Research Note: Effect of synbiotic supplementation on caecal Clostridium perfringens load in broiler chickens with different necrotic enteritis challenge models.

Studies were conducted to determine the efficacy of synbiotic applications to combat the negative effects of necrotic enteritis (NE). An in vitro study was conducted to test the effect of probiotics species supernatants to decrease Clostridium perfringens (CP) proliferation. Lactobacillus reuteri, Enterococcus faecium, Bifidobacterium animalis, and Pediococcus acidilactici culture supernatants decreased the proliferation of CP at 1:1 supernatant-to-pathogen dilution in vitro. Two in vivo studies were conducted to determine the in vivo response of synbiotic supplementation containing the aforementioned probiotic strains on broiler production performance and caecal CP load in broilers induced with NE infection. In experiment 1, 75 broiler chicks were randomly allotted to 3 treatment groups, control (basal diet), ionophore (Salinomycin), and synbiotic (PoultryStar me), from day of hatch, and NE was induced in all birds. There were no significant treatment effects on BW, feed consumption, and feed gain ratio. However, at 35 D, ionophore or synbiotic supplementation increased (P < 0.05) villi height and decreased interleukin (IL)-1 mRNA abundance, while synbiotic supplementation increased (P < 0.05) IL-10 mRNA abundance compared with the control group, respectively. In experiment 2, 360 broiler chicks were randomly allotted to 3 treatments, an unchallenged negative control (control; basal diet), challenged positive control (NE; basal diet), or NE + synbiotic group (synbiotic). At both 21 and 42 D of age, NE birds had decreased (P < 0.05) BW, feed conversion, and jejunal villi height compared with control, while NE + synbiotic birds were not different from control groups. At 42 D of age, NE birds had 2.2 log/g increased CP in the ceca contents compared with control, while synbiotic birds had CP load that was not different than that of the control group. NE + synbiotic birds had significantly greater amounts of bile anti-CP IgA than the control and NE groups. It can be concluded that synbiotic supplementation decreased CP proliferation in vitro and caecal CP load in vivo while improving production parameters during an NE infection in broilers.

Time domain add-drop multiplexing scheme enhanced using a saw-tooth pulse shaper.

We experimentally demonstrate the use of saw-tooth optical pulses, which are shaped using a fiber Bragg grating, to achieve robust and high performance time-domain add-drop multiplexing in a scheme based on cross-phase (XPM) modulation in an optical fiber, with subsequent offset filtering. As compared to the use of more conventional pulse shapes, such as Gaussian pulses of a similar pulse width, the purpose-shaped saw-tooth pulses allow higher extinction ratios for the add and drop windows and significant improvements in the receiver sensitivity for the dropped and added channels.

Is celecoxib a useful adjunct in the treatment of post-tonsillectomy pain in the adult population? A randomised, double-blind, placebo-controlled study.

OBJECTIVE: To evaluate the efficacy and safety of celecoxib for pain management in post-tonsillectomy adult patients. DESIGN: A randomised, double-blind, placebo-controlled, phase 3 clinical trial was conducted in an adult population (aged 18-55 years), with a parallel group design using an allocation ratio of 1:1. METHODS: Eighty patients underwent elective tonsillectomy or adenotonsillectomy, operated on by one surgeon. They were discharged home with randomly assigned celecoxib or placebo, together with regular post-tonsillectomy medications (paracetamol and Endone). Pain scores were measured from post-operative days 1 to 10. All patients were assessed on post-operative days 5, 12 and 28. RESULTS: There were no statistically significant differences in the daily or overall pain scores, the total intake of Endone, or the time taken to achieve freedom from pain after tonsillectomy between the study arms (n = 40 each arm). The celecoxib-treated group experienced significantly more vomiting (celecoxib vs placebo p < 0.001 (Mann-Whitney test), confidence interval = 0.57 to 0.76). CONCLUSION: Celecoxib usage was associated with significantly more vomiting and did not reduce narcotic analgesia requirement post-tonsillectomy.

