The effect of osmotic stress on the production of nukacin ISK-1 from Staphylococcus warneri ISK-1

The effects of several additives on the production of a lantibiotic, nukacin ISK-1, from Staphylococcus warneri ISK-1, in batch fermentation were studied. NaCl, KCl and sorbitol stimulated nukacin ISK-1 production. The addition of 1.4 M NaCl increased nukacin ISK-1 activity 1.5-fold over the control, while cell growth and glucose consumption were inhibited. Nukacin ISK-1 production increased with increasing osmolarity of the medium up to about 3 osmol/kg; however, further increases in osmolarity diminished productivity, irrespective of the kind of additive. Northern blot analysis showed that transcription of the nukacin ISK-1 structural gene (nukA) was activated in the presence of 1.4 M NaC1. These data indicate that the stimulation effect was due to osmotic stress, which acted, at least in part, at the transcriptional level on the nukA gene.

Severe vulvovaginitis associated with intravaginal nystatin therapy

A 64-year-old woman had severe vulvovaginitis develop while she was receiving intravaginal nystatin therapy for Candida glabrata infection. Mucocutaneous adverse effects have rarely been reported with nystatin despite long years of use. This complication should be included in the differential diagnosis of clinical failure of intravaginal nystatin therapy.

Crossover assessment of serum bactericidal activity of grepafloxacin, ofloxacin and clarithromycin against respiratory pathogens after oral administration to healthy volunteers

Serum bactericidal activity was studied in a crossover manner in 10 volunteers, after 2-day administration of grepafloxacin 600 mg qd, ofloxacin 400 mg bid and clarithromycin 500 mg bid. Bactericidal activity against clinical isolates of Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Klebsiella pneumoniae, was estimated using a standardized microdilution method. Grepafloxacin was highly active against Gram-negative organisms and adequate against pneumococci (mean, 1:13.3). Clarithromycin was very active against both penicillin-susceptible and penicillin-partially-resistant S. pneumoniae (1:102.5) but had poor activity against H. influenzae (1:3.1). Minor adverse effects were commonly associated with grepafloxacin.

In vitro susceptibility of recent clinical isolates of Chlamydia trachomatis to macrolides and tetracyclines

We tested the in vitro activity of clarithromycin, azithromycin, roxithromycin, erythromycin, doxycycline, and tetracycline against 50 clinical isolates of Chlamydia trachomatis. The minimal inhibitory concentrations (MICs) and the minimal bactericidal concentrations (MBCs) were determined in a tissue culture system using cycloheximide treated McCoy cells. MIC values for all the isolates were < or =0.015 microg/ml for clarithromycin, < or =0.125 microg/ml for roxithromycin and azithromycin, and < or =0.25 microg/ml for erythromycin and doxycycline. Almost half of the isolates (44%) were inhibited only by a concentration of 0.5 microg/ml of tetracycline. MBC as high as 4 microg/ml was displayed by doxycycline and tetracycline against 8% and 4% of the isolates respectively of the agents recommended by the Center for Disease Control as drugs of choice for the treatment of chlamydial infections, azithromycin exhibited a markedly better in-vitro activity than did erythromycin and doxycycline.

Immunotherapy for recurrent colorectal cancers with human monoclonal antibody SK-1

BACKGROUND

The human monoclonal antibody SK-1 recognizes a glycoprotein expressed on the majority of colon cancer tissues. In the current study, we evaluated the safety, toxicity and preliminary efficacy of escalating dosages of SK-1 in patients with advanced colon cancer.

PATIENTS AND METHODS

SK-1 was administered intravenously at 2, 4 or 10 mg three times to three groups of patients with recurrent colon cancer. The clinical outcome and the induction of serum anti-idiotypic antibody (Ab2) were assessed periodically.

RESULTS

The mean rate of serum CEA level increase declined significantly during the eight weeks following the treatment. In four patients, serum titer of anti-idiotypic IgG antibodies to SK-1 (Ab2) continued to increase following the treatment.

CONCLUSION

HuMAb SK-1 was well-tolerated and can be safely administered. It was suggested that SK-1 natural antibody not only possessed direct cytostatic activity against colon carcinoma, but may also have induced carcinoma-related, anti-idiotypic antibody responses.

Adsorption in sepsis

The pathophysiology of sepsis offers a highly complicated scenario. In sepsis, endotoxin or other gram-positive-derived products induce a complex and dynamic cellular response, giving rise to several mediators known to be relevant in the pathogenesis of septic shock such as specific mediators, substances responsible for up- or down-regulation of cytokine receptors and cytokine antagonists, inactivators of translational or transductional pathways, and precursor molecules. In this review, we delve into some new concepts stemming up from the use of sorbents in continuous plasma filtration. Nonspecific simultaneous removal of several mediators of the inflammatory cascade have led to improved outcomes in animal models of septic shock and to improved hemodynamics in a pilot clinical study. It seems of great importance to explore all possible treatment techniques that may have a direct impact on circulating mediators of sepsis and that also may interfere with the imbalance between proinflammatory and anti-inflammatory substances in the critically ill patient with multiple organ failure. In this view, the application of sorbents appears to open new and interesting therapeutic options. The search for innovative treatments specifically targeted to the special needs of the critically ill patients seems therefore more important than the attempt to adjust concepts and technologies that are normally applied to patients with chronic renal failure.

Effects of different doses in continuous veno-venous haemofiltration on outcomes of acute renal failure: a prospective randomised trial

BACKGROUND

Continuous veno-venous haemofiltration is increasingly used to treat acute renal failure in critically ill patients, but a clear definition of an adequate treatment dose has not been established. We undertook a prospective randomised study of the impact different ultrafiltration doses in continuous renal replacement therapy on survival.

