Inducible and constitutive expression of resistance to glycopeptides and vancomycin dependence in glycopeptide-resistant Enterococcus avium.

A clinical isolate of Enterococcus avium, Ea1, which exhibited inducible, low-level resistance to vancomycin and teicoplanin, and two mutants selected from this strain, Ea3 and Ea31, were studied. Ea3 was vancomycin dependent and derived from Ea1, while Ea31 was not vancomycin dependent, was constitutively resistant, and was derived from Ea3. Hybridization studies revealed that vanA was present in Ea1 and suggested that it was located on a high-molecular-weight plasmid. In the absence of induction, Ea1 synthesized only the natural UDP-MurNAc-pentapeptide precursor, and after induction it synthesized an additional precursor identified as UDP-MurNAc-tetrapeptide-D-lactate. The latter was the only precursor found in Ea3 and Ea31, even after precursor accumulation. From these results, we infer that (i) the low level of resistance to glycopeptides in strain Ea1 may be in part due to the residual synthesis of the normal precursor and (ii) the vancomycin dependence of mutant Ea3 could be due to the fact that this strain does not produce any peptidoglycan precursor in the absence of induction.     

Conversion of choledochojejunostomy stents to jejunal feeding tubes for postoperative enteral alimentation

The problem of protein calorie malnutrition following major gastrointestinal surgery can be treated with central venous or enteric alimentation, with the latter being preferred. The authors describe a simple technique for the conversion of biliary stents placed after pancreaticoduodenal surgery into jejunal feeding tubes when the stenting function is no longer needed. Three illustrative cases are presented. In each case, the procedure took less than 30 min and had no associated morbidity. This technique allows early conversion from central venous to enteric alimentation without the need to create a second surgical enterostomy.     

Preliminary characterization of the procoagulant material in human ascites

Disseminated intravascular coagulation invariably accompanies placement of peritoneovenous (LeVeen) shunts, which suggests that ascitic fluid contains procoagulant material capable of activating blood coagulation. In this study, we identified thrombogenic activity in human ascites and the hemostatic pathway by which it acts. Peritoneal fluid was removed percutaneously from patients with ascites due to various causes. Four fractions were prepared by centrifugation: cells, a low-speed, cell-free fluid, a high-speed supernatant, and the precipitate from the high-speed centrifugation. Cellular fractions from all ascitic fluids shortened a one-stage clotting time of normal pooled plasma by 68% in comparison with saline solution and endotoxin controls. Similarly, the cell-free fluids also shortened the clotting time of normal pooled plasma by 41%. The cellular and cell-free fractions shortened the clotting time of factor VIII-deficient plasma but failed to demonstrate procoagulant activity in factor VII-deficient plasma. These fractions had no effect on platelet aggregation or the platelet release reaction. The high-speed precipitate was dissociated by ethylenediaminetetra-acetate (EDTA) into fluid phase and precipitate, both of which demonstrated procoagulant activity. Furthermore, high-speed precipitate contained protein, phospholipid, and sterol in proportions similar to those of plasma membranes and contained membrane-bound vesicles as identified by means of electron microscopy. This material could be rendered inactive by heating to 100 degrees C for 2 minutes or by incubation with phospholipase C for 15 minutes. Finally, the ability of the high-speed precipitate to shorten the clotting time was prevented by preincubation with a monoclonal antibody, which is known to inhibit the procoagulant activity of human tissue factor. We suggest that several entities contribute to the procoagulant properties of human ascites, with procoagulant material deriving at least in part from peritoneal cells. The sedimentable procoagulant factor appears to be associated with cellular membranes or membrane fragments and is thromboplastin-like in its chemical composition, immunoreactivity, and substrate specificity.     