Dissociation of rat liver high molecular weight phosphorylase phosphatase by salt.

The chromatography of rat liver crude extract (10 000 x g supernatant) on a Biogel A-0.5 m column resulted in two peaks of phosphorylase phosphatase activity. The first peak, eluted in void volume, is of microsomal origin whereas the second peak, a cytoplasmic origin, was eluted with an apparent molecular weight of 260 000. In the presence of NaCl, the cytosolic enzyme was dissociated into intermediary (Mr = 135 000 and 68 000) and low molecular weight (Mr = 35 000) forms with an apparent activation of the enzyme activity. Similar dissociation was observed in the presence of KCl and (NH4)2SO4. A partially purified high molecular weight phosphorylase phosphatase was also dissociated into the low molecular weight form by 0.2 M NaCl. However, a protein phosphatase showing activity towards 32P-labelled histone was not dissociated by 0.2 M NaCl or 0.1 M (NH4)2SO4.

Liposomal amphotericin B (AmBisome) therapy in invasive fungal infections. Evaluation of United Kingdom compassionate use data.

BACKGROUND: Invasive fungal infections in the immunocompromised patient are associated with substantial mortality. The use of conventional amphotericin B, the main-stay of treatment, has often been limited by its adverse effects. The incorporation of amphotericin B into liposomes enables more drug to be given without an increase in adverse reactions. We examined the efficacy of AmBisome (Vestar Inc, San Diego, Calif), a small unilamellar liposomal formulation of amphotericin B, in the treatment of mycologically proven systemic fungal diseases. METHODS: A retrospective analysis of the "Compassionate Use of AmBisome" in 58 patients who were treated in 34 centers throughout the United Kingdom between July 1990 and August 1992, before licensure of the drug. RESULTS: Thirty patients had a definite or probable mycologic diagnosis, including 17 who had invasive aspergillosis, nine with Candida infections (three with mucosal disease only), three with zygomycosis, and one with cryptococcal meningitis. The overall response rate was 59% for patients with aspergillosis (80% for those who had had no prior therapy with amphotericin B) and 56% for those with candidosis. More than 40% of those in whom AmBisome was used as "salvage therapy" responded. A daily dose of up to 5 mg/kg was tolerated with minimal side effects. CONCLUSIONS: AmBisome is efficacious in the treatment of invasive fungal infections and provides an alternative therapy for those who fail to respond or become intolerant to conventional amphotericin B therapy.

Adhesion co-receptor expression and intracellular signalling in HIV disease: implications for immunotherapy.

OBJECTIVES: To investigate, in lymphocytes from HIV-1-infected individuals, the phenotypic expression of various adhesion co- or counter-receptors [lymphocyte function-associated antigen (LFA)-3, LFA-1 and intercellular adhesion molecule (ICAM)-1] involved in providing the co-stimulatory signal through the phospholipase C-gamma pathway in relation to inositol polyphosphate metabolism. DESIGN AND METHODS: Cell adhesion molecule profiles of peripheral blood lymphocytes (PBL) from 39 HIV-1-infected individuals at various stages of infection and 20 healthy laboratory controls were studied using flow cytometry. These were studied in 14 patients with late-stage disease in conjunction with their inositol polyphosphate metabolic profiles measured by high performance liquid chromatography. Levels of HIV-1 present in cell lysates were concurrently measured by a p24 antigen capture assay. In addition, the effects of a specific anti-ICAM-1 antisense oligonucleotide on the intracellular phosphatase activities of lymphocytes from a separate group of eight HIV-1-infected individuals were examined. RESULTS: The expression of LFA-1, a beta 2 integrin, was upregulated among patient PBL in parallel with disease progression, whereas that of LFA-3 (CD58) was found to be significantly reduced among the CD4+ lymphocyte subset in all stages of infection. The 5-phosphatase activity, which we previously observed to be defective in HIV disease, was found to correlate linearly with the expression of both LFA-1 and its ligand, ICAM-1. Treatment of patient lymphocytes with an antisense oligonucleotide, which reduced the cell surface expression of ICAM-1 by blocking the translation of its mRNA, resulted in further reduction of intracellular phosphatase activities. CONCLUSIONS: Our results suggest a pivotal role for adhesion co- and counter-receptors in influencing lymphocyte signalling and hence cellular response to recall antigens in HIV-1-infected individuals.

