D-dimer threshold increase with pretest probability unlikely for pulmonary embolism to decrease unnecessary computerized tomographic pulmonary angiography.

BACKGROUND: Increasing the threshold to define a positive D-dimer could reduce unnecessary computed tomographic pulmonary angiography (CTPA) for a suspected pulmonary embolism (PE) but might increase rates of a missed PE and missed pneumonia, the most common non-thromboembolic diagnosis seen on CTPA. OBJECTIVE: Measure the effect of doubling the standard D-dimer threshold for 'PE unlikely' Revised Geneva (RGS) or Wells' scores on the exclusion rate, frequency and size of a missed PE and missed pneumonia. METHODS: Patients evaluated for a suspected PE with 64-channel CTPA were prospectively enrolled from emergency departments (EDs) and inpatient units of four hospitals. Pretest probability data were collected in real time and the D-dimer was measured in a central laboratory. Criterion standard was CPTA interpretation by two independent radiologists combined with clinical outcome at 30 days. RESULTS: Of 678 patients enrolled, 126 (19%) were PE+ and 93 (14%) had pneumonia. Use of either Wells' ≤ 4 or RGS ≤ 6 produced similar results. For example, with RGS ≤ 6 and standard threshold (< 500 ng mL(-1)), D-dimer was negative in 110/678 (16%), and 4/110 were PE+ (posterior probability 3.8%) and 9/110 (8.2%) had pneumonia. With RGS ≤ 6 and a threshold < 1000 ng mL(-1) , D-dimer was negative in 208/678 (31%) and 11/208 (5.3%) were PE+, but 10/11 missed PEs were subsegmental and none had concomitant DVT. Pneumonia was found in 12/208 (5.4%) with RGS ≤ 6 and D-dimer < 1000 ng mL(-1). CONCLUSIONS: Doubling the threshold for a positive D-dimer with a PE unlikely pretest probability could reduce CTPA scanning with a slightly increased risk of missed isolated subsegmental PE, and no increase in rate of missed pneumonia.

Copper and cadmium: responses in Pseudomonas putida KT2440.

AIMS: To compare responses of a soil bacterium to Cu and Cd. METHODS AND RESULTS: In minimal medium, Cd caused a dose-dependent growth stasis of logarithmic phase cells of Pseudomonas putida, strain KT2440, whereas Cu did not compromise growth up to 10 mg l(-1). Proteomics showed changes in accumulation of both membrane and soluble proteins by 6 h of treatment; increased Krebs cycle enzymes were apparent. Transcript analysis showed Cd- and Cu-induced different genes. Cd-induced genes encoding the transcriptional regulator CzrR2; an outer membrane protein associated with lipopolysaccharide stability, H1; two oxidative stress protective proteins and the P-type ATPase, CadA2, associated with Cd(2+) efflux. The genes most responsive to Cu encoded the regulator CopR1 and the outer membrane resistance protein regulated by CopR1, CopB1; a putative porin, PorD and the Cu-binding protein, PacZ or CopZ, and CopA2. CONCLUSIONS: These findings support that a soil pseudomonad restricts internalization of the metals by using different sets of binding proteins and efflux pumps. Activation of mechanisms to protect against oxidative stress also was evident especially with Cd exposure. SIGNIFICANCE AND IMPACT OF THE STUDY: The differential cellular responses to Cd and Cu suggest that risk assessment for Cd and Cu should be different.

Isolation and characterization of polycyclic aromatic hydrocarbon-degrading Mycobacterium isolates from soil.