METHODS

We enrolled 425 patients, with a mean age of 61 years, in intensive care who had acute renal failure. Patients were randomly assigned ultrafiltration at 20 mL h(-1) kg(-1) (group 1, n=146), 35 mL h(-1) kg(-1) (group 2, n=139), or 45 mL h(-1) kg(-1) (group 3, n=140). The primary endpoint was survival at 15 days after stopping haemofiltration. We also assessed recovery of renal function and frequency of complications during treatment. Analysis was by intention to treat.

RESULTS

Survival in group 1 was significantly lower than in groups 2 (p=0.0007) and 3 (p=0.0013). Survival in groups 2 and 3 did not differ significantly (p=0.87). Adjustment for possible confounding factors did not change the pattern of differences among the groups. Survivors in all groups had lower concentrations of blood urea nitrogen before continuous haemofiltration was started than non-survivors. 95%, 92%, and 90% of survivors in groups 1, 2, and 3, respectively, had full recovery of renal function. The frequency of complications was similarly low in all groups.

INTERPRETATION

Mortality among these critically ill patients was high, but increase in the rate of ultrafiltration improved survival significantly. We recommend that ultrafiltration should be prescribed according to patient's bodyweight and should reach at least 35 mL h(-1) kg(-1).

Role of alcohol dehydrogenase E (ADHE) in the energy metabolism of Giardia lamblia

Two hammerhead ribozymes flanked by Giardia lamblia alcohol dehydrogenase E (ADHE) antisense RNA fragments, ARzS and ARzL, were designed, synthesized and found capable of cleaving an ADHE mRNA fragment at the anticipated position in vitro. The ribozymes were then electroporated into Giardia trophozoites and expressed via the giardiavirus-mediated RNA expression system. Expression of the ribozyme with two short antisense arms, ARzS, was stabilized under puromycin selection and demonstrated a 33% reduction in ADHE mRNA and 25% decrease in NAD+-dependent ADH activity in the transfectants. Expression of ARzL, the ribozyme with two long antisense arms, cannot be enriched under puromycin without killing the transfected cells, probably due to excessive depletion of ADHE. Without the drug selection, however, transient expression of ARzL 20-40 h after electroporation resulted in an 83.7% loss of ADHE mRNA and an 84.5% reduction in ADH activity in the transfected cells. When the ribozyme moiety was removed from ARzL, the latter retained some of its in vivo activity of lowering ADHE mRNA and ADH activity, suggesting that inhibition of ADHE gene expression in Giardia can be accomplished by the antisense RNA alone, albeit less efficiently. The ADHE deficient transfectant demonstrated relatively poorer anaerobic growth but grew more vigorously than the wild type under aerobic conditions, suggesting that the role of ADHE in providing NAD+ through anaerobic reduction of acetyl-CoA to ethanol could be replaced by a yet unidentified aerobic enzyme(s) in Giardia. The close association consistently observed between the levels of ADHE mRNA and ADH activity in transfected Giardia cells suggests that ADHE could be the only functional alcohol dehydrogenase in Giaradia. One other Giardia gene encoding a putative Class III ADH, GIADH3, was identified and cloned, but no Class III ADH activity could be detected in Giardia by the conventional enzyme assays. This gene is thus probably unexpressed in Giardia trophozoite.

Inhibition of pyruvate-ferredoxin oxidoreductase gene expression in Giardia lamblia by a virus-mediated hammerhead ribozyme

Giardia lamblia is a primitive eukaryotic microorganism that derives its metabolic energy primarily from anaerobic glycolysis. In trophozoites, pyruvate-ferredoxin oxidoreductase (PFOR) converts pyruvate to acetyl-CoA with the transfer of a pair of electrons to ferredoxin, which can then reduce metronidazole and activate it into a potent antigiardiasis agent. It is unclear, however, whether this anaerobic disposal of electrons is essential for the energy metabolism in Giardia. In the present study, cDNAs encoding hammerhead ribozyme flanked with various lengths of antisense PFOR RNA were cloned into a viral vector pC631pac derived from the genome of giardiavirus (GLV). RNA transcripts of the plasmids showed high cleavage activities on PFOR mRNA in vitro. They were introduced into GLV-infected G. lamblia trophozoites by electroporation and stablized in the transfected cells via serial passages under puromycin selection. PFOR mRNA and enzyme activity in the transfected cells were decreased by 46-60% with the ribozyme PRzS flanked with 20 nt PFOR antisense RNA on each arm and by 69-80% with the ribozyme PRzL flanked with 600 and 1500 nt PFOR antisense RNA. PRzS without the inserted ribozyme or ribozyme flanked with alcohol dehydrogenase E antisense RNA showed no effect on PFOR mRNA and activity. The ribozyme-transfected cells demonstrated significantly enhanced resistance to metronidazole and grew equally well under anaerobic and aerobic conditions. In contrast, the wild-type cells grew slightly better anaerobically than the transfectants but did not grow at all in aerobic conditions. Thus, the reduced PFOR expression enables Giardia to grow under molecular oxygen and the presence of PFOR enhances the anaerobic growth of Giardia with an increased susceptibility towards metronidazole. In addition, this study demonstrated for the first time the feasibility of using a viral RNA vector to express a ribozyme targeted at a specific mRNA in G. lamblia to reduce the expression of a specific gene.

Bioethical issues related to continuous renal replacement therapy in intensive care patients

OBJECTIVE

To examine the ethical approach of intensivists and nephrologists to continuous renal replacement therapy (CRRT).