A phase III study of recombinant human interferon gamma to prevent opportunistic infections in advanced HIV disease.

The efficacy and safety of recombinant human interferon gamma (rIFN-gamma) in the reduction of opportunistic disease in patients with advanced HIV-1 infection are assessed. A 12-month double-blind, placebo-controlled, multicenter, Phase III trial of rIFN-gamma in HIV-positive patients with CD4 < 100 x 10(9)/liter on stable antiretroviral therapy. Eighty-four patients were allocated treatment on a 1:1 basis to rIFN-gamma or placebo. Patients received rIFN-gamma 0.05 mg/m(2) or 0.9% saline subcutaneously three times weekly for 48 weeks (optional extension to 18 months). The primary end point was the incidence of opportunist infections (CDC categories B/C). Secondary end points included mortality, immunological, and virological parameters. Patients on placebo had a mean of 3.45 opportunist infections (OIs) in the first 48 weeks. Patients treated with rIFN-gamma had a mean of 1.71 OIs (p = 0.04). However, the model showed overdispersion and the inclusion of a dispersion factor raised the p value to 0.13. rIFN-gamma appeared to have a particular effect on the incidence of Candida, herpes simplex, and cytomegalovirus infections. Three-year survival in the rIFN-gamma arm was 28% compared to 18% in the placebo group (not significant). rIFN-gamma-associated side-effects of headache, fatigue, rigors, influenza-like symptoms, depression, myalgia, and granulocytopenia were reversible. There was no evidence for HIV activation. Although not significant, the trend towards decreased opportunistic infections and increased survival warrants consideration of further trials of rIFN-gamma. The study gives additional information on the safety profile of this cytokine.

Camptothecin causes cell cycle perturbations within T-lymphoblastoid cells followed by dose dependent induction of apoptosis.

We have investigated the effect of the anticancer compound, camptothecin on Jurkat T-cells, a lymphoblastoid leukemic cell-line. Exposure to low concentrations led to rapid cessation of DNA (more than 95%) and RNA (more than 75%) synthesis. Perturbations to the cell cycle were observed following exposure which caused a significant accumulation of cells within G1 (P = 0.03) with a concomitant decrease in G2/M (P = 0.025). Concentrations below 0.1 microM could inhibit DNA synthesis but not induce apoptosis. Induction of apoptosis was dose dependent and could be detected as early as 3 h post exposure. The apoptotic population appeared to be derived from G1 and S-phase cells but not G2/M, coinciding with the cell cycle compartments in which DNA and RNA polymerases function. However, direct inhibition of DNA polymerase alone was not shown to be associated the induction of apoptosis or with a decrease in susceptibility to camptothecin-induced cell death. The effects of camptothecin on Jurkat T-cells and the potential mechanisms involved are discussed in the context of observations made in other transformed cell lines.

Desensitization of the inflammatory response in humans: changes in response to cardiopulmonary bypass.

Although circulating levels of interleukin 8 (IL-8), a potent pro-inflammatory chemokine, and many other inflammatory mediators increase in response to cardiopulmonary bypass, only a small proportion of patients develop a clinically significant systemic inflammatory response. The natural mechanisms that control the inflammatory response are poorly understood. To investigate the role of IL-8 in a human inflammatory model, 15 adult patients undergoing cardiopulmonary bypass for elective coronary artery bypass grafting were studied. Following reperfusion, plasma IL-8 levels increased significantly from 58 pg/mL (pre-bypass) and 66 pg/mL (after 20 min of bypass) to 98 pg/mL (p = .02 and .04, respectively), but this was accompanied by a concomitant threefold decrease in the IL-8 binding affinity of circulating neutrophils (Dissociation constant (KL) post-reperfusion/KL pre-bypass = 3.2; KL post-reperfusion/KL after 20 min of bypass = 2.8). IL-8-triggered release of myeloperoxidase and elastase by peripheral blood neutrophils ex vivo was also down-regulated following reperfusion. There were no significant changes in beta 2 integrin expression or inositol polyphosphate metabolism of peripheral blood neutrophils. These changes in receptor affinity and neutrophil responsiveness to IL-8 may represent an important in vivo regulatory mechanism which serves to prevent excessive tissue injury from inflammatory triggers.

