVENTIONS: Observational study. Blood samples were collected for determination of plasma histamine concentrations in both groups at the time of study entry and on five succeeding days. MEASUREMENTS AND MAIN RESULTS: The patients were well matched, and the groups were not significantly different for all criteria known to influence histamine release. Comparison of the median values of each group on days 1 through 5 demonstrated significantly higher plasma histamine values in the test group on days 1 through 4, but these values were no longer significantly higher on day 5. While none of the nonseptic control patients achieved a plasma histamine concentration of > 1 ng/mL (the concentration of which was considered to be the pathologic cutoff point representing histamine release), these values (i.e., > 1 ng/ mL) were found in nine of 20 test group patients. In the test group, nonsurvivors (n = 9) had significantly higher plasma histamine concentrations than survivors (n = 11) throughout the whole study and eight of nine nonsurvivors showed a plasma histamine concentration of > 1 ng/mL. Correlation of plasma histamine concentrations on day 1 to sepsis severity (initial Sepsis Score) showed that all but one patient with a combined low Sepsis Score (< 20 points) and histamine concentration of < 1 ng/mL survived, while all patients with a Sepsis Score of > 20 points and histamine release (plasma histamine concentration of > 1 ng/mL) died. CONCLUSION: Increased histamine concentrations were shown to be causally associated (contributory determinant) with sepsis.     

Abdominal tuberculosis: a presumptive diagnosis

BACKGROUND: Abdominal tuberculosis (TB) is common. But the diagnosis of abdominal TB is fraught with difficulties as it is often not possible to get a microbiological confirmation of the infection. We therefore undertook this study to highlight those pertinent clinical and laboratory features which would enable one to make a provisional diagnosis of abdominal TB early, to pave way for a trial of anti-tuberculosis chemotherapy. METHOD: This is a retrospective study of 12 patients treated for abdominal TB in our department over a period of 2 years. FINDINGS: Seven of the patients suffered from chronic diarrhoea for periods ranging from 4 weeks to 12 months. Four patients had progressive abdominal distension (ascites). The last patient came in with multiple abdominal swellings. Seven patients had clinical and biochemical features of malabsorption. Another 9 patients also had persistent pyrexia. The ascitic fluid was exudative in the 4 patients mentioned earlier. A definitive diagnosis could not be established in any of these patients. The diagnosis of abdominal TB was thus one of exclusion in these patients who showed prompt response to anti-tuberculosis therapy. CONCLUSION: Our study justifies a trial of anti-TB chemotherapy in TB endemic areas in the following clinical situations: (a) patients with chronic diarrhoea of unknown aetiology and (b) patients with exudative ascitic fluid, after all other possible causes, have been excluded. A prompt response to anti-TB therapy should be accepted as sufficient ground for the diagnosis of abdominal TB even when histopathological or microbiological confirmation of the disease is not possible. Our study reflects the experience of other workers from Third World countries.     

Environmental contamination due to methicillin-resistant Staphylococcus aureus: possible infection control implications

OBJECTIVE: To study the possible role of contaminated environmental surfaces as a reservoir of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals. DESIGN: A prospective culture survey of inanimate objects in the rooms of patients with MRSA. SETTING: A 200-bed university-affiliated teaching hospital. PATIENTS: Thirty-eight consecutive patients colonized or infected with MRSA. Patients represented endemic MRSA cases. RESULTS: Ninety-six (27%) of 350 surfaces sampled in the rooms of affected patients were contaminated with MRSA. When patients had MRSA in a wound or urine, 36% of surfaces were contaminated. In contrast, when MRSA was isolated from other body sites, only 6% of surfaces were contaminated (odds ratio, 8.8; 95% confidence interval, 3.7-25.5; P < .0001). Environmental contamination occurred in the rooms of 73% of infected patients and 69% of colonized patients. Frequently contaminated objects included the floor, bed linens, the patient's gown, overbed tables, and blood pressure cuffs. Sixty-five percent of nurses who had performed morning patient-care activities on patients with MRSA in a wound or urine contaminated their nursing uniforms or gowns with MRSA. Forty-two percent of personnel who had no direct contact with such patients, but had touched contaminated surfaces, contaminated their gloves with MRSA. CONCLUSIONS: We concluded that inanimate surfaces near affected patients commonly become contaminated with MRSA and that the frequency of contamination is affected by the body site at which patients are colonized or infected. That personnel may contaminate their gloves (or possibly their hands) by touching such surfaces suggests that contaminated environmental surfaces may serve as a reservoir of MRSA in hospitals.     

