The expanded bed biofilter: combined nitrification, solids destruction, and removal of bacteria

Developed for tertiary nitrification, this biofilter also removed carbonaceous BOD (cBOD) and (SS). Because the biofilter is expanded, it cannot clog, and therefore does not require backflushing; yet, it removed a significant proportion of the influent SS. This unanticipated capability was due to the activities of heterotrophic bacteria, protozoa, and metazoa (nematode and oligochaete worms). The expanded bed is an intensified process, which is based on natural immobilization of microbes to small support particles. Using glassy coke as the support material, an attached layer of microbes develops, forming particulate biofilms having a superficial surface area of 1 800 m2 m(-3)(expandedbed). Autotrophic nitritifiers (Nitrosomonas spp.) were detected in the biofilm using rRNA-based molecular methods and were likely responsible, at least in part, for reducing the ammonia concentration by up to 99% (to 0.1 mg L(-1)), while the other organisms reduced cBOD and SS by up to 56% and 62%, respectively. Furthermore, the influent concentrations of Escherichia coli, coliform and heterotrophic bacteria were reduced by over 80%. It thereby provides a single process solution for combined tertiary nitrification and solids removal. Operating the process to consistently achieve < 0.5mg NH3N L(-1) and at the same time removing a significant fraction of cBOD and SS, it can replace processes such as SAFs or NTFs followed by a sandfilter.

Frequencies of HLA-A, HLA-B, HLA-DR, and HLA-DQ phenotypes in the United Arab Emirates population

The high degree of polymorphism of the human leukocyte antigen (HLA) system provides means for the study of diversity in different populations. The aim of this work is to study the HLA phenotype frequencies in the United Arab Emiratis in comparison with other geographically related Arabs, Iranians, and Asians, all living in the United Arab Emirates (UAE). Healthy blood donors and potential kidney or bone marrow donors were typed for HLA class I (n = 1880) and class II (n = 2022). Only one representative member of each family was included to avoid bias. UAE Emiratis, Arabs of Arabian Gulf Peninsula (AGP), Arabs of South Mediterranean (SMR), North African Arabs (NA), Iranians, and Asians. HLA typing was done by microlymphocytotoxicity method and/or low-resolution polymerase chain reaction-sequence-specific primer techniques. As an individual antigen, HLA-A2 had the highest frequency in all populations studied, however, the frequency of the broad antigen A19 surpassed A2 in all the groups except the AGP Arabs and Iranians. B5 was the predominant B antigen in all groups except the SMR and Asians. Amongst the class II broad antigens, DR2 was the most frequent antigen in UAE, AGP Arabs, Iranians, and Asians. The overall frequency of DQ1 was high in all groups except the SMR Arabs who had an almost equal distribution of DQ1 and DQ3. In conclusion, this study indicates that the most frequent antigens in the UAE population are HLA-A19, HLA-A2, HLA-B5, and HLA-DR2. It also sheds light on the similarities between the UAE Emiratis, AGP Arabs, Iranians, and Asians, specially the predominance of DR2 of the class II antigens.

Stem cell transplantation for patients with Fanconi anemia with low-dose cyclophosphamide and antithymocyte globulins without the use of radiation therapy

In all, 22 patients with confirmed Fanconi anemia (FA) underwent stem cell transplantation (SCT) from HLA-matched, related donors at KFSHRC. Median age at SCT was 7.6 years (range, 2.5-14.6 years). Conditioning regimen consisted of cyclophosphamide (CY) 15 mg/kg/day intravenously (i.v.) for 4 consecutive days, in addition to equine antithymocyte globulins (ATG) given i.v. at 40 mg/kg/day for four doses pre-SCT. No radiation therapy was given. For graft-versus-host disease prophylaxis, we used cyclosporin at the standard doses; ATG was added at 20 mg/kg/dose i.v. on days 2, 4, 6, 8, 10, and 12 post-SCT (total of six doses). All patients engrafted and are alive and transfusion independent with a median follow-up time of 20.2 months (range, 3.3-59 months). One patient however developed a decrease in her WBC and platelet count. Her work-up revealed slightly hypocellular bone marrow, and a series of chimerism studies over 1 year confirmed that she has stable mixed chimerism; she remains transfusion independent. We conclude that low-dose CY without radiation therapy can be used satisfactorily in the conditioning of patients with FA undergoing related SCT.