Serodiagnosis of pericardial tuberculosis.

The AIDS epidemic has led to the resurgence of tuberculosis. Extrapulmonary manifestations may appear in over half of the patients who are dually infected. This has resulted in a rising incidence of tuberculous pericarditis in several parts of Africa such as Tanzania. We tested a solid-phase antibody competition sandwich ELISA (SACT-SE) as a potential means of diagnosing tuberculous pericarditis. Fifty-one African patients with clinically diagnosed tuberculous pericardial effusion (of whom 25 had confirmation by pericardial fluid culture) were tested using a monoclonal antibody (CDC/WHO ref. no. IT39) which was raised against a specific epitope on the Mycobacterium tuberculosis 30 kDa antigen. All but one patient had negative sputum microscopy for acid-fast bacilli. A sensitivity of 61% (at 96% specificity) was achieved. Sera from 25 African patients with smear-positive tuberculosis were also examined; of which 20 tested positive (sensitivity 80%). This is the largest study to date on the potential application of serology in diagnosing pericardial tuberculosis.

Successful diagnosis and management of cytomegalovirus carditis.

Cytomegalovirus (CMV)-associated carditis in the immunosuppressed patient carries a 60% mortality. Underlying pathogenesis is poorly understood but may involve either direct viral invasion or autoimmune cardiac damage triggered in response to the infection. Specific anti-cytomegalovirus therapy and/or anti-inflammatory drugs have been shown to benefit in cases where an early diagnosis was established. We report an unusual case of endo-pericarditis which was temporally related to acute cytomegalovirus infection diagnosed by the immediate early antigen detection in cell culture on whole blood.

A Simple and Fast Method of 3D Registration and Statistical Landmark Localization for Sparse Multi-Modal/Time-Series Neuroimages Based on Cortex Ellipse Fitting.

Existing methods of neuroimage registration typically require high quality scans and are time-consuming. We propose a simple and fast method which allows intra-patient multi-modal and time-series neuroimage registration as well as landmark identification (including commissures and superior/inferior brain landmarks) for sparse data. The method is based on elliptical approximation of the brain cortical surface in the vicinity of the midsagittal plane (MSP). Scan registration is performed by a 3D affine transformation based on parameters of the cortex elliptical fit and by aligning the MSPs. The landmarks are computed using a statistical localization method based on analysis of 53 structural scans without detectable pathology. The method is illustrated for multi-modal registration, analysis of hemorrhagic stroke time series, and ischemic stroke follow ups, as well as for localization of hardly visible or not discernible landmarks in sparse neuroimages. The method also enables a statistical localization of landmarks in sparse morphological/non-morphological images, where landmark points may be invisible.

Herniography: analysis of its role and limitations.

INTRODUCTION: Herniography is a radiographic procedure shown to be valuable in the examination of groin symptoms. It is useful in clinical situations, including the detection of occult hernia, the investigation of groin hernia when physical findings are equivocal, and the assessment of pain after inguinal hernia repair. OBJECTIVE: To systematically review the current literature on the use of herniography and to evaluate its reliability, risk, and limitations. METHOD: The Medline database was searched for publications on herniography. RESULTS: Herniography has a low false-positive rate, ranging from 0 to 18.75%. The sensitivity rate ranges from 81 to 100%, and the specificity rate ranges from 92 to 98.4%. CONCLUSION: Herniography is a safe and effective diagnostic procedure for assessing obscure groin symptoms. It has the potential of reducing the incidence of unnecessary operations. It should be considered in the evaluation of patients where the etiology of inguinal pain is unclear.

