CD4 T-cell cytokine correlates of diagnostic tests for latent tuberculous infection in HIV-1-infected subjects

SETTING

Public human immunodeficiency virus (HIV) clinic and tuberculosis (TB) clinics in Kampala, Uganda.

OBJECTIVE

To examine TB-specific CD4 T-cell single and polyfunctional cytokine correlates of clinical diagnostic tests for latent tuberculous infection (LTBI) in HIV-1-infected subjects.

DESIGN

Thirty antiretroviral therapy-naïve HIV-1-infected adults without active TB disease underwent clinical tuberculin skin test (TST), interferon-gamma release assay (IGRA), and in vitro flow cytometry analysis on cells stimulated with purified protein derivative (PPD) and TB antigens early secreted antigenic target 6 + culture filtrate protein 10 (EC) for frequencies of interleukin (IL) 2, IL-17, interferon-gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) expressing cells.

RESULTS

PPD-specific CD4 T-cell expression of TNF-α and IFN-γ was higher in the TST-positive than in the TST-negative group. EC-specific CD4 T-cell expression of TNF-α and IL-2 was higher in the TST+ group than in the TST- group. Expression of both PPD and EC-specific expression of IL-2, IFN-γ and TNF-α were greater in IGRA-positive than in IGRA-negative subjects. The TST+ group exhibited greater polyfunctionality than the TST- group. All cytokine combinations that contained TNF-α correlated strongly with TST size.

CONCLUSION

While IL-2, IFN-γ and TNF-α correlate with clinical tests of LTBI, TNF-α is the dominant cytokine correlating with both TST size and magnitude of IGRA response.

Improving vascular access outcomes: attributes of arteriovenous fistula cannulation success

BACKGROUND

Arteriovenous fistulas (AVFs) are the preferred access for hemodialysis (HD) yet they are underutilized. Cannulation of the fistula is a procedure requiring significant skill development and refinement and if not done well can have negative consequences for patients. The nurses' approach, attitude and skill with cannulation impacts greatly on the patient experience. Complications from miscannulation or an inability to needle fistulas can result in the increased use of central venous catheters. Some nurses remain in a state of a 'perpetual novice' resulting in a viscous cycle of negative patient consequences (bruising, pain), further influencing patients' decisions not to pursue a fistula or abandon cannulation.

METHOD

This qualitative study used organizational development theory (appreciative inquiry) and research method to determine what attributes/activities contribute to successful cannulation. This can be applied to interventions to promote change and skill development in staff members who have not advanced their proficiency. Eighteen HD nurses who self-identified with performing successful cannulation participated in audio-recorded interviews. The recordings were transcribed verbatim. The data were analyzed using content analysis.

RESULTS

Four common themes, including patient-centered care, teamwork, opportunity and skill and nurse self-awareness, represented successful fistula cannulation. Successful cannulation is more than a learned technique to correctly insert a needle, but rather represents contextual influences and interplay between the practice environment and personal attributes.

CONCLUSIONS

Practice changes based on these results may improve cannulation, decrease complications and result in better outcomes for patients. Efforts to nurture positive patient experiences around cannulation may influence patient decision-making regarding fistula use.

Pharmacologic augmentation of implant fixation in osteopenic bone

Osteoporosis presents a challenge for successful implant fixation due to an impaired healing response. Preclinical studies have consistently reported reduced osseointegration capability in trabecular bone. Although clinical studies of implant success in dentistry have not found a negative effect due to osteoporosis, low bone mass is a significant risk factor for implant migration in orthopedics. Pharmacologic treatment options that limit bone resorption or upregulate formation have been studied preclinically. While, both treatment options improve implant fixation, direct comparisons to-date have found anti-catabolic more effective than anabolic treatments for establishing implant fixation, but combination approaches are better than either treatment alone. Clinically, anti-catabolic treatments, particularly bisphosphonates have been shown to increase the longevity of implants, while limited clinical evidence on the effects of anabolic treatment exists. Preclinical experiments are needed to determine the effects of osteoporosis and subsequent treatment on the long-term maintenance of fixation and recovery after bone loss.