Powder contamination of extradural catheters and implications for infection risk

Previous papers in this supplement have addressed contamination of the peritoneal cavity by powder from the surgeon's gloves, or via airborne starch particles. This paper examines the possibility that medical devices placed inside patients may also become contaminated with powder from gloves during handling and insertion. In this way, glove powder may subsequently find its way into body cavities.     

Nativism and neurobiology: Representations, representing, and the continuum of cognition.

Whether or not the mind contains innately specified representations is highly contestable, especially in light of neurobiological evidence for the plasticity of the brain. In what follows, I provide an overview of the debate as it now stands and a discussion of the possibility, proposed by Clark (1998) and others, that representations need not be localized and are better understood as distributed systems. I then seek to tie the debate into a similar controversy surrounding the architecture of the mind. While advocates of modularity find arguments for innately specified and domain-specific representations palatable, as the thesis of innateness only strengthens their claims, favorers of a more domain-general learning mechanism are not convinced by arguments for innate specificity and instead insist that representations emerge or are learned. Rather than come down on one side of these issues, I propose, in the spirit of Cundall (2006), that cognition is more aptly conceived of as a continuum: the domains by which certain "representers" are constrained turn out to be innate, while many of the complex representations, in particular, higher-level social-cognitive representations, come from more general learning and development. Thus, the problem of reconciling nativism and neurobiology turns out to be a matter not of choosing one of two extremes, but instead, adopting an intermediary view. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neurocognitive deficits in alcoholics and social drinkers: a continuum?

Our research program has investigated neurocognitive deficits in sober alcoholics for several decades. We have shown that both male and female adult alcoholics--compared with peer nonalcoholic controls--have deficits on tests of learning, memory, abstracting, problem-solving, perceptual analysis and synthesis, speed of information processing, and efficiency. The deficits are equivalent to those found in patients with known brain dysfunction of a mild to moderate nature. Attempts to identify factors other than alcoholism to account for these differences have been unsuccessful. The deficits appear to remit slowly over 4 to 5 years. Relapse of recovering alcoholics is predicted by behavioral (e.g., depressive symptoms and neurocognitive performance) and biological measures (e.g., event-related potentials) obtained at the end of treatment. Results of recent studies support the hypothesis of a continuum of neurocognitive deficits ranging from the severe deficits found in Korsakoff patients to moderate deficits found in alcoholics and moderate to mild deficits in heavy social drinkers (more than 21 drinks/week). Individual differences in the presence and magnitude of neurocognitive deficits in social drinkers and alcoholics are hypothesized to be due, in part, to individual differences in vulnerability of the brain to alcohol or its metabolites' toxic effects.     

Controlling bacterial contamination of an enteral formula through the use of a unique closed system: contamination, enteral formulas, closed system

Contamination of enteral diets may play an essential role in formula tolerance and safety for patients. Contaminated enteral formula commonly support microbiological growth. Commercially sterile liquid formulas received from the manufacturer are required by the Food & Drug Administration (FDA) to be shelf-stable and free from enteric pathogens. This study examined the use of large volume, closed system containers in a typical nursing home. Large volume (1500 mL) containers with unique pierceable caps and piercing spikes were studied to determine their ability to reduce the incidence of microbiological contamination due to their design and ability to decrease handling requirements. This study took place in a room of a typical nursing home. In this clinical setting, 211 containers and administration spike sets were evaluated following a 36-h hangtime. Contamination was virtually nondetectable. Nursing staff in a clinical facility can effectively utilize a large volume, prefilled, ready-to-use feeding system to achieve delivery of noncontaminated product for up to 36 h hangtime.     

Training and Stroop-like interference: Evidence for a continuum of automaticity.

Three experiments varied the extent of practice in an analog of the Stroop color-word task. The experiments involved 4 phases: baseline naming of 4 familiar colors; training in consistently naming 4 novel shapes by using the names of the same 4 colors; naming the colors when they appeared in the form of the shapes; and naming the shapes when they appeared in color. In Exp 1, with up to 2 hr of training in shape naming, colors were named much faster than shapes. Interference was observed only in Phase 4. In Exp 2 (5 hr of training) shape naming sped up, but was still slower than color naming. There was symmetrical interference in Phases 3 and 4 that persisted 3 mo without further training. Exp 3 extended practice to 20 hr, by which time shape and color naming were equally rapid. After 20 hr, interference appeared only in Phase 3, reversing the original asymmetry. The overall pattern is inconsistent with a simple speed of processing account of interference. Implications of the alternative idea of a continuum of automaticity—a direct consequence of training—are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)