Effects of administration of alpha-tocopherol and tocotrienols on serum lipids and liver HMG CoA reductase activity.

Male hamsters were fed on semi-synthetic diets containing commercial corn oil (CO), isolated corn oil triglycerides (COTG), COTG supplemented with 30 ppm of alpha-tocopherol (COTGTL) and COTG supplemented with 81 ppm of alpha-tocopherol (COTGTH) as the dietary lipid for 45 days. Male albino guinea pigs were fed on commercial chow pellets and treated with different dosages of tocopherol and tocotrienols intra-peritoneally for 6 consecutive days. Serum and liver were taken for analysis. Our results show that stripping corn oil of its unsaponifiable components resulted in COTG which yielded lower serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) and raised high-density lipoprotein cholesterol (HDL-C) and serum triglycerides (TG) levels. These results indicate that the COTG with its fatty acids are responsible for the hypocholesterolemic effect exhibited by corn oil. However, supplementing the COTG diet with alpha-tocopherol (alpha-T) at 30 ppm significantly raised the serum TC, LDL-C and TG levels, but did not alter the HDL-C level, indicating that alpha-T is hypercholesterolemic. Supplementing the COTG diet with alpha-T at 81 ppm raised the serum TC level but to a lesser extent as compared to that obtained with 30-ppm alpha-T supplementation. The increased TC, in this case, was reflected mainly by an increased in HDL-C level as the LDL-C level was unchanged. The TG level was also raised but to a lesser extent than that obtained with a lower alpha-T supplementation. The liver HMG CoA reductase (HMGCR) activity was exhibited (56%) by the COTG as compared to CO. Supplementation of alpha-T at 30 ppm to the COTG diet resulted in further inhibition (76%) of the liver HMGCR activity. On the contrary, supplementation of alpha-T at 81 ppm to COTG diet resulted in a highly stimulatory effect (131%) on the liver HMGCR activity. Short-term studies with guinea pigs treated intra-peritoneally with alpha-T showed that at low dosage (5 mg) the HMGCR activity was inhibited by 46% whereas increasing the dosage of alpha-T to 20 mg yielded lesser inhibition (18%) as compared to that of the control. Further increase in the dosage of alpha-T to 50 mg actually resulted in 90% stimulation of the liver HMGCR activity as compared to the control. These results clearly indicate that the effect of alpha-T on HMGCR activity was dose-dependent. Treatment of the guinea pigs with 10 mg of tocotrienols (T3) resulted in 48% inhibition of the liver HMGCR activity. However, treatment with a mixture of 5 mg of alpha-T with 10 mg of T3 resulted in lesser inhibition (13%) of the liver HMGCR activity as compared to that obtained with 10 mg of T3. The above results indicate that the alpha-T is hypercholesterolemic in the hamster and its effect on liver HMGCR is dose-dependent. T3 exhibited inhibitory effect on liver HMGCR and alpha-T attenuated the inhibitory effect of T3 on liver HMGCR.

Humoral response to mycobacterial heat shock proteins in patients with constrictive pericarditis caused by tuberculosis and its implications for pathogenesis.

Tuberculous pericarditis is one of the commonest causes of cardiac failure in Transkei and the surrounding regions in southeast Africa. About 20% of patients with clinically diagnosed tuberculous pericardial effusion go on to develop pericardial fibrosis (i.e., construction), a complication which is associated with significant mortality and morbidity. The pathological mechanisms underlying this aberrant inflammatory response are poorly understood, and there is a lack of reliable pointers (clinical or laboratory) in predicting the likelihood of development of constriction. We studied the humoral response to mycobacterial heat shock proteins (65 and 71 kDa) in 25 patients with culture-positive tuberculous pericardial effusion and found a significant correlation between high anti-mycobacterial hsp60 antibody titers (before treatment) and subsequent development of fibrosis (P = 0.035 by logistic regression), which is independent of the effect of the use of prednisolone as adjuvant therapy. Possible mechanisms underlying the pathogenesis of pericardial constriction in tuberculosis are postulated.