DESIGN

A questionnaire.

SETTING

The First International Course on Critical Care Nephrology.

PARTICIPANTS

The participants in the course (around 500).

RESULTS

Most participants think that establishing ethical criteria for managing CRRT is a medical task, as clinicians have adequate criteria for defining futility. However, many responders would grant the request of starting futile CRRT or would maintain it if requested by the family. Only 55% believe that informed consent is necessary for initiating CRRT; one out of four would start or maintain unwanted life-saving CRRT. In case of lack of equipment, the majority would select the patients, excluding the worst one or on a "first-come, first-served" basis. Withholding and withdrawing are regarded differently by most responders. Again, most think that every vital support should be withdrawn when futile, but practical and psychological aspects still influence the final decision. Responders think that ethics critical care committees can help in the management of ethical problems in ICU.

CONCLUSIONS

Our results show that several ethical questions are still unsolved and that practical and psychological aspects of the treatment process can be stronger than bioethical principles.

Dependence of single-bubble sonoluminescence on ambient pressure

Kondic et al.'s theory makes several specific predictions on the dependence of single-bubble sonoluminescence (SBSL) on ambient pressure. We have carried out experiments to verify these predictions for air bubbles in a water-glycerine mixture at about 17.5 kHz. The results show an increase in SBSL with reduced ambient pressure down to a critical value below which SBSL is extinguished. The results are all in good agreement with Kondic et al.'s theory and are also compatible with the dissociation hypothesis of Lohse et al.

Phase II trial of bryostatin 1 in patients with relapsed low-grade non-Hodgkin's lymphoma and chronic lymphocytic leukemia

Bryostatin 1 is a natural product isolated from the marine bryozoan Bugula neritina in 1982 and is currently undergoing evaluation in a number of malignancies. Twenty-five patients with relapsed, low-grade non-Hodgkin's lymphoma or chronic lyphocytic leukemia (CLL) received bryostatin 1 by 72-h continuous infusion every 2 weeks at a dose of 120 microg/m2 per course. Patients who progressed while receiving bryostatin 1 alone could participate in a feasibility study by receiving vincristine administered by bolus i.v. injection immediately after the completion of the bryostatin 1 infusion. The dose of vincristine was escalated in groups of three patients as follows: level 1, 0.5 mg/m2; level 2, 1.0 mg/m2; and level 3, 1.4 mg/m2 with vincristine doses capped at 2.0 mg for all patients. Bryostatin 1 alone resulted in one complete remission and two partial remissions. Nine patients received sequential treatment with bryostatin 1 and vincristine. The addition of vincristine at a dose of 2 mg was feasible and caused the expected dose-related sensory neuropathy. Phenotypic analysis by flow cytometric analysis on pre- and post-bryostatin 1-treated peripheral blood lymphocytes revealed up-regulation in the coexpression of CD11c/ CD22 on CD20+ B cells in two of four CLL patients studied, which is consistent with in vitro findings of differentiation of CLL cells to a hairy cell phenotype.

Pseudomembranous colitis: report of a severe case with unusual clinical signs in a young nurse

We describe the case of a young and otherwise healthy nurse who developed pseudomembranous colitis ten days after receiving oral clindamycin for dental infection. Her clinical course was particularly stormy and was characterized by severe diarrhea and vomiting, profuse ascites, pleural effusion, abdominal tenderness, peritoneal irritation, and systemic toxicity. The Clostridium difficile assay was negative on two occasions. Features compatible with pseudomembranous colitis were seen at sigmoidoscopy, and the diagnosis was confirmed by biopsies.

Rectal colonization with vancomycin-resistant enterococci among high-risk patients in an Israeli hospital

The prevalence of rectal carriage of vancomycin-resistant enterococci (VRE) in two high-risk populations--61 patients admitted to ICU and 92 patients on renal dialysis--was studied longitudinally over a period of six months in a 650-bed general hospital. ICU patients were swabbed weekly and dialysis patients monthly. Enterococcal isolates were fully identified using the ATB identification system, and MICs were determined according to the NCCLS recommendations. Enterococci were isolated in 52 (83.6%) ICU patients and 86 (93.4%) dialysis patients. VRE were recovered at least once in 14 (27%) ICU patients and four (4.8%) dialysis patients. All VRE isolates (MIC of vancomycin > or = 256 micrograms/mL) were resistant to teicoplanin (MIC > or = 32 micrograms/mL; vanA phenotype), 87.5% were ampicillin-resistant, and 92% showed high-level resistance to gentamicin; 88% were E. faecium. The main risk factors for acquisition of VRE included duration of hospitalization in the six months preceding entry into the study and during the survey (P = 0.009 and 0.007 respectively, for ICU patients), and duration of antibiotic administration (P = 0.005, for ICU patients). The impact of vancomycin was most prominent (P = 0.005 for receipt and 0.06 for duration of administration, in ICU patients). Six of the 18 VRE carriers developed bacteraemia, six isolates being vancomycin-susceptible and one vancomycin-resistant (one patient had both). In this study, the first in Israel, a low rectal carriage rate occurred in renal dialysis patients and antibiotic use was the most important risk factor for VRE colonization.