Triclosan reduces microsomal prostaglandin E synthase-1 expression in human gingival fibroblasts

OBJECTIVE

The effect of triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether) on the expression of cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1) and on the translocation of the nuclear factor-kappaB (NF-kappaB) in relation to prostaglandin E2 (PGE2) production was investigated in human gingival fibroblasts challenged with tumor necrosis factor alpha (TNFalpha).

METHODS

Fibroblasts were established from gingival biopsies obtained from six children. COX-2 mRNA and protein expression was quantified using mRNA quantitation and enzyme immunometric assay kits. mPGES-1 mRNA was analysed by RT-PCR, mPGES-1 protein and NF-kappaB translocation by immunoblotting. PGE2 was determined by radioimmunoassay.

RESULTS

The cytokine TNFalpha enhanced the expression of mRNA as well as the protein levels of both COX-2 and mPGES-1 and subsequently the production of PGE2 in gingival fibroblasts. Treatment of gingival fibroblasts with triclosan (1 microg/ml) significantly reduced the stimulatory effect of TNFalpha (10 ng/ml) on the expression of mPGES-1 at both the mRNA and the protein level by an average of 21% and 43%, respectively, and subsequently the production of PGE2 (p<0.01). Triclosan did not, however, affect the translocation of NF-kappaB or the expression of COX-2 in TNFalpha-stimulated cells.

CONCLUSION

The results show that triclosan reduces the augmented biosynthesis of PGE2 by inhibiting the mRNA and the protein expression of mPGES-1 in gingival fibroblasts. This finding may partly explain the anti-inflammatory effect of the agent previously reported in clinical studies.

Developing countries have their own characteristic problems with infection control

Infection control in developing countries differs markedly from that in the developed countries. It is important that both local and international authorities take these differences into account when formulating policies for use in developing countries. This review examines these issues and sets out some suggestions for improvements. The advantages of involving local experts in the development of such policies are emphasized.

What is the value of patient-sought second opinions?

BACKGROUND: To assess the phenomenon of second medical opinion in general internal medicine we performed a retrospective audit and descriptive analysis in a teaching hospital. METHODS: Referrals to the out-patient clinic of the University Hospital Groningen were screened using the hit 'second opinion' in the automated search program of the electronic hospital information system (ZIS). This involved the screening of the records of all patients who had visited the clinic in the period between March 1998 and July 2000. In this period 117 female and 84 male patients had visited the out-patient clinic for a second medical opinion. The case records of all these patients were analyzed for patient characteristics, chief complaint, investigations performed, referring doctor, reason(s) for referral and, if applicable, established diagnosis. Subsequently, we determined which investigations had been performed when formulating a second opinion as well as the number of times the second opinion was beneficial in terms of new diagnoses or of changes in the management plan. RESULTS: The majority (85.5%) of the patients was referred for a diagnostic problem. The chief complaints were fatigue (34.3%) and abdominal pain (26.8%). Investigations were frequently repeated at the time of the consult. A new diagnosis was established in about 10% of cases. Meanwhile, in cases of second opinions regarding further management, beneficial advice was provided in 70% of cases. CONCLUSION: A second opinion in internal medicine is most often asked for diagnostic purposes in patients with functional complaints. Despite the repetition of investigations performed, often in only a limited number of patients, a relevant new diagnosis can be established.