Hydrocortisone-enhanced growth of Aspergillus spp.: implications for pathogenesis.

Aspergillus fumigatus and Aspergillus flavus are the most common cause of invasive mould infections worldwide and carry a high mortality. Corticosteroid therapy and Cushing's disease are associated with an increase in invasive aspergillosis. Corticosteroids impair immune function in mammals and, specifically, the conidicidal activity of human macrophages, which was thought to be sufficient explanation for this increased risk. However, we have found a 30-40% increase in growth rate of A. fumigatus and A. flavus exposed to pharmacological doses of hydrocortisone (a human glucocorticoid), suggesting an alternative or additional mechanism for the association. No significant effect was observed with other human steroids such as testosterone, oestradiol or progesterone, though a smaller (21%) but significant growth rate increase was obtained with the fungal sterol ergosterol. The presence of a ligand/receptor system is therefore possible in pathogenic Aspergillus spp. Although corticosterone-binding proteins have been identified in some yeast species, a demonstrable physiological effect has been lacking. Interruption of the putative ligand/receptor interaction could have a major effect on the growth and pathogenicity of A. fumigatus, providing opportunities for the development of alternative therapeutic strategies to those currently available.

Growth hormone deficiency coupled with hypogonadism in AIDS.

Both growth hormone and sex steroid deficiencies are known to affect quality of life adversely. Hypogonadism is not infrequent in patients with AIDS and due mostly to hypothalamic or end-organ failure. The prevalence of GH deficiency is unknown. We report two cases of GH deficiency in AIDS, one of which was associated with gonadotroph failure. The significance of GH deficiency in HIV infection in terms of its potential effects on disease progression is discussed. Further studies are required to assess the prevalence of GH deficiency and to clarify its role in the immunopathogenesis of AIDS.

Successful treatment of sinusitis caused by Cunninghamella bertholletiae.

Seventeen cases of infections due to Cunninghamella species have been reported worldwide in humans, and there have been only three survivors. We report a case of paranasal sinusitis due to Cunninghamella bertholletiae in an elderly patient who had diabetes mellitus and myelodysplasia. After receiving 7 weeks of therapy with deoxycholate amphotericin B (44 mg/kg or a total of 3 g) and rifampin, the patient was cured and did not have to undergo radical surgery.

The integrin-triggered rescue of T lymphocyte apoptosis is blocked in HIV-1-infected individuals.

HIV infection is associated with a disease status-dependent impairment of Ag-specific T cell responses, resulting in anergy or unchecked apoptotic cell death. beta1 integrins play an important role in the induction of T lymphocyte responses to antigenic challenge by providing a T cell costimulatory signal, and have been shown to rescue various cell types from undergoing apoptosis. We examined the integrin-triggered cell survival signal and associated pathways in CD3+ T cells derived from 69 HIV-1-infected individuals in comparison with healthy controls. We found beta1 integrin-mediated costimulation of TCR-induced T cell proliferation and protection from aberrant cell death to be absent in the majority of patients with AIDS, but intact in asymptomatic, infected individuals. The lack of integrin-mediated rescue may be partly due to an early impairment of TCR/integrin-costimulated secretion of IFN-gamma, a type 1 lymphokine that protects against TCR-induced apoptosis of T cells from HIV-seropositive donors, but not loss of integrin expression. The mechanism of integrin hyporesponsiveness appeared to correlate with a failure of the integrin-generated signal to induce pp125FAK mRNA and protein expression. Protein kinase C activation in CD3+ T cells following integrin stimulation was also impaired in HIV-infected individuals, mostly among the symptomatic/AIDS patients. Protein kinase C inactivation in T cells was shown to have a destabilizing effect in vitro on pp125FAK mRNA that contains an AUUUA motif in the 3'-untranslated region, a consensus sequence for the AU-rich elements responsible for mRNA destabilization. These aberrant changes in pp125FAK expression may have direct significance to the overall immunopathogenesis during infection with HIV-1.