Use of adsorptive mechanisms in continuous renal replacement therapies in the critically ill

The pathophysiology of sepsis is becoming a more complicated scenario. In sepsis, endotoxin or other gram-positive derived products induce a complex and dynamic cellular response giving rise to several mediators known to be relevant in the pathogenesis of septic shock, such as specific mediators. substances responsible for up- or down-regulation of cytokine receptors and cytokine antagonists, inactivators of nuclear factor-kappaB or signal transduction pathways, and precursor molecules. In this article, we delve into some new concepts stemming from the use of sorbents in continuous plasma filtration. The rationale is based on the assumption that the nonspecific removal of several mediators of the inflammatory cascade and cytokine network may improve outcome in a rabbit model of septic shock and hemodynamics in a pilot clinical study. The importance of looking for innovative treatments specifically targeted for the special needs of the critically ill patients rather than using concepts and technology applied to the treatment of chronic renal failure is underlined.

Value of radiation therapy in the management of chemoresistant intermediate grade non-Hodgkin's lymphoma

The purpose of this study was to evaluate the probability and extent of response to radiation therapy in patients with chemotherapy-resistant intermediate grade non-Hodgkin's lymphoma. Thirty-five patients with chemotherapy-resistant non-Hodgkin's lymphoma received local radiation therapy after initial treatment with at least six cycles of systemic chemotherapy. There were 17 men and 18 women in our study. Ages ranged from 15 to 68 years, median age was 42 years. Chemotherapy resistance was defined as relapse after initial chemotherapy (11 patients) or failure to achieve complete remission (partial response in 18 patients, stable disease in 1 patient, and disease progression in 5 patients). Radiation doses were between 1,980-5,040 cGy (median dose of 3,200 cGy). Treatment outcome was evaluated with respect to any subsequent relapse either within or outside the irradiated region. The 2-year actuarial survival was 65%. The cumulative incidence of isolated local failure and any local failure at 2 years were 33% and 54%, respectively. Tumors that responded to initial chemotherapy had a better local control probability than tumors that did not respond. The 2-year actuarial local failure rates for these two groups were 51% and 83%, respectively (P = 0.01). There was a trend for improved local control with radiation doses > or = 3,960 cGy, suggesting the presence of a dose-control relationship. The rate of disease progression within an irradiated region in patients with intermediate grade non-Hodgkin's lymphoma that relapsed after or failed to respond completely to full course chemotherapy was substantially higher than the historical in-field failure rates when radiation therapy was used as the sole modality of treatment. Prior response to initial chemotherapy was a predicting factor for local control following radiation therapy.

Maternal infectious morbidity following multiple courses of betamethasone

OBJECTIVE

the beneficial effects of antepartum corticosteroids on the reduction of morbidity and mortality in the premature neonate have been amply demonstrated. The NIH consensus statement has, therefore, endorsed their use in women at risk from pre-term delivery between 24 and 34 weeks gestation. Patients at persistent risk of pre-term delivery nay receive multiple weekly courses. However, increased susceptibility to infection is a well-recognized complication of prolonged high-dose steroid therapy. We examined infectious morbidity among women exposed to three or more courses of betamethasone. METHODS AND OUTCOMES MEASURES: thirty-seven patients at risk of pre-term delivery who received three or more courses of betamethasone (median = 6: range 3-10) and 74 normal controls, matched for maternal age, route of delivery, and year of delivery were included in the study. Data on medical care provided to study and control patients between 24 weeks gestation and 6 weeks postpartum were retrieved from centralized medical records. Incidences and types of infections were compared by Chi-square and Fisher's exact test, as appropriate. Only infections diagnosed at least 1 week after betamethasone therapy was initiated were included. Patients with pre-existing conditions predisposing to infectious morbidity were excluded.

RESULTS

twenty-four of 37 patients (64.8%) exposed to betamethasone vs. 13 of 74 (17.5%) controls developed infectious diseases (P < 0.001). Symptomatic lower urinary tract infections occurred in 13 of 37 (35.1%) and two of 74 (2.7%) in the study and control groups, respectively (P < 0.001). Serious bacterial infections were found in nine of 37 (24.3%) vs. none of 74 (0%) patients, respectively (P < 0.001). These included sepsis (n=2), pneumonia (n=4), pyelonephritis (n=2), and cholangitis (n=1). Eight of nine serious infections occurred in patients exposed to five or more weekly courses of betamethasone. Postpartum endometritis related to Caesarean delivery was found in five of 37 patients (13.5%) vs. seven of 74 (9.4%), respectively (P=NS).

CONCLUSIONS

Three or more courses of antepartum betamethasone in women at risk of pre-term delivery are associated with substantial infectious maternal morbidity. The excess morbidity consisted mainly of bacterial infections, some of which were associated with systemic and potentially life-threatening infections.

Results from ethical international surveys on the management of the continuous renal replacement therapy

OBJECTIVE

To examine the ethical approach of clinicians to the continuous renal replacement therapy (CRRT).

DESIGN

Review of international surveys.

RESULTS

Many surveys have been carried out in order to evaluate the clinical approach and management of the continuous renal replacement therapy (CRRT). Nothing has been proposed in order to evaluate it from a bioethical point of view, even if many surveys dealt with the problem of the ethically correct administration of vital supports. These data demonstrate that an ethically correct approach to the management of life-saving support can be sometimes difficult. Results of a recent study on the ethical approach of intensivists and nephrologists to CRRT will be shown and discussed.

CONCLUSIONS

Several ethical questions in the management of CRRT and other vital support are still unsolved. Practical and psychological aspects of the curing process are sometimes stronger than bioethical principles.