Uranium bioassay and radioactive dust measurements at some uranium processing sites in Egypt--health effects

The safety of radiation workers in the uranium mining industry requires close and continuous monitoring of their working conditions. In this study, external radiation surveillance, radioactive dust monitoring and the bioassay of uranium were carried out in some processing sites. As dust represents one of the most important sources of radiation exposure in mills and mines, dust monitoring and bioassays were performed for a sample of workers on the production lines. The concentration of uranium in air ranged from 22.6 x 10(-7) to 11.1 x 10(-5) Bq cm-3, and the exposure levels ranged from 1 to 80 microSv h-1. Laser fluorimetric determination of uranium in urine samples showed concentrations in the range 8.4-29.2 micrograms L-1. Renal function parameters, such as serum creatinine and urea, and hematological parameters were determined in an attempt to correlate them with radiation exposure and the health status of the workers. Urine specimens collected from workers at the ore crushing and separation site showed elevated concentrations of uranium (up to 29.2 micrograms L-1) and a strong correlation between these concentrations and the registered serum creatinine. The mean uranium excretion in the investigated group was more than 20 times the occupational exposure decision level for urine uranium of 0.8 microgram L-1.

Production of Rantes/CCL5 in human gingival fibroblasts challenged with tumor necrosis factor alpha

Chemokines are small-secreted proteins that stimulate the directional migration of leukocytes and thereby mediate the inflammatory process. The present study investigates the capacity of human gingival fibroblasts to produce the beta chemokine Rantes/CCL5. In situ hybridization, immunohistochemistry and ELISA were used to measure the induction of Rantes/CCL5 at the mRNA and protein levels, both in unstimulated gingival fibroblasts as well as in fibroblasts treated with the proinflammatory cytokines tumor necrosis factor (TNF)alpha or interleukin (IL)-1beta. TNFalpha in different concentrations (0.1-10 ng/ml) induced Rantes/CCL5 mRNA expression and protein production in 24-h cultures of human gingival fibroblasts. The expression of Rantes/CCL5-mRNA and protein production, induced by TNFalpha, was evident at 6 h and thereafter increased continuously during the study period (24 h). IL-1beta (3-300 pg/ml) also enhanced the production of Rantes/CCL5 in gingival fibroblasts. The amount of Rantes/CCL5 induced by IL-1beta (300 pg/ml), however, was less than that induced by TNFalpha (10 ng/ml). The study suggests that human gingival fibroblasts, by producing the chemokine Rantes/CCL5, participate in the regulation of the host response during the inflammatory process in the periodontal tissue.

Effect of phenytoin on the production of interleukin-6 and interleukin-8 in human gingival fibroblasts

The in vitro effect of phenytoin (PHT) on the production of interleukin-6 (IL-6) and interleukin-8 (IL-8) in human gingival fibroblasts, challenged with or without interleukin-1beta (IL-1beta), was studied. PHT (20 microg/ml) alone increased the mRNA level for both IL-6 and IL-8, as well as synergistically enhancing the production of IL-6 and IL-8, at both transcriptional and translational level in fibroblasts challenged with IL-1beta (30 pg/ml). The stimulatory effect of PHT on IL-1beta-induced IL-6 production was strongly reduced by the specific cyclooxygenase-2 inhibitor NS-398 (1 microM). The anti-inflammatory drug, dexamethasone (1 microM), abolished the production of both IL-6 and IL-8 in gingival fibroblasts challenged with PHT in the presence or absence of IL-1beta. The ability of PHT, alone as well as in combination with IL-1, to upregulate the production of IL-6 and IL-8 in human gingival fibroblasts may contribute to enhanced recruitment and activation of inflammatory cells. This effect of PHT may thereby give a prerequisite for the establishment of an interaction between cytokines and connective tissue cells in the periodontal tissue, which is suggested to lead to gingival overgrowth.

Effect of triclosan on interferon-gamma production and major histocompatibility complex class II expression in human gingival fibroblasts

BACKGROUND, AIMS

The effect of triclosan (2,4,4'-trichloro-2'-hydroxyl-diphenyl ether) on the production of interferon-gamma (IFN-gamma) and the expression of major histocompatibility complex (MHC) class II antigen was studied in human gingival fibroblasts isolated from 4 individuals.

METHODS/RESULTS

All cell lines demonstrated high IFN-gamma production in 24-h cultures of human gingival fibroblasts stimulated by phytohemagglutinin (PHA) (5 microg/ml). Human gingival fibroblasts showed a high expression of MHC class II when stimulated with 500 and 1,000 pg/ml rIFN-gamma in 7-day cultures. Treatment of the cells with triclosan (0.5 microg/ml) reduced both IFN-gamma production and MHC class II expression in human gingival fibroblast cultures. Similar inhibitory effects on IFN-gamma production and MHC class II expression were observed when the anti-inflammatory agent dexamethazone (1 microM) was used.