The validity of cognitive distance in oral and written discourse

Oral and written discourse samples of adolescents with closed head injury (CHI) and controls were analyzed to determine if efficiency and coherence measures changed as the length of their picture descriptions increased. The hypothesis was that as ideas were elaborated, the number of words used to express an idea would increase and the conceptual connectedness of ideas would decrease. This research study supported this expectation for efficiency in normal oral and written discourse but not for the discourse of participants with CHI. Further, the efficiency measure significantly differentiated the writing and speaking of the two groups as the picture descriptions were elaborated. Coherence ratings did not distinguish the development of discourse within or between groups

Oral and written discourse in adolescents with closed head injury

Analysis of oral and written discourse suggested differing cognitive demands for modes of expression. Verbal samples were provided by 8 adolescents with closed head injury (CHI) and 8 controls. A generation task using a picture stimulus was the basis for discourse. Eight measures [productivity, efficiency, semantic ties (lexical, incomplete, elliptical), maze use, coherence (global, local)] were utilized. A covariate model consisting of group membership (CHI vs control), executive functioning and working memory helps to explain variance in the discourse skills of adolescents with CHI.

Promoting compliance: the patient-provider partnership

Compliance has been defined traditionally in terms of how well a patient follows through with the recommendations of a health care provider. Patient education has often consisted of a one-way communication of provider to patient. This article advocates a multifaceted approach to compliance issues in which patients and health care providers set mutually agreed upon treatment goals. These goals must be consistent with patients' priorities and lifestyles. Patient compliance issues are examined in the context of three theoretical frameworks: (1) the Health-Belief Model, (2) Locus of Control Theory, and (3) Piaget's Theory of Cognitive Development. The insights gained from these models are then used to provide practical suggestions for enhancing compliance.

Improved patient compliance with cleft palate team regimes

A cleft palate team's prescribed regimen requires prompt and continued compliance to meet the objectives of the clinical management and to achieve the best clinical results for the patient. In a previous study (Paynter et al., 1990), we reported an overall compliance rate of 64% for patients seen by a cleft palate team during its first 8 years of operation. After the study, changes in the team's operational procedures were made in an attempt to provide better service, improve patient compliance, and improve the efficiency of the clinic. The purposes of the current clinical investigation were to determine the degree of compliance with recommendations made by the cleft palate team for the patients seen during the four years after the implementation of the changes and to identify variables that interfered with compliance. A subject was defined as the person(s) who could best respond to questions concerning the management of the team's patient. Each subject was interviewed using a questionnaire based on the Health Belief Model (Becker et al., 1977). The mean patient compliance rate was 82%. Using Jones and Caldwell's (1981) classification, 56.7% of the patients were classified as compliers, 40% as partial compliers, and 3.3% as noncompliers. Compliance with specific recommendations ranged from 58 to 100%. No specific variable was found to interfere with compliance.

A convenient human whole blood culture system for studying the regulation of tumour necrosis factor release by bacterial lipopolysaccharide

Bacterial lipopolysaccharide (LPS, endotoxin) induces a dose-dependent release of TNF in whole human blood which has been diluted five-fold. It is modulated by interferon-gamma, prostaglandin E2 and indomethacin in the same manner as observed with tumour necrosis factor (TNF) release from human monocyte/macrophage cells cultured in vitro. The whole blood culture system (WBCS) can provide up to 250 samples from 10 ml of venous blood and enables an individual blood to be assessed in terms of TNF inducibility and its modulation by other biological agents. The whole blood culture system was used to demonstrate the individual variation between blood donors. The results demonstrated that the information provided by induced cytokine release and its regulation in the ex vivo system would be a valuable addition to that obtained from in vitro methods.