Bioremediation of soils contaminated with wood preservatives containing polycyclic aromatic hydrocarbons (PAHs) is desired because of their toxic, mutagenic, and carcinogenic properties. Creosote wood preservative-contaminated soils at the Champion International Superfund Site in Libby, Montana currently undergo bioremediation in a prepared-bed land treatment unit (LTU) process. Microbes isolated from these LTU soils rapidly mineralized the (14)C-labeled PAH pyrene in the LTU soil. Gram staining, electron microscopy, and 16S rDNA-sequencing revealed that three of these bacteria, JLS, KMS, and MCS, were Mycobacterium strains. The phylogeny of the 16S rDNA showed that they were distinct from other Mycobacterium isolates with PAH-degrading activities. Catalase and superoxide dismutase (SOD) isozyme profiles confirmed that each isolate was distinct from each other and from the PAH-degrading mycobacterium, Mycobacterium vanbaalenii sp. nov, isolated from a petroleum-contaminated soil. We find that dioxygenase genes nidA and nidB are present in each of the Libby Mycobacterium isolates and are adjacent to each other in the sequence nidB-nidA, an order that is unique to the PAH-degrading mycobacteria.

Both solar UVA and UVB radiation impair conidial culturability and delay germination in the entomopathogenic fungus Metarhizium anisopliae.

The entomopathogenic hyphomycete Metarhizium anisopliae has been used in programs of agricultural pest and disease vector control in several countries. Exposure to simulated solar radiation for a few hours can completely inactivate the conidia of the fungus. In the present study we determined the effect of exposures to full-spectrum sunlight and to solar ultraviolet A radiation at 320-400 nm (UVA) on the conidial culturability and germination of three M. anisopliae strains. The exposures were performed in July and August 2000 in Logan, UT. The strains showed wide variation in tolerance when exposed to full-spectrum sunlight as well as to UVA sunlight. Four-hour exposures to full-spectrum sunlight reduced the relative culturability by approximately 30% for strain ARSEF 324 and by 100% for strains ARSEF 23 and 2575. The relative UV sensitivity of the two more sensitive strains was different under solar UV from that under ultraviolet B radiation at 280-320 nm (UVB) in the laboratory. Four-hour exposures to solar UVA reduced the relative culturability by 10% for strain ARSEF 324, 40% for strain ARSEF 23 and 60% for strain ARSEF 2575. Exposures to both full-spectrum sunlight and UVA sunlight delayed the germination of the surviving conidia of all three strains. These results, in addition to confirming the deleterious effects of UVB, clearly demonstrate the negative effects of UVA sunlight on the survival and germination of M. anisopliae conidia under natural conditions. The negative effects of UVA in sunlight also emphasize that the biological spectral weighting functions for this fungus must not neglect the UVA wavelengths.

Laparoscopic and percutaneous radiofrequency ablation of the kidney: acute and chronic porcine study.

OBJECTIVES: The chronic effects of renal radiofrequency ablation are unknown. Herein, we investigate the anatomic and physiologic sequelae of laparoscopic and percutaneous renal radiofrequency ablation in acute and chronic porcine models. METHODS: Our study comprised two phases-an acute phase and a chronic phase. In the acute phase, bilateral laparoscopic renal radiofrequency ablation was performed in 6 animals (12 renal units), which were euthanized immediately after surgery. In the chronic study, bilateral percutaneous renal radiofrequency ablation was performed in 5 animals (10 renal units). One animal each was euthanized at postoperative day 3, 7, 14, 30, and 90. RESULTS: Ultrasound-monitored laparoscopic (n = 12) and percutaneous (n = 10) radiofrequency ablations of the lower pole of the kidney were technically successful in each instance. No intraoperative complications occurred. In the survival experiments, the radiolesions showed gradual spontaneous resorption and ultimate renal autoamputation, while maintaining pelvocalyceal integrity as confirmed by ex vivo retrograde ureteropyelogram. Serum creatinine and hematocrit remained stable in all survival animals. Postoperative complication occurred in 1 chronic animal with nonobstructive small bowel dilation at autopsy. CONCLUSIONS: Laparoscopic and percutaneous renal radiofrequency ablation are technically feasible. The anatomic and physiologic sequelae of renal radiosurgery are favorable. Improved techniques of real-time monitoring of the evolving renal radiolesion are necessary.

Meeting American Diabetes Association guidelines in endocrinologist practice.