CONCLUSION

The present study further supports the view that the agent has an anti-inflammatory effect in addition to its antibacterial capacity.

Augmented expression of daintain/allograft inflammatory factor-1 is associated with clinical disease: dynamics of daintain/allograft inflammatory factor-1 expression in spleen, peripheral nerves and sera during experimental autoimmune neuritis

Experimental autoimmune neuritis (EAN) is an animal model of Guillain-Barré syndrome, characterized by inflammation and demyelination of the peripheral nervous system (PNS). Daintain/allograft inflammatory factor-1 (daintain/AIF-1) is a novel interferon-gamma-inducible protein expressed by macrophages during organ specific autoimmune diseases. To study the involvement of daintain/AIF-1 in EAN we induced EAN in Lewis rats by immunizing with bovine PNS myelin (BPM) and complete Freund's adjuvant (CFA). The expression of daintain/AIF-1 was examined in the spleen, peripheral nerves and sera during the course of EAN by immunohistochemistry and radioimunoassay (RIA). The expression of daintain/AIF-1 in the spleen and in the sciatic nerves peaked at the preclinical stage (day 7 post immunization (p.i.)) and at the height (day 15 p.i.) of clinical EAN, consistent with a disease promoting role for daintain/AIF-1. Daintain/AIF-1 expressing cells represented a subset of ED1+ or CD11b/c+ mononuclear cells. A significant increase of daintain/AIF-1-like immunoreactivity in sera occurred at the preclinical stage of EAN. Taken together, these data indicate that daintain/AIF-1 may play a proinflammatory role in the pathogenesis of EAN.

Altered expression of costimulatory molecules in myasthenia gravis

To characterize the involvement of costimulatory pathways in the pathogenesis of myasthenia gravis (MG), a multiparameter flow cytometry assay was adopted to enumerate blood mononuclear cells (MNC) expressing CD28, CD80, CD86, CD40, and CD40L molecules in patients with MG and healthy subjects. Patients with MG had lower percentages of CD8(+)CD28(+) cells, augmented percentages of CD4(+)CD80(+), CD4(+)CD86(+), CD8(+)CD80(+), CD8(+)CD86(+), CD14(+)CD80(+), and CD14(+)CD86(+) cells, and similar levels of cells expressing CD40 and CD40L and of B cells expressing CD80 and CD86 compared to the controls. Patients with early onset of MG (<40 years) had lower percentages of CD3(+)CD86(+), CD4(+)CD86(+), CD8(+)CD86(+) T cells and CD20(+)CD86(+) B cells compared to those with late onset (>40 years). There was a positive correlation between the patients' age and percentages of CD86(+) cells. The data indicate that the CD28/CD80-CD86 costimulatory pathway is involved in MG. The high percentages of CD80 and CD86 positive T cells and monocytes may reflect persistent activation of T and B cells, whereas the low CD28 expression may be the result of chronic exposure to CD80 and CD86. These molecules could be the focus for new and improved immunomodulating therapies of MG.

Prognostic factors for medulloblastoma

PURPOSE

To evaluate prognostic factors for medulloblastoma.

METHODS AND MATERIALS

One hundred and seventy-three consecutive patients with medulloblastoma, treated at King Faisal Specialist Hospital (KFSH) from 1988-1997, were reviewed. Eighty-four percent were children less than 15 years old. From 1988-1994, treatment was at the discretion of the investigator. From 1994-1998, patients entered a single-arm best practice protocol in which, in staged patients, the surgical intent was total resection, standard radiation treatment was defined, and adjuvant chemotherapy was given to a "high-risk" subset.