Virulence alterations of Tacaribe virus infection in adult mice: Lethal model for encephalitis

Summary Selection of populations of Tacaribe virus strain 11573 lethal for mice was carried out by serial intracerebral passage of the virus in adult mice. Viral populations have been characterized by determination of virulence for suckling, weanling, and adult mice, and by histopathologic changes observed in brains of adult mice after intracerebral inoculation. Some of the virus preparations produced 80 to 90 per cent mortality after two or three intracerebral passages in adult mice and maintained this virulence for 1 to 3 passages, after which the virulence rapidly declined with subsequent passages. Clinical signs of infection in adult mice were manifested by a rough hair-coat, ventriflexed posture, diminished activity, increased excitability, flaccid hind-limb extension with progressive paralysis and death. Histologic examination revealed meningoencephalitis.With 2 FiguresIn conducting the research described in this report, the investigators adhered to the Guide for the Care and Use of Laboratory Animals, as promulgated by the Committee on the Revision of the Guide for Laboratory Animal Facilities and Care of the Institute of Laboratory Animal Resources, National Research Council. The facilities are fully accredited by the American Association for Accreditation of Laboratory Animal Care.The views of the authors do not purport to reflect the positions of the Department of the Army or the Department of Defense.     

Angiography in poor-risk patients with massive nonvariceal upper gastrointestinal bleeding

The purpose of this retrospective study was to determine the diagnostic and therapeutic usefulness of gut angiography in patients with massive upper gastrointestinal bleeding from a nonvariceal source. All patients (n = 64) in this category who underwent a gut angiogram between 1980 and 1986 were studied. Pre-angiogram endoscopy was attempted in all patients and was nondiagnostic in 14 (22%). Contrast extravasation at angiography was seen in 25 of 64 patients (39%), and in over half of these patients endoscopy was nondiagnostic (n = 11) or wrong (n = 3). Attempts to control bleeding in this group by selective arterial embolization (n = 14) or intra-arterial vasopressin (n = 11) successfully averted operation in 13 of 25 patients (52%) and was associated with a 50% reduction in mortality (83% versus 38%). Selective embolization of vessels thought to be bleeding on clinical grounds without evidence of contrast extravasation (i.e., "blind" embolization) was not helpful in controlling hemorrhage. Urgent gut angiography in patients with massive upper gastrointestinal bleeding of arteriocapillary source is a useful diagnostic and therapeutic maneuver and warrants continued application in this group of poor-risk patients.     

Cancer incidence among first generation Scottish, Irish, West Indian and South Asian migrants living in England and Wales

Objectives. To examine the incidence of cancers among persons born in Scotland, Northern Ireland, the Irish Republic, Caribbean Commonwealth and Indian subcontinent and living in England and Wales. Methods. Longitudinal Study of 1% of population of England and Wales followed from 1971 to 1989. Standardised incidence ratios (SIRs) were derived for commonly occurring cancers and all cancers using the age-sex-specific rates for all females and all males in the Longitudinal Study. Results. The incidence of all malignant neoplasms among West Indians (females SIR = 67, male SIR = 70) and Indians (female SIR = 32, male SIR = 52) was low. Among South Asians, this pattern was consistent for Hindus, Sikhs and Moslems. Scottish females showed raised incidence of lung cancer (SIR = 149) and those from the Irish Republic of oral cavity and pharynx (SIR = 321), oesophageal (SIR = 219) and liver (SIR = 373) cancers. Among Northern Irish females, incidence of lung cancer (SIR = 193) was raised. West Indian and South Asian females showed low incidence of breast cancer (SIR = 55 and 45, respectively). High incidence of laryngeal (SIR = 229) and renal (SIR = 203) cancers was observed for Scottish males and of oral cancer (SIR = 259) for males from the Irish Republic. At ages 15-64, raised incidence of prostate cancer (SIR = 129) and of leukaemia (SIR = 252) was also observed for men from the Irish Republic. Northern Irish males showed raised incidence of stomach cancer (SIR = 200). Conclusion. This study describes patterns of cancer incidence among migrant groups, most of which reflect environmental influences. This has challenging implications for sensitive targeting of primary interventions. It is important not to be complacent about lower risks of main cancers among West Indians and South Asians. In all Longitudinal Study members, breast cancer was the most common malignancy among females and lung cancer among males. This was also true for all migrant groups with the exception of Northern Irish women for whom lung cancer was the most common.     