Present and future options in continuous renal replacement therapies of sepsis and MOF

Conventional continuous extracorporeal treatments such as hemofiltration and hemodiafiltration have not achieved significant reduction in cytokine plasma levels, in spite of their increasing popularity mainly related to the unnecessary fluid restriction thereby rendering adequate caloric intake possible (Actualités Nephrologiques, 1994). This is mainly due to reduced filtration, to saturability of the adsorption-related phenomena and to the absence of a convective mass transfer. New approaches have been more recently introduced. The concept of blood purification has been applied in some new innovative techniques that use non-selective or selective sorbents. We will focus on the criteria used by others and us to assess the efficiency in vitro and in animal models of sepsis of more recently introduced non-selective and selective devices. Among the innovative techniques, modalities aimed at the plasma treatment will receive emphasis. These modalities that are based on plasma filtration with the use of different sorbents. The preliminary results obtained from ongoing clinical trials will be presented. We will also expand on the technical, biological and clinical aspects that should be addressed in order to establish a new modality as innovative in the treatment of sepsis.

Concentration and bactericidal activity of fusidic acid and cloxacillin in serum and synovial fluid

Fusidic acid and cloxacillin were studied in patients who underwent joint aspiration for noninfectious disorders. Nine patients were given oral 500 mg fusidic acid tid for 72 h, the last dose being given 4, 8 or 12 h before the joint aspiration. Cloxacillin was administered in a single 2 g iv dose to 9 patients, 0.5, 4 or 8 h before the aspiration. Bactericidal activity was determined against five isolates each of methicillin-susceptible and methicillin-resistant Staphylococcus aureus. Satisfactory activity (> or = 1:3) was detected in the serum in patients who received fusidic acid, while in the synovial fluids titres reflected borderline effectiveness (c. 1:2). Despite drug concentrations and excellent MICs, fusidic acid demonstrated markedly lower inhibitory and bactericidal activity against S. aureus than did cloxacillin.

Expression of membrane-associated macrophage colony-stimulating factor (M-CSF) in Hodgkin's disease and other hematologic malignancies

We have identified a membrane-bound form of M-CSF (m-M-CSF) from an established human leukemic J6-1 cell line. To further understand its biological significance, we studied the expression of this membrane-associated growth factor in the lymph nodes of lymphoma patients and bone marrow smears from patients with hematologic diseases by immunohistochemical staining using anti-M-CSF MAb. We detected a high incidence of m-M-CSF expression in 75% (9/12) of the lymph node sections from patients with Hodgkin's Disease (HD). The antigens were detected primarily in large clusters of mononuclear Hodgkin's cells and the extracellular matrix (EM) surrounding them. In one HD patient with abundant multinucleated Reed-Sternberg (R-S) cells, all of them were intensely stained with anti-M-CSF MAb. In non-Hodgkin's lymphomas (NHL), the incidence (17.6 %) of m-M-CSF expression was lower (3/17). Yet, no m-M-CSF antigens were detected in the lymph nodes from six cases of non-hematologic malignancies and other diseases. A high response also was detected in bone marrow smears obtained from patients with hematologic malignancies, which include myeloid leukemias (32.5%), lymphomas with bone marrow metastasis (50%) and myelodysplastic syndromes (MDS) (37.5 %). By comparison, only 6.8 % of bone marrow smears from non-malignant hematologic diseases and 2.7% of lymphoid leukemias showed positive staining with anti-M-CSF MAb. Our results showed that high expression of m-M-CSF antigens is linked to some types of lymphomas, especially HD. and myeloid leukemias, and may play a role in the development of these hematologic malignancies.

Comparison of ex-vivo serum bactericidal activity of cefepime, ceftazidime and cloxacillin against Staphylococcus aureus

Cefepime (1 g), ceftazidime (1 g), and cloxacillin (2 g) were administered intravenously to 10 volunteers each. After infusion of a single dose over 30 min, blood samples were obtained at 0.5, 1, 2, 3, 4, 5, 6, 8, 10, and 12 h (for ceftazidime at 0.5 and 4 h) after dosing. Drug levels were determined by the bioassay method. Serum bactericidal activity against five clinical isolates of cloxacillin-susceptible Staphylococcus aureus were determined by the microdilution method according to the National Committee for Clinical Laboratory Standards guidelines. The mean peak serum level was 76.88 +/- 24.71 mg/L for cefepime, 42.8 +/- 15.98 mL/L for ceftazidime, and 92.81 +/- 24.7 mg/L for cloxacillin. Concentrations of cefepime were detected during the whole testing period (mean trough level, 1.43 +/- 0.9 mg/L at 12 h), whereas concentrations of cloxacillin were measurable up to 5 h after administration (mean trough level, 0.90 +/- 0.97 mg/L). The mean peak reciprocal bactericidal titers were 29.41 for cefepime, 5.6 for ceftazidime, and 377 for cloxacillin. Effective bactericidal titers were detected as long as 5 h for cefepime (approximately 40% of the dosing interval) and 3 h for cloxacillin (at least 50% of the dosing interval). For ceftazidime, serum bactericidal activity was markedly lower compared with that of cefepime. Although cefepime has demonstrated an improved antistaphylococcal bactericidal activity compared with ceftazidime, it was somewhat lower than that of cloxacillin.

[Dissection and cytogenetic localization of the phenotypes of the 5p deletion syndrome]

OBJECTIVE

To classify the phenotypes of the short arm of chromosome 5 (5p) deletion syndrome and to localize their corresponding regions in the human genome.

METHODS

A hundred and six patients, together with most of their parents and sibs, were analysed both cytogenetically and clinically. The dissection of the syndrome and cytogenetic localization of each phenotype was made by relating the clinical data to the breakpoints involved in the deletions.

RESULTS

The 5p deletion syndrome was classified into 8 types based on the combination of the clinical data and high-resolution banding analysis.