RESULTS

For 150 patients who completed surgical and radiation treatment, the 5-year survival rate was 58%, compared with 0% for 16 patients who were unable to start or complete radiation treatment. For staged patients, the 5-year survival was M0 + M1, 78% and M2 + M3, 21% (p < 0.0001). Other favorable significant prognostic factors were age >14 years and gross cystic/necrotic features in the primary tumor. The size of the primary tumor, the degree of hydrocephalus at diagnosis, the presence of residual tumor in the post-operative CT/MRI, and the functional status of the patient prior to radiation treatment were not significant factors.

CONCLUSIONS

Stage M0 + M1 was the most powerful favorable prognostic factor. In Saudi Arabia more patients present with advanced disseminated disease, 41% M2 + M3, than in the West, and this impacts adversely on overall survival. Total resection and standard radiation treatment were not sensitive prognostic factors in a treatment environment in which 78% of patients underwent at least 90% tumor resection and 60% received standard radiation treatment. In order to improve the proportion of patients able to complete radiation treatment, consideration should be given to limiting resection when the attainment of total resection is likely to be morbid, and to delaying rather than omitting radiation treatment in the patient severely compromised postoperatively.

Induction of interferon gamma in human gingival fibroblasts challenged with phytohaemagglutinin

Interferon gamma (IFN-gamma) is a potential immunoregulatory cytokine, which is secreted mainly by cells of immune origin. In this study, we examined the capacity of human gingival fibroblasts as non-professional immune cells to express IFN-gamma messenger RNA (mRNA) and to produce the protein. Cultures of fibroblast cells were established from gingival biopsies from three children. The expression of mRNA for IFN-gamma was studied by in situ hybridization, and the level of IFN-gamma was determined by cell-released capturing ELISA. Treatment of the cells with phytohaemagglutinin (PHA) (2.5, 5.0, and 10 microg/ml) increased the number of IFN-gamma mRNA expressing cells and the protein production at 1, 6, and 24 h. Non-stimulated cells did not reveal measurable levels of IFN-gamma mRNA or the protein. The inflammatory cytokines interleukin 1beta (IL-1beta) (100 microg/ml) and tumour necrosis factor alpha (TNFalpha) (10 ng/ml) did not affect IFN-gamma mRNA expression or protein production. Treatment of the cells with 1 microM phorbol 12-myristate-13-acetate (PMA) stimulated IFN-gamma mRNA expression but had no effect on IFN-gamma protein production. We conclude that human gingival fibroblasts not only transcribe IFN-gamma mRNA but also produce the IFN-gamma protein in response to PHA. The finding that human gingival fibroblasts, produce the cytokine IFN-gamma, further support the concept that these cells take an active part in the modulation of the inflammatory and immune response in the periodontal tissue.

The trouble with kidneys derived from the non heart-beating donor: a single center 10-year experience

BACKGROUND

The demand for renal transplantation has increasingly outstripped the supply of donor organs especially over the past 10 years. Although related and unrelated live donation is being promoted as one option for increasing the donor pool, it is unlikely that this will in itself be able to bridge the gap. Non-heart beating donors (NHBD) can provide an alternative supply of organs, which should substantially increase the donor pool.

METHODS

In Newcastle, NHBD kidneys have been used for transplantation for a period of 10 years. In the early period (1988-1993) excellent results were obtained (90.5% success); however, these donors were controlled NHBD, Maastricht category III. In the second phase (1994-1998) increasing numbers of donors were obtained from the Accident and Emergency Department unit. These were failed resuscitation for cardiac arrest (category II). The rates of success in this period were poor (45.5% success) and the program was halted. The third phase of the program used machine perfusion of the kidneys and glutathione S transferase enzyme analysis to assess viability.

RESULTS

Using such approaches renal transplants from largely category II donors produced a success rate of 92.3% which was significantly better than the phase II period of the program (P=0.023, Fisher two-tail test).

CONCLUSION

Machine perfusion and viability assessment of NHB kidneys in phase III of the program has increased our donor pool as well as improved the graft survival. This is particularly relevant for the use of the category II NHB donor where the incidence of primary nonfunction was high, illustrated by phase II where machine perfusion/viability assessment was not used.