A phase I trial of the dual farnesyltransferase and geranylgeranyltransferase inhibitor L-778,123 and radiotherapy for locally advanced pancreatic cancer.

PURPOSE: Preclinical and clinical studies have demonstrated that inhibition of prenylation can radiosensitize cell lines with activation of Ras and produce clinical response in patients with cancer. The aim of this study was to determine the maximally tolerated dose of the dual farnesyltransferase and geranylgeranyltransferase I inhibitor L-778,123 in combination with radiotherapy for patients with locally advanced pancreatic cancer. EXPERIMENTAL DESIGN: L-778,123 was given by continuous intravenous infusion with concomitant radiotherapy to 59.4 Gy in standard fractions. Two L-778,123 dose levels were tested: 280 mg/m2/day over weeks 1, 2, 4, and 5 for dose level 1; and 560 mg/m2/day over weeks 1, 2, 4, 5, and 7 for dose level 2. RESULTS: There were no dose-limiting toxicities observed in the eight patients treated on dose level 1. Two of the four patients on dose level 2 experienced dose-limiting toxicities consisting of grade 3 diarrhea in one case and grade 3 gastrointestinal hemorrhage associated with grade 3 thrombocytopenia and neutropenia in the other case. Other common toxicities were mild neutropenia, dehydration, hyperglycemia, and nausea/vomiting. One patient on dose level 1 showed a partial response of 6 months in duration. Both reversible inhibition of HDJ2 farnesylation and radiosensitization of a study patient-derived cell line were demonstrated in the presence of L-778,123. K-RAS mutations were found in three of the four patients evaluated. CONCLUSIONS: The combination of L-778,123 and radiotherapy at dose level 1 showed acceptable toxicity in patients with locally advanced pancreatic cancer. Radiosensitization of a patient-derived pancreatic cancer cell line was observed.     

Formation and antitumor activity of PNU-159682, a major metabolite of nemorubicin in human liver microsomes.

PURPOSE: Nemorubicin (3'-deamino-3'-[2'(S)-methoxy-4'-morpholinyl]doxorubicin; MMDX) is an investigational drug currently in phase II/III clinical testing in hepatocellular carcinoma. A bioactivation product of MMDX, 3'-deamino-3',4'-anhydro-[2'(S)-methoxy-3'(R)-oxy-4'-morpholinyl]doxorubicin (PNU-159682), has been recently identified in an incubate of the drug with NADPH-supplemented rat liver microsomes. The aims of this study were to obtain information about MMDX biotransformation to PNU-159682 in humans, and to explore the antitumor activity of PNU-159682. EXPERIMENTAL DESIGN: Human liver microsomes (HLM) and microsomes from genetically engineered cell lines expressing individual human cytochrome P450s (CYP) were used to study MMDX biotransformation. We also examined the cytotoxicity and antitumor activity of PNU-159682 using a panel of in vitro-cultured human tumor cell lines and tumor-bearing mice, respectively. RESULTS: HLMs converted MMDX to a major metabolite, whose retention time in liquid chromatography and ion fragmentation in tandem mass spectrometry were identical to those of synthetic PNU-159682. In a bank of HLMs from 10 donors, rates of PNU-159682 formation correlated significantly with three distinct CYP3A-mediated activities. Troleandomycin and ketoconazole, both inhibitors of CYP3A, markedly reduced PNU-159682 formation by HLMs; the reaction was also concentration-dependently inhibited by a monoclonal antibody to CYP3A4/5. Of the 10 cDNA-expressed CYPs examined, only CYP3A4 formed PNU-159682. In addition, PNU-159682 was remarkably more cytotoxic than MMDX and doxorubicin in vitro, and was effective in the two in vivo tumor models tested, i.e., disseminated murine L1210 leukemia and MX-1 human mammary carcinoma xenografts. CONCLUSIONS: CYP3A4, the major CYP in human liver, converts MMDX to a more cytotoxic metabolite, PNU-159682, which retains antitumor activity in vivo.     