OBJECTIVE: To determine whether American Diabetes Association (ADA) guidelines can be met in the context of routine endocrinology practice. RESEARCH DESIGN AND METHODS: Charts were reviewed for a group of patients who were examined in 1998, followed for > or = 1 year, and had two or more visits during that year. Process measures and metabolic outcomes were studied for patients with type 2 diabetes, and glycemic control was assessed for patients with type 1 diabetes. RESULTS: A total of 121 patients with type 2 diabetes had a mean age of 63 years, a mean BMI of 31 kg/m2, and a mean duration of diabetes of 12 years. Many had comorbidities or complications: 80% had hypertension, 64% had hyperlipidemia, 78% had neuropathy, 22% had retinopathy, and 21% had albuminuria. Management of type 2 diabetic patients was complex: 38% used oral hypoglycemic agents alone (54% of these were using two or more agents), 31% used oral hypoglycemic agents and insulin, and 26% used insulin alone; 42% of patients taking insulin therapy injected insulin three or more times per day. Within 12 months, 74% of patients had dilated eye examinations, 70% had lipid profiles, and 55% had urine albumin screening. Of the patients, 87% had a foot examination at their last visit. Blood pressure levels averaged 133/72 mmHg, cholesterol levels averaged 4.63 mmol/l, triglyceride levels averaged 1.99 mmol/l, HDL cholesterol levels averaged 1.24 mmol/l, and LDL cholesterol levels averaged 2.61 mmol/l. Random blood glucose levels averaged 8.0 mmol/l, and HbAlc levels averaged 6.9 +/- 0.1%. A total of 87% of patients had HbAlc levels < or = 8.0%. A total of 30 patients with type 1 diabetes had mean age of 44 years, a mean BMI of 26 kg/m2, and a mean duration of diabetes of 20 years. All type 1 diabetic patients used insulin and averaged 3.4 injections a day; their average HbAlc level was 7.1 +/- 0.2%, and 80% had HbAlc levels < or = 8.0%. CONCLUSIONS: Although endocrinologists must manage patients with multifaceted problems, complex treatment regimens yield glycemic control levels comparable with the Diabetes Control and Complications Trial and allow ADA guidelines to be met in a routine practice setting.

Transcriptional regulation by iron of genes encoding iron- and manganese-superoxide dismutases from Pseudomonas putida.

Genes from Pseudomonas putida (Pp), sodA, encoding manganese-superoxide dismutase (MnSOD) and, sodB, iron-superoxide dismutase (FeSOD) were cloned by hybridization with digoxigenin (dig)-labeled PCR products generated from Pp genomic DNA. The sodB gene had a 594 bp open reading frame (ORF), corresponding to 198 amino acids (aa), and a transcript of 880 bases. The sodA gene contained a 609 bp ORF encoding 203 aa and was transcribed as part of a polycistronic operon, consisting of orfY-fumC-orfX-sodA. Pp sodA or sodB genes both restored aerobic growth, growth on paraquat, and growth on minimal medium to an Escherichia coli (Ec) mutant deficient in SOD activity. Paraquat treatment did not enhance mRNA transcription of the sod genes or increase SOD activity in Pp. The Pp sodB gene was highly expressed throughout logarithmic-(log) growth phase and stationary-phase cells grown in medium supplemented with FeCl3, but was down-regulated in iron-deficient conditions, such as in stationary-phase or generated by 2,2'-dipyridyl (DP) treatment. This is the first evidence that iron regulates expression of the sodB gene at the transcriptional level. In contrast, iron-deficient conditions, or addition of MnCl2 to the growth medium, induced transcripts (2.4 kb and 1.2 kb) from the sodA operon. Our results reveal an intricate role of iron in the transcriptional regulation of both Pp sodA and sodB genes.

Arthroscopic reconstruction of traumatic anterior instability of the shoulder: the Caspari technique.