Acute diverticulitis in patients 40 years of age and younger

Acute colonic diverticulitis typically occurs in patients older than 60 years of age but is uncommon in patients under the age of 40, which may lead to a delay in diagnosis. Because abdominal pain is a very common presenting symptom in emergency department patients, we retrospectively analyzed the cases of 21 patients 40 years of age and younger diagnosed with acute diverticulitis and characterized the presenting signs and symptoms, laboratory and radiographic findings, treatment, and outcome. There were 17 men and 4 women with a mean age of 34.1 +/-5.9 years. All patients had abdominal pain, with 14 (67%) patients noting pain in the left lower quadrant (LLQ) and 5 (24%) patients noting right lower quadrant (RLQ) pain. Nausea was present in 18 (86%) patients and fever in 15 (71%) patients. The mean pulse rate was 103 +/- 16 and the mean temperature was 100.7 +/- 1.4 F. Leukocytosis was present in 19 (90%) patients. Plain abdominal radiographs were obtained in 19 (91%) patients and were normal in 15 (79%) of these cases. Computed tomographic (CT) scans were obtained in 15 (71%) patients which revealed findings consistent with acute diverticulitis in 14 (93%) patients. The admitting diagnosis was diverticulitis in 10 of the 12 patients with LLQ tenderness and appendicitis in 4 of the 6 patients with RLQ tenderness. Overall, six patients were taken to surgery: three patients had cecal diverticulitis and three patients had perforated colonic diverticulitis. General treatment measures included bowel rest in 18 (86%) patients, and intravenous fluids and antibiotics in all patients. All patients survived. In conclusion, acute diverticulitis is uncommon in patients under 40 years of age; however, this condition may be confused with other conditions, usually acute appendicitis. As a result, clinicians should consider acute diverticulitis in young patients with acute abdominal pain, especially if they are male with nausea, fever, tachycardia, and leukocytosis, and consider obtaining a CT scan to aid in the diagnosis.

Elevated CD40 ligand expressing blood T-cell levels in multiple sclerosis are reversed by interferon-beta treatment

Myelin protein reactive CD4+ T cells are considered to be involved in the proposed immunopathogenesis of multiple sclerosis (MS). One particularly important molecule for T-cell activation is the CD40L (gp39) that is expressed on the surface of T cells. This study focuses on the CD40 and the CD40L expression on mononuclear cells prepared from blood from patients with MS, other neurological diseases (OND) and healthy subjects. Immunostaining followed by a three channel flow cytometry was adopted. Patients with MS had higher levels of CD3+CD40L+, CD4+CD40L+ and CD8+CD40L+ T cells compared to patients with OND and healthy subjects. Cross-sectional comparisons revealed that the elevation of CD40L+ T cell subtypes was confined to the patients with untreated MS and not observed in the patients with MS treated with interferon-beta (IFN-beta). Follow up studies showed that levels of CD3+CD40L+ and CD4+CD40L+ T cells decreased in individual patients after the initiation of the IFN-beta treatment. The enhanced expression of CD40L on CD3+, CD4+ and CD8+ T cells in patients with MS may implicate a role for this molecule in disease immunopathogenesis.

Modulation of early immune responses and suppression of Trypanosoma brucei brucei infections by surgical denervation of the spleen

OBJECTIVE

To examine critical interactions between the nervous system and the immune system during experimental African trypanosomiasis.

METHODS AND RESULTS

Inoculation of Trypanosoma brucei brucei resulted in early interferon (IFN)-gamma production, elevated corticosterone and prostaglandin E(2) (PGE(2)) levels and increased splenocyte proliferation, as measured by enzyme-linked immunospot assay, radioimmunoassay and thymidine incorporation assay, respectively. Splenic denervation suppressed IFN-gamma, corticosterone and PGE(2) production, enhanced splenocyte proliferation, and significantly reduced parasitemia and prolonged rat survival.

CONCLUSIONS

Our data show substantial effects of the nervous system on early immune responses that may influence the outcome of this disease. These effects were not dependent on cytokine inhibitory mediators such as prostaglandins or stress hormones. More investigations are required to understand the evident neural control over the immune system during infectious challenges, which may assist in novel therapeutic approaches.