CONCLUSIONS

The dissection of the "5p deletion syndrome", a term with refined concept suggested by us, and the cytogenetic localization of each distinct phenotype will provide the clear cut criteria for clinical and cytogenetic diagnosis of the 5p-patients, as well as the candidate regions for positional cloning of the gene(s) repossible for the phenotypes.

Accelerated streptokinase--a new thrombolytic regimen in acute myocardial infarction

Efficiency and safety of an accelerated regimen of streptokinase (1.5 M.U. over 20 min., 109 patients) has been compared with the standard regimen (1.5 M.U. over 60 min, 119 patients) in 218 patients admitted within the first 6 hours after the onset of the symptoms of acute myocardial infarction. Using the noninvasive criteria we found a coronary reperfusion rate of 77.04% in patients belonging to the accelerated regimen group and this value was significantly higher than the one of 57.14% registered in the standard group. No major hemorrhagic events were registered in both groups. Although the hypotension appeared to be more frequent in patients in whom the accelerated regimen was used, however this side effect proved to be transient and well controlled using the rapid infusion of natrium chloride solution. In conclusion, the accelerated regimen of streptokinase is safe and followed by a higher rate of coronary reperfusion as compared to the standard one.

Serum bactericidal activity of newer oral cephalosporins in healthy volunteers

The serum bactericidal activity of three oral cephalosporins was studied in 12 volunteers, after administration of single doses of cefuroxime axetil 250 mg, cefixime 200 mg, cefixime 400 mg and cefetamet pivoxil 500 mg. Serum bactericidal activity against clinical isolates of Streptococcus pyogenes, Streptococcus pneumoniae, Haemophilus influenzae and Klebsiella pneumoniae was measured by a standardized microdilution method. Cefuroxime axetil demonstrated the best bactericidal activity against Gram-positive organisms and cefixime was the most bactericidal against Gram-negative bacteria.

Lectin binding patterns of odontogenic epithelium in the rat during various phases of molar tooth development

Light and electron microscopic investigations of lectin binding patterns in rat tooth germs were undertaken in order to elucidate glycoconjugate localization in cells of the reduced enamel epithelia and their derivatives. It was found that Ulex europaeus agglutinin (UEA-1), peanut agglutinin (PNA), soybean agglutinin (SBA), and wheat germ agglutinin (WGA) exhibited variable reactivity patterns with different epithelia. UEA-1 was reactive with cells of the stratum intermedium and stellate reticulum in the tooth germ but unreactive with ameloblasts, outer enamel epithelial cells, and junctional epithelium at later stages. Reaction patterns of PNA in these cells differed from those of UEA-1. Results indicated that inner and outer cells of the reduced enamel epithelium are heterogeneous with regard to lectin binding patterns.

Successful management of an infected implantable cardioverter defibrillator with oral antibiotics and without removal of the device

Infection of an implantable cardioverter defibrillator developed 2 weeks after implantation, presenting with fever, swelling, redness, and tenderness of the skin above the generator site. A cloxacillin resistant coagulase-negative staphylococcus was repeatedly cultured from the abdominal wall pocket fluid. The infection was successfully treated with a combination of two antibiotics, fusidic acid and rifampin, given orally for 3 months. Although the device was not removed, infection did not recur during a 24-month follow-up.

Comparative periurethral bacteriology of uncircumcised and circumcised males

BACKGROUND

It has been established that lack of circumcision increases the risk of urinary tract infection in infants. During the first six months, the presence of foreskin is associated with a greater quantity and a higher concentration of uropathogens in the periurethral area. Very little is known about this association in older males.

OBJECTIVE

To compare the periurethral bacteriology of uncircumcised healthy males of more than one year of age.

METHODS

The periurethral area of 125 uncircumcised and 46 circumcised healthy males (mean age, 26.5 and 28.3 years, respectively) was swabbed and cultured for facultative and anaerobic bacteria, genital mycoplasmas and Chlamydia trachomatis.

RESULTS

Facultative Gram positive cocci predominated in both groups (62% and 80%, respectively). Pure culture of facultative Gram negative rods was more common in uncircumcised males (17% v 4% in circumcised males, p = 0.01). Streptococci, strict anaerobes and genital mycoplasmas were found almost exclusively in uncircumcised males of more than 15 years of age. No case of C trachomatis was identified.

CONCLUSIONS

The higher prevalence of potential uropathogens in the subpreputial space is in accordance with a previous finding of increased risk of urinary tract infection in uncircumcised young men. Our results also support the role of the prepuce as a reservoir for sexually transmitted organisms.

Serum concentrations and ex vivo inhibitory/bactericidal activity of clindamycin after administration of two oral dosages

Two dosages of clindamycin, 300 and 600 mg, were given orally to 10 patients each. The patients were admitted for minor elective surgery. Their mean age was 39.3 years; mean weight was 67.5 kg. None of them had taken antibiotics for at least 1 month. After administration of a single dose, blood samples were obtained at 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10 and 12 h after dosing. Drug levels were determined by the bioassay method using Micrococcus luteus as test organism. Serum inhibitory and bactericidal activities against five isolates each of Staphylococcus aureus and Streptococcus pyogenes were determined by the microdilution method according to the National Committee for Clinical Laboratory Standards guidelines. The mean peak serum level was 3.4 mg/l for the 300-mg dose and 4.8 mg/l for the 600-mg dose. The mean reciprocal peak inhibitory titers for the 300-/600-mg doses were 13.7/23.8 and 15.2/34.7 against S. aureus and S. pyogenes, respectively. Most serum samples did not show bactericidal activity against S. aureus.