In a prospective study, all patients with recurrent traumatic anterior instability of the shoulder were treated by an arthroscopic transglenoid suture reconstruction; 163 consecutive patients were treated during the 3-year period of the study. The average number of dislocations per patient was 11, average age 27 years, and the average preoperative Bankart score 15. All patients underwent reconstruction using the Caspari technique of arthroscopic suture reconstruction. Of the 163 patients, 161 were re-evaluated 36 to 72 months postoperatively. Overall, 147 (91%) of the patients rated as satisfactory and 14 (9%) rated as unsatisfactory. The average postoperative Bankart score for all patients was 89. Twenty of 27 patients (76%) younger than age 18 achieved a satisfactory result. Forty-nine of 54 college-age patients achieved a satisfactory result. In patients older than 22 years, 97.5% (78 of 80) achieved a satisfactory result. In this extensive study, it would appear that the success of this arthroscopic technique is age-related, with younger patients having a less successful result than older patients. Arthroscopic reconstruction with this technique provides results equal to those of the open procedure for patients age 22 years and older and would provide a success rate of 90% in patients age 18 to 22. However, it is effective only 74% of the time in patients younger than 18 and is not indicated for patients in this age range.

Transcriptional repression of the ovine follicle-stimulating hormone-beta gene by 17 beta-estradiol.

Direct transcriptional inhibition of the gene that encodes ovine FSH beta-subunit (oFSH beta) by 17 beta-estradiol (E2) has been previously demonstrated by our laboratory. To determine which cis-acting elements in the 5'-flanking region of this gene may be involved in E2 regulation, DNA constructs containing deletions of the 5'-end of the oFSH beta gene were fused to a luciferase reporter and tested in transient transfection assays. These oFSH beta-luciferase constructs and the human E2 receptor expression vector (HEO) were transfected into primary cultures of ovine pituitary cells and subsequently tested with E2. Expression of the largest oFSH beta-luciferase construct (-4741 to +759 of oFSH beta) was inhibited 50% by 20 nM E2. Repression was dependent upon cotransfection of estrogen receptor (HEO) and was E2 dose dependent, with an apparent ED50 similar to that of the positive control consensus estrogen-responsive element construct, ERETk-LUC (ED50 = 50 pM). Deletion studies indicated that sequences between- 105 and -84 bp are necessary for this repression. In addition, a synthetic nucleotide containing oFSH beta sequences from - 105 to -72 could direct E2-dependent repression of a heterologous thymidine kinase promoter that drives luciferase expression. Additional experiments showed that no tissue-specific elements were required for either basal expression or E2-directed transcriptional repression. Although there are no consensus DNA response elements for the estrogen receptor between -105 and +759 of the oFSH beta gene, cotransfection of a mutant E2 receptor lacking the DNA-binding domain (HE-11) failed to mediate E2-dependent inhibition. Gel retardation studies, using the oligonucleotide-containing oFSH beta sequences from -105 to -72, indicated no evidence of direct binding of the estrogen receptor to DNA from -105 to -72. The studies presented here indicate that transcriptional repression of the oFSH beta gene by E2 may be directed in vivo by 5'-flanking sequences between -105 and -72 of the oFSH beta gene. Furthermore, the data suggest that inhibition is mediated via E2 receptor-protein interactions with basal transcription factors that may bind to the -105/-72 DNA directly.

Neuroanatomy in elbow arthroscopy.

An injury to the median nerve from within the joint during an arthroscopic synovectomy prompted a study of the relationship of the nerves to the capsule and bones of the elbow. Six pairs of cadaveric elbows frozen in 90 degrees of flexion and one pair frozen in extension were sectioned at 5-mm intervals, and the distances from the major nerves to the bones and capsule were recorded. One elbow joint in each pair was filled with saline solution. Saline solution insufflation increased the nerve-to-bone distance with the elbow in flexion. The results were 12 mm for the median nerve and 6 mm for the radial nerve. The capsule-to-nerve distance was affected little by insufflation and was as narrow as 6 mm in three specimens. Extension eliminated the protective effects of insufflation and brought the nerves closer to the bone. These findings confirm (1) the importance of flexion and insufflation in portal placement, (2) that insufflation does not improve the capsule-to-nerve distance, and (3) the potential for "from within-out" injury in synovial procedures.