A comparison of specificity and biological activity of polyclonal and monoclonal antibodies raised against Salmonella minnesota R595 lipopolysaccharide

Murine monoclonal antibodies (MAbs) and immune rabbit serum were raised against the rough mutant of Salmonella minnesota strain R595. These antibodies were tested for their ability to inhibit LPS-induced B-cell mitogenicity and neutralise LPS toxicity in chick embryos. Immune rabbit serum inhibited both mitogenicity and LPS lethality. None of the MAbs or a cocktail of antibodies were able to neutralise LPS lethality in chick embryos. However, they were able to inhibit mitogenicity by varying degrees.

Comparison of the opsonic activity of polyclonal and monoclonal antibodies raised against Salmonella minnesota strain R595

Murine monoclonal antibodies and immune rabbit serum were raised against the rough mutant Salmonella minnesota strain R595. These antibodies were tested for their opsonic activity against the homologous strain and the smooth wild type S. minnesota by luminol-dependent chemiluminescence and a microscopic assessment of phagocytosis. Immune rabbit serum opsonised both strains. Treatment with normal rabbit serum inhibited the phagocytic uptake of S. minnesota R595. None of the monoclonal antibodies RE01 (anti-KDO), RE12 (anti-KDO) and RE23 (anti-lipid A) were opsonic. Unopsonised S. minnesota R595 stimulated marked chemiluminescence possibly because of its hydrophobic surface, but this was not reflected in increased uptake by phagocytic cells. Results obtained with luminol-dependent chemiluminescence should be interpreted with caution when the opsonisation of rough bacterial strains or those with high surface hydrophobicity is being investigated.

The protein-lipopolysaccharide complex extracted with trichloracetic acid from Salmonella typhimurium effective in protection of mice against S. typhimurium infection

A protein-lipopolysaccharide complex has previously been postulated as necessary to protect susceptible mice against Salmonella typhimurium infection. Lipopolysaccharide attached to non-specific proteins, bovine serum albumin or methylated BSA, gave a specific delayed-type hypersensitivity (DTH) reaction when injected into the footpad of mice sensitized with sublethal doses of S. typhimurium. However, immunization of BALB/c mice with the complex gave no survivors after challenge with 100 LD50 S. typhimurium. Trichloracetic acid extraction of bacterial cultures produced lipopolysaccharide with attached protein. This method gave simple and convenient production of an active factor, demonstrating few major protein bands after electrophoresis. The complex elicited specific DTH reactions in sensitized mice and protected 37% of BALB/c mice against 100 LD50 S. typhimurium. Combinations of protein:lipopolysaccharide were used in DTH experiments to determine the relative importance of the components. A minimum requirement for both was demonstrated, although the ratio was not critical. Use of O-antigenic mutant strains of Salmonella indicated a role for protein in the specificity of activity of the complex.

Early haemopoietic responses to Salmonella typhimurium infection in resistant and susceptible mice

The response of colony forming cells in the bone marrow and spleen of resistant (CBA) and susceptible (C57BL) mice to Salmonella typhimurium infection was studied for 4 days after infection. The number and size of the colonies were assessed. The resistant strain exhibited an immediate response to challenge, sharply increasing the number of colonies to 2.5 times normal over 2-3 days after infection. In contrast the susceptible strain gave a slowly increased response to the same challenge, which never exceeded 1.2 times normal and fell to 0.8 times the normal. When mouse strains were immunized there was a clear distinction between the splenic and bone marrow cellularity. Immunization appeared to enhance the splenic cellularity in resistant mice but failed to in susceptible mice. In the bone marrow of susceptible mice, however, there was some evidence of an elevated response.