Pyrazinamide-induced granulomatous hepatitis

Noncaseating granulomatous hepatitis may be caused by a variety of drugs, but we have not found, by computer search of the literature, a previous describe of granulomatous hepatitis associated with pyrazinamide. We describe a 52-year-old man with hectic fever, chills, extreme fatigue, liver damage, and hyperuricemia about 4 weeks after commencing pyrazinamide therapy. A liver biopsy specimen showed noncaseating epithelioid granulomas. The patient recovered soon after the interruption of tuberculostatic treatment.

Modified thioglycolate medium: a simple and reliable means for detection of Trichomonas vaginalis

Despite the declining rate of sexually transmitted diseases in developed countries, trichomoniasis is still one of the most common venereal infections. While diagnosis of this condition is commonly based on the microscopic wet-mount method, culture remains the most accurate single procedure for detecting the presence of Trichomonas vaginalis in clinical samples. In the present study, the efficacy of a modified formula of the commonly available thioglycolate medium was compared with that of the standard Diamond's medium for detection of T. vaginalis in samples from 176 women with vaginal symptoms. Thioglycolate medium supplemented with yeast extract, horse serum, and antimicrobial agents was as reliable as Diamond's medium for detection of T. vaginalis in vaginal fluid samples. Modified thioglycolate medium may be used as a readily available, low-cost substitute for the standard medium for culturing T. vaginalis.

Malaria Imported by Travelers: The Israeli Experience

Indigenous malaria has been successfully eradicated in North America, Europe, and a few other previously endemic locations. Extensive antimalarial programs, improvement of health care services, and advances in socioeconomic development have all contributed to one of the most significant achievements in public health of the 20th century.1 Nevertheless, a new malaria transmission pattern is increasingly seen in these areas nowadays. The constantly mounting movement of travelers from developed countries to the tropics and the affluent immigration to the industrialized world from countries where malaria has remained endemic are responsible for the emergence of imported malaria.2 Most physicians who studied medicine in developed countries, although familiar with the classic presentation of the disease, have rarely seen a single case of malaria during training and believe that it is an exotic illness existing elsewhere. It is important therefore to characterize the demographic and clinical features of imported malaria, which is practically the only malaria now seen in the industrialized world, and to make it more familiar to health care providers. This need is further emphasized by the emerging problem of drug-resistant malaria, which may be atypical in patients who had received inappropriate prophylaxis. In Israel malaria is almost exclusively an imported disease. It occurs in Israelis who visit or work in endemic areas and in immigrants, invariably from Ethiopia. The majority of Ethiopian immigrants arrived in two waves in 1985 and 1991 and do not represent an ongoing malaria problem.3 The features of the disease in this population were extensively reported elsewhere.3,4 In the present report we examine the characteristics of malaria imported to Israel by travelers.

Penetration and bactericidal activity of cefixime in synovial fluid

The penetration of oral cefixime into the synovial fluids of 16 patients (mean age, 50.6 years) who underwent joint taps for rheumatic noninfectious disorders was examined. The patients were each given a single dose (400 mg) 2 to 24 h prior to the tap. Cefixime concentrations in serum and joint fluid samples were measured by high-performance liquid chromatography, and the bactericidal activities of these fluids against three isolates each of Haemophilus influenzae and Escherichia coli were examined. The highest concentrations in serum and synovial fluid were achieved 4 h following drug intake, the mean values being 2.8 and 2.03 micrograms/ml, respectively. Effective bactericidal activities (bactericidal titer, > 1:2) against E. coli and H. influenzae were demonstrated in serum and joint fluid up to 10 h following oral intake of cefixime. These results suggest that cefixime penetrates well into joint fluid, achieving levels above the MIC for E. coli lasting as long as 10 h and levels above the MIC for H. influenzae lasting up to 24 h after administration. Good bactericidal activity against susceptible bacterial isolates was observed for at least 10 h after dosing.

Penetration of cefetamet pivoxil and cefuroxime axetil into the maxillary sinus mucosa at steady state

The penetration of cefetamet and cefuroxime into the maxillary sinus mucosa after the administration of cefetamet pivoxil and cefuroxime axetil was investigated in patients undergoing elective surgery of the maxillary sinus. A total of 27 patients, 13 for cefetamet pivoxil and 14 for cefuroxime axetil, ranging from 15 to 70 years of age participated in this study. Each patient received three oral doses of either one tablet of cefetamet pivoxil (500 mg of GLOBOCEF) or two film tablets of cefuroxime axetil (125 and 250 mg of ZINAT) every 12 h. Sinus mucosa tissue samples were removed during surgery at times ranging from 2 to 4.5 h after the last oral administration. Blood samples were collected before drug administration, 2 h after the first and third doses, and concomitantly with tissue sample collection during surgery. All samples were analyzed by high-performance liquid chromatography. The concentrations of cefetamet and cefuroxime in plasma samples measured concomitantly with those in tissue samples ranged between 0.83 and 4.5 micrograms/ml for cefetamet and 0.59 and 3 micrograms/ml for cefuroxime. The mean tissue-to-plasma ratios calculated with reference to total (bound plus unbound) plasma drug concentrations were 0.60 (range, 0.52 to 0.77) for cefetamet (n = 4) and 0.38 (range, 0.28 to 0.44) for cefuroxime (n = 6). Both drugs seem to penetrate freely and easily into the sinus mucosa. The antibacterial activities of cefetamet pivoxil and cefuroxime axetil in cases of sinusitis therefore depend mainly on their achieved active plasma drug concentrations and their intrinsic activities in inhibiting the causative organism(s).