The gene encoding ovine follicle-stimulating hormone beta: isolation, characterization, and comparison to a related ovine genomic sequence.

Follicle-stimulating hormone (FSH), the primary stimulus for egg and sperm maturation in mammals, is an alpha/beta heterodimer. Each subunit is encoded by a single-copy gene in the human, bovine, and rat genomes. Transcription of both subunits is inhibited by estradiol and progesterone in ovine pituitary cultures. We report the sequence of one ovine FSH-beta gene (-1,527 to +3,664) that is expressed in vivo and the identification of a novel, second ovine FSH-beta-like sequence. Digestion of ovine genomic DNA with Bgl II yielded two fragments of 10 kb and 15 kb that hybridized to a bovine FSH-beta cDNA. The 10-kb fragment contained 6 kb of 5'-flanking region and all but about 200 bp of the 3' terminus of the ovine FSH-beta gene. This FSH-beta gene encodes a protein that differs from the published ovine protein sequence only at the carboxy terminus (Arg-109Glu-110[STOP codon] instead of Glu-109Arg-110[Glx-111]) and at positions 49 (Ala instead of Thr) and 88 (Arg instead of Ser). This gene is organized similarly to the human, bovine, porcine, and rat FSH-beta genes, and its coding sequence is nearly identical (99.5%) to a reported ovine FSH-beta cDNA. Expression of the FSH-beta gene on the 10-kb fragment in vivo was determined by analysis of wether mRNA using the polymerase chain reaction. A 95-bp sequence of the 15-kb fragment was 87% homologous to the corresponding coding region of the 10-kb fragment. This comparison suggested that the 15-kb fragment contains either an FSH-beta-like sequence or a pseudogene. Several potential steroid response elements were found by sequence analysis of the 5'-flanking region of the FSH-beta gene on the 10-kb fragment. A mechanism by which these elements may act is suggested.

IV lignocaine fails to attenuate the cardiovascular response to laryngoscopy and tracheal intubation.

I.v. lignocaine has been used with varying success to attenuate the cardiovascular responses to laryngoscopy and tracheal intubation. We determined the optimal time of administration in 45 ASA I and II Chinese patients premedicated with morphine and hyoscine, and anaesthetized with thiopentone and suxamethonium. Patients were allocated randomly to a control group or three treatment groups to receive lignocaine 1.5 mg kg-1 i.v. 1, 2, or 3 min before laryngoscopy. Analysis of variance for measured and derived cardiovascular variables failed to show any significant difference between any of the groups.

Comparison of enflurane and halothane in hypotensive eye surgery.

Thirty patients undergoing elective eye surgery had anaesthesia induced with sodium thiopentone, suxamethonium and d-tubocurarine chloride. Patients were ventilated with nitrous oxide, oxygen and either halothane or enflurane. The volatile agents were used to decrease the systolic blood pressure to 80 mmHg. The volatile agent concentration in the blood was measured at 30 min intervals. Both agents were effective in producing hypotension, but enflurane was the more potent hypotensive agent in terms of MAC equivalents. There was no significant differences between the agents with respect to speed of recovery.

Ultraviolet light-induced DNA damage in transcribed sequences: no change in repair with age.

We studied the repair of a plasmid vector containing the chloramphenicol acetyltransferase (CAT) gene by treating the plasmid with UV light and then transfecting this plasmid into fibroblasts from human fetal lung (in vitro aging) and into primary cultured fibroblasts from rat lung and skin. This methodology allows us to examine the repair of specific transcribed DNA sequences. There was no age-related change in the repair of UV damage in these cells. Rat embryo fibroblasts at different passages transfected with the plasmid also revealed no significant alteration in UV repair as a function of passage number.