Incidence of complications of thyroid surgery

BACKGROUND: Thyroid surgery presents a low incidence of complications. Death is certainly a rare, or even exceptional event. Hypoparathyroidism, above all if definitive, is the main complication of total thyroidectomy with percentages that very between 0 and 10% in the literature (average 2%). METHODS: The incidence of recurrent lesions varies between an improbable 0% to 8%, whereas lesions to the superior laryngeal nerve are relatively frequent, but often undervalued. Dysphagia, although always transient, presents a high risk of pneumonia ab ingestis and severe dehydration. Hemorrhage has an incidence of 0.1-3.8% and infection is reported in approximately 1% of cases. The permanent and recurrence nature of thyroid pathology in literature is between 5 and 11%, resulting from inadequate or sometimes useless surgery. Hypothyroidism is the logical consequence of total thyroidectomy. In the light of these data we have re-examined 300 operations involving thyroid pathology performed by the same team using the same method over the past 4 years (82% females, 18% males). 33% of the cases presented benign euthyroid nodular pathology, 27% hyperfunctioning benign nodular pathology, 2.6% Flajani-Basedow-Graves disease, 9% were adenomas, 7% were differentiated carcinomas, 2% anaplastic carcinomas and 0.7% medullary carcinomas. 99 extracapsular total loboisthmectomies, 135 total extracapsular thyroidectomies and 66 subtotal thyroidectomies were performed. RESULTS: The following complications were observed: 31/300 symptomatic hypocalcemias of which 25 were transient and 6 (2%) were definitive but easily controlled with treatment; 9 recurrent monoplegias out of 501 isolated recurrent forms of which 4 (0.8%) was permanent; 5/300 (1.7%) postoperative dysphagias associated with recurrent monoplegia in 4 cases. Damage to the external branch of the superior laryngeal nerve was suspected in 11/300 cases (3.7%). Postoperative hemorrhage occurred with an incidence of 1.3%, whereas the incidence of wound infection and serous collection was 1.7%. Moreover, persistent hyperthyroidism after subtotal bilateral thyroidectomy was observed secondary to toxic plurinodular struma. A case of paralysis of the right ulnar nerve, when the arm was adducted, was observed on the operating table, but regressed after about 4 months. Mortality was zero. CONCLUSIONS: Thyroid surgery is still hampered by a relatively low percentage of complications, which are probably still the result of various technical limitations, and it appears difficult to reduce these, let alone eliminate them completely.     

Area of residence and alcohol‐related mortality risk: a five‐year follow‐up study

Aims To examine differences in alcohol‐related mortality risk between areas, while adjusting for the characteristics of the individuals living within these areas. Design A 5‐year longitudinal study of individual and area characteristics of those dying and not dying from alcohol‐related deaths. Setting The Northern Ireland Mortality study. Participants A total of 720 627 people aged 25–74, enumerated in the Northern Ireland 2001 Census, not living in communal establishments. Measurements Five hundred and seventy‐eight alcohol‐related deaths. Findings There was an increased risk of alcohol‐related mortality among disadvantaged individuals, and divorced, widowed and separated males. The risk of an alcohol‐related death was significantly higher in deprived areas for both males [hazard ratio (HR) 3.70; 95% confidence interval (CI) 2.65, 5.18] and females (HR 2.67 (95% CI 1.72, 4.15); however, once adjustment was made for the characteristics of the individuals living within areas, the excess risk for more deprived areas disappeared. Both males and females in rural areas had a reduced risk of an alcohol‐related death compared to their counterparts in urban areas; these differences remained after adjustment for the composition of the people within these areas. Conclusions Alcohol‐related mortality is higher in more deprived, compared to more affluent areas; however, this appears to be due to characteristics of individuals within deprived areas, rather than to some independent effect of area deprivation per se. Risk of alcohol‐related mortality is lower in rural than urban areas, but the cause is unknown.