Schistosomiasis Acquired in Lake Malawi

Background: Schistosomiasis is second only to Malaria in its prevalence in the tropics. The mode of transmission of this disease is unknown to many travelers, whereas other travelers consciously choose to ignore recommendations offered by travel clinics. Methods: We present a descriptive analysis of 22 patients who presented with S. haematobium (SH) infection to two travel clinics in Israel during 1993 and 1994. Results: All 22 patients (mean age 24.2 yrs) apparently acquired SH in lake Malawi. The group contained seven couples, which indicates a very high attack rate. Three of the cases were asymptomatic, thereby causing a diagnostic delay of up to 52 weeks. Diagnosis was established in 18 cases by finding eggs in the urine, and in eight cases, by serology. Conclusion: All cases of SH diagnosed at two medical centers in Israel in 1993 and 1994 were acquired in Lake Malawi. A few of the cases were totally asymptomatic, which raises the question of routine screening. Travel clinics should warn travelers to the Lake Malawi region of this specific hazard.

Comparative serum bactericidal activity against Pseudomonas aeruginosa of six antipseudomonal agents

Serum levels and serum bactericidal activities of six antipseudomonal agents were studied comparatively in 60 patients. Single intravenous doses of gentamicin (1.5 mg/kg), piperacillin (4 g), ceftazidime (1 g), imipenem (0.5 g), aztreonam (1 g), and ciprofloxacin (200 mg) were given over 30 min to 10 patients each, and serum samples were obtained 30 min, 1, 2, 3, 4, 6, 8 and 12 h after beginning the infusion. Serum bactericidal activity was determined by the broth microdilution method against 10 recent isolates of Pseudomonas aeruginosa. Mean peak serum levels were as follows: gentamicin 10.4 micrograms/ml, piperacillin 227.5 micrograms/ml, ceftazidime 43.5 micrograms/ml, imipenem 17.3 micrograms/ml, aztreonam 42.3 micrograms/ml, and ciprofloxacin 3.9 micrograms/ml. All agents demonstrated effective serum bactericidal activity (geometric mean titer > 1:2) at peak serum levels. Ceftazidime was by far the most potent compound with a mean titer of 1:46.5, followed by ciprofloxacin (1:17), imipenem (1:13.7), and aztreonam (1:13.4). Ceftazidime also showed the longest duration of activity with a mean titer of 1:5.1 at 4 h. Based on our results, ceftazidime appeared to be the most potent antipseudomonal agent, while gentamicin and piperacillin were the least effective.

Phase I trial of sequential cyclophosphamide, cyclosporin A, and interferon-alpha in patients with cancer: attempt to induce autologous graft-versus-host reaction to elicit an antitumor response

Previous reports of autologous bone marrow transplant (auto-BMT) have demonstrated that myeloablative therapy followed by cyclosporin A (CsA), with and without interferon (IFN), can generate autoreactive cytotoxic T lymphocytes (auto-CTL) with potential therapeutic benefit. This is the first report of an attempt to generate auto-CTL using CsA and IFN after a non-myeloablative regimen. Cyclophosphamide (CTX) 1,200 mg/m2 i.v. day 1 was followed by CsA and IFN-alpha days 2-28, administered in a sequential three-step Phase I dose-escalation scheme. Patients were evaluated twice weekly for clinical evidence of graft-versus-host (GVH) reaction. Peripheral blood mononuclear cells (PBMCs) were obtained before treatment, at time of clinical GVH reaction, and days 21 and 28, and analyzed for auto-CTL, natural killer (NK) cell, and lymphokine-activated killer (LAK) cell activity. Patients also underwent punch skin biopsy at the time of clinical GVH reaction or day 21 to identify histologic evidence of GVH. Fourteen patients completed therapy and were evaluable for immunologic studies and anti-tumor response. No increase in auto-CTL, NK cell, or LAK cell activity was seen. Clinical or histologic evidence of GVH reaction did not occur. We conclude that this myelosuppressive dose of CTX combined with CsA and IFN is unable to generate clinical or immunologic evidence of an auto-GVH reaction. Further efforts are warranted to evaluate other therapeutic attempts to generate auto-CTL with anti-tumor activity based on preliminary results of clinical benefit in auto-BMT.

Preliminary experience with pulmonary autografts

Between July 1994 and March 1995, seven patients (six male) with a mean age of 27 years (range 18 to 34 years) were selected for aortic valve replacement with a pulmonary autograft (Ross operation). The aortic valve disease was isolated insufficiency in four cases, stenosis in one and mixed lesion in two. Three patients had a bicuspid aortic valve. Previous cardiac surgical procedures had been performed in two cases (coarctation repair and valvuloplasty in one; isolated aortic valvuloplasty in one). Two patients were in NYHA class II and five in class III. In two cases the autograft was inserted as a scalloped subcoronary implant. Four patients had total aortic root replacement with re-implantation of the coronary ostia. The RVOT was reconstructed with a cryopreserved homograft (five pulmonary two aortic). The aortic cross-clamp time was 150 +/- 10 minutes with a total bypass time of 212 +/- 14 minutes. There was neither operative nor late mortality. Postoperative echocardiography revealed trivial autograft insufficiency in one case with a mean transvalvular gradient of 15.8 mmHg. All patients improved symptomatically (100% in NYHA class I). Freedom from reoperation, valve related complications and endocarditis is 100% at a mean follow up of 5.6 months (range 1-9 months). This preliminary experience supports the concept of pulmonary autograft implantation in selected patients.