DNA alterations in prostatic adenocarcinoma and benign prostatic hyperplasia: detection by DNA fingerprint analyses.

DNA fingerprinting can be utilized to examine a large number of autosomal loci throughout the human genome. Alterations in banding patterns observed on DNA fingerprint analyses reflect DNA alterations ranging from single base changes to complex chromosomal rearrangements. In this report, we describe the application of this technique to prostatic adenocarcinoma (CAP) and benign prostatic hyperplasia (BPH). The majority of CAP cases (12 of 14) displayed alterations in at least 1 of the approximately 30 resolvable bands obtained by fingerprint analyses when compared with DNA obtained from peripheral white blood cells. Unexpectedly, 5 of the 12 cases of BPH examined revealed at least 1 identifiable band alteration in the prostatic tissue. These findings demonstrate the usefulness of fingerprint analyses in the examination of cancer-associated genetic alterations. They also suggest the presence of observable genetic alterations in BPH.

Outpatient paediatric dental anaesthesia. A comparison of halothane, enflurane and isoflurane.

One hundred and fifty unpremedicated children who presented for dental extractions were anaesthetised with nitrous oxide and halothane, enflurane or isoflurane. Ventricular arrhythmias occurred only in the halothane group (14%). Respiratory problems and desaturation were significantly more common in the isoflurane group. Induction times differed significantly between the groups halothane less than enflurane less than isoflurane, while recovery time and induction to recovery time were significantly shorter in the enflurane group. We suggest that enflurane is the most suitable agent for anaesthetising these patients.

Human gamma-glutamyl transpeptidase cDNA: comparison of hepatoma and kidney mRNA in the human and rat.

gamma-Glutamyl transpeptidase (GGT) is a glutathione-metabolizing enzyme that has been extensively studied in relation to hepatocarcinogenesis. Using a cDNA for rat kidney GGT as a probe, we have isolated a full-length cDNA for human GGT from a hepatoma cell-line library. Nucleotide sequence analysis of the clone revealed a 2326-bp insert that includes a 5'-untranslated region of 487 nucleotides (nt), an open reading frame (ORF) of 1707 nt, and a 3'-untranslated region of 132 nt. The ORF encodes a protein with an amino acid sequence that is highly similar to that of the rat GGT precursor peptide, with an overall identity of 79%. The cDNA clone was used to probe Northern blots of hepatoma and kidney RNA from both human and rat. In both species, the GGT mRNA is longer in hepatoma than in kidney. In addition, the human mRNAs were longer than their counterparts in the rat. None of three human hepatocellular carcinomas examined showed a marked elevation in GGT mRNA levels relative to surrounding liver tissue.

Effect of a high-intensity static magnetic field on sciatic nerve regeneration in the rat.

The effect of a high-intensity static magnetic field on peripheral nerve regeneration is evaluated in rat sciatic nerve. Forty-four rats underwent sciatic nerve repair using polyethylene nerve guides. Postoperatively, the animals were exposed to a 1-tesla magnetic field for 12 hours per day for 4 weeks with appropriate controls. Our results demonstrate that a 1-tesla static magnetic field has no statistically significant effect on nerve regeneration as determined by myelinated axon counts and electrophysiologic studies. Also, the specific orientation of the sciatic nerve with respect to the magnetic field has no influence on axonal growth or nerve conduction. Periods of restraint of 12 hours per day for 4 weeks significantly inhibit weight gain but have no effect on peripheral nerve regeneration.

Silent regurgitation in day case gynaecological patients.

The effect of metoclopramide premedication on the incidence of gastric regurgitation and postoperative nausea and vomiting was studied in 101 women during gynaecological procedures performed under mask anaesthesia. All patients were premedicated orally with carmine red and temazepam. A treatment group of 48 women also received oral metoclopramide. Anaesthesia was standardised in both groups. None of the women regurgitated gastric contents. Pharyngeal pH was measured in the last 68 patients and found to be greater than 5 in all instances. Postoperative nausea and vomiting were significantly less frequent in the treatment group.