Protective effects of a supernatant factor from Salmonella typhimurium on Salmonella typhimurium infection of inbred mice

A supernatant factor prepared from 48-h cultures of Salmonella typhimurium has been used to immunize mice against subsequent challenge with normally lethal doses of S. typhimurium. The mouse strains used, C57BL and BALB/c, were sensitive to S. typhimurium with 50% lethal doses of less than 50 organisms. Two doses of supernatant factor, given intraperitoneally 20 days apart, protected mice against a subcutaneous challenge dose 10 days later of 100 50% lethal doses of S. typhimurium, resulting in 50 to 80% survival. The viable counts were reduced initially in organs of immunized mice compared with controls, and the multiplication of bacteria was delayed, although the final levels found in the organs would normally have been lethal. Protection obtained was specific for S. typhimurium in that no increased survival was shown after Salmonella enteritidis challenge of immunized mice. Although lipopolysaccharide was demonstrated in the supernatant factor, lipopolysaccharide alone did not protect challenged mice. Supernatant factor produced delayed-type hypersensitivity reactions in mice sensitized with nonlethal doses of Salmonella. The nature of the active factor, found to be partially protein, has yet to be elucidated.

Inhibition by low concentrations of ouabain of prolactin-induced lactogenesis in rabbit mammary-gland explants

1. Explants of mammary tissue from pseudopregnant rabbits were cultured at 37 degrees C in air for 24-48h in Medium 199 buffered with 20mm-Hepes [4-(2-hydroxyethyl)-1-piperazine-ethanesulphonic acid]. The medium contained insulin and corticosterone, or insulin, corticosterone and sheep prolactin in the presence or absence of ouabain, an inhibitor of Na(+)/K(+)-dependent adenosine triphosphatase. The responses of explants were assessed histologically, by measuring the tissue concentration of K(+), and by rates of synthesis of RNA, protein and fatty acids. The effect of ouabain on Na(+) and K(+) concentrations in slices of lactating rabbit mammary-gland tissue incubated for 1h at 37 degrees C in Krebs bicarbonate buffer was also studied. 2. Prolactin increased the concentration of K(+) in mammary explants, an effect prevented by ouabain. In slices of lactating tissue, there was a linear relationship between the log dose of ouabain (from 0.1 to 10mum) and increased Na(+) and decreased K(+) concentrations in the tissue. 3. Ouabain at concentrations up to 1mum did not affect the rate of synthesis of RNA, protein or fatty acids by explants cultured with insulin and corticosterone. By contrast, the stimulatory effect of prolactin on protein synthesis was diminished and the induction of medium-chain fatty acid synthesis by prolactin was almost abolished. RNA synthesis was unaffected. Histological examination showed no tissue damage by 1mum-ouabain. 4. Explants cultured in the presence of 2mum-ouabain for 24h retained their ability to respond to prolactin when the ouabain was removed from the culture medium. Between 24 and 48h they showed responses to prolactin of a magnitude similar to those of explants never exposed to ouabain. 5. These results show that a fully functional Na(+)/K(+)-dependent adenosine triphosphatase system is necessary for prolactin to promote secretory activity in rabbit mammary gland.

Colonoscopic polypectomy: silent perforation

The management of colon polyps has been completely revolutionized since the introduction of colonoscopic polypectomy. The reductions in patient time, cost, morbidity, and mortality are major advantages. Reported complications include primarily hemorrhage (1.7%) and frank clinical perforation (0.32%). This report describes a silent perforation after the removal of a broad based polyp through the colonscope.

Release of 14C label and complement killing of Escherichia coli

When Escherichia coli labelled with 14C were killed by complement, characteristic 14C compounds were released even when complete cell disintegration was prevented or delayed by removal of lysozyme. Treatment with heated serum only resulted in the loss of small molecular weight compounds. Separation of the products was made easier if whole serum was replaced by a salt-precipitated fraction which contained no albumin or lysozyme but retained antibody and complement. Fractionation of the bacterial products on Sephadex G-200 showed two radioactive peaks containing lipids and proteins of which a preliminary examination was made. The release of these compounds was related to complement action, since they were not found when bacteria were killed by streptomycin or ultra-violet light in the absence of complement. Nor were they found when resistant bacteria were treated with complement and survived. The possible modes of action of complement on bacterial cell walls are discussed.

Patterns of developmental deficits

Patterns of developmental deficits were studied individually in 18 children of kindergarten age. Immaturity of development impaired a variety of functions; patterns of deficits differed among children. Implications for educators concern the need for differential diagnosis, specific training, and meaningful instruction.