Classification systems for supraglottic laryngeal carcinoma.
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Biomedical subjects
Publications and source records attributed to J Freeman.
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Discussion of acceleration protection measures should be based on analysis of relevant accident data, including determination of high risk aircraft, G profiles, and pilot descriptions. There were 18 accidents (14 fatalities) attributed to G-induced loss of consciousness (G-LOC) in the United States Air Force (USAF) from 1982 through 1990. All 18 accidents occurred during single crewmember sorties, for an average rate of 2.1 per million single-seat flying hours (pmfh). The average G-LOC accident rate for 1982-4 was 4.0 pmfh, decreasing significantly to 1.3 pmfh for 1985-90. This decrease is associated with the USAF initiation of an anti-G-LOC training program. We reviewed accident records for G-LOC cofactor data and compared them to normal data for USAF pilots for age, height, weight, systolic and diastolic blood pressures, heart rate, total flying time, and aircraft-specific flying hours. Only for systolic blood pressure (higher) and aircraft-specific flying hours (shorter) were the mishap pilots significantly different from other USAF pilots. We found no evidence to support weight training vs. aerobic training, missed meals, or heat in causing G-LOC accidents. Thus the mishap pilots appeared to be a representative cross section of USAF pilots with respect to personal variables. More significant factors appeared to be G duration, G magnitude, use of G trousers, and experience in assigned aircraft.
Molecular modelling and energy minimisation calculations that incorporate solvent effects have been used to investigate the complexation of delta and lambda-[Ru(1,10-phenanthroline]2+ to DNA. The most stable binding geometry for both enantiomers is one in which a phenanthroline chelate is positioned in the major groove. The chelate is partially inserted between neighbouring base pairs, but is not intercalated. For delta, though not for lambda, a geometry with two chelates in the major groove is only slightly less favourable. Minor groove binding is shown to be no more favourable than external electrostatic binding. The optimised geometries of the DNA/[Ru(1,10-phenanthroline]2+ complexes enable published linear dichroism spectra to be used to determine the percentage of each enantiomer in the two most favourable major groove sites. For delta 57 +/- 15% and for lambda 82 +/- 7% of bound molecules are in the partially inserted site.
Fifteen cases of oromandibular reconstruction using a radial osteocutaneous flap were compared with 16 in which the mandible was replaced with a reconstruction plate and a forearm flap was used for intraoral lining. All cases involved oral cancer; most had been irradiated. Nine survived in each group. Complications included one infected nonunion in addition to two bone exposures in the bone group, compared with three cases of plate exposure and two bone exposures in the plate group. Functional results were similar in both, but osteointegrated implants were possible only in the patients receiving bone. Cosmesis seemed somewhat better in the plate group. Donor-site problems were common but minor, and long-term forearm function was slightly reduced in both groups. Although the sample sizes were small, the reconstruction plate together with a radial forearm flap appeared to provide effective reconstruction following composite resection. However, we would not recommend this for the younger patient or in benign disease.
Thirty two patients with refractory or recurrent acute leukemia or blast crisis of chronic myelocytic leukemia were treated with 1-beta-D-arabinofuranosylcytosine (Ara-C), 100 mg/m2 [group I (n = 15)] or 200 mg/m2 [group II (n = 18)], and tetrahydrouridine (THU) 350 mg/m2, given concurrently as a 3 h continuous intravenous infusion at 12 h interval for eight doses. Two of 13 (15.3%) evaluable patients in group I achieved a complete response, both of whom had acute myelocytic leukemia. In group II, seven of 14 evaluable patients (50%) obtained objective responses--six with complete responses (42.8%) and one with partial response (7%). Myelosuppression was seen in all patients with a median duration of 32.5 days (group I) and 36.3 days (group II), respectively. Non-hematologic toxicity consisted of nausea, vomiting, diarrhea, conjunctivitis, skin rash, hepatocellular toxicity, hemorrhage, and renal toxicity. Pharmacokinetic studies revealed, for group I, mean peak plasma Ara-C levels at 3 h (Cp3h) of 1254 ng/ml, area under the curve (AUC) 4651 ng x h/ml, total body clearance (TBC) 32.65 l/h/m2, renal clearance (RC) 7.04 l/h/m2 with a mean of 12.36% of the injected amount of Ara-C excreted unchanged in urine over the first 24 h. The corresponding mean values for group II are Cp3h 3305 ng/ml, AUC 15080 ng x h/ml, TBC 20.48 l/h/m2, RC 7.02 l/h/m2 and 26.23%. Ara-C 200 mg/m2 combined with THU gave serum Ara-C levels and response rates comparable to those achieved with high dose Ara-C (HiDAC) (greater than or equal to 1 g/m2). Central nervous system toxicity associated with HiDAC was not seen. Pharmacokinetics for uracil arabinoside (Ara-U) in patients treated with Ara-C 200 mg/m2 plus THU, were comparable to values seen with Ara-C for Cp3h, AUC and 24 h urine, amounting to 3160 ng/ml, 21717 ng x h/ml and 23.62% whereas TBC was significantly lower (p less than 0.001) for Ara-U than for Ara-C (3.02 versus 20.48 l/h/m2).
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BACKGROUND AND METHODS: Coagulase-negative staphylococci are now the chief cause of bacteremia in neonatal intensive care units. To investigate potential risk factors for this nosocomial infection, we conducted a case--control study among 882 infants treated in two neonatal intensive care units during 1982. RESULTS: The 38 case patients and 76 controls were similar with respect to 27 indicators of the severity of the underlying illness. In addition, of the 20 potential risk factors for bacteremia that we investigated, only 2 met conventional criteria for causality. Infants with coagulase-negative staphylococcal bacteremia were 5.8 times as likely as controls (95 percent confidence interval, 4.1 to 8.3) to have received intravenous lipid emulsion before the onset of bacteremia. Because the use of lipids was common, 56.6 percent of all of the cases of nosocomial bacteremia could be attributed to lipid administration. Infants with bacteremia were also 3.5 times as likely as controls (95 percent confidence interval, 1.4 to 8.3) to have had a percutaneously inserted central venous catheter (attributable risk, 14.9 percent). The induction time for bacteremia after lipid administration, usually through peripheral catheters, was often less than one day. In contrast, the average induction period for nosocomial bacteremia associated with the use of central catheters, which were rarely used for lipid administration, was at least 5.5 days. Similar analyses of data on an additional 31 neonates treated in 1988 confirmed the strong and apparently independent association of coagulase-negative staphylococcal bacteremia with the intravenous administration of lipids (adjusted odds ratio, 5.3; 95 percent confidence interval, 3.5 to 6.7). CONCLUSIONS: The risk of coagulase-negative staphylococcal bacteremia in infants in neonatal intensive care units can be attributed primarily to the intravenous administration of lipid emulsions. Since lipids are critical for the nutritional support of premature infants, further studies are needed to examine the pathogenesis and prevention of lipid-associated bacteremia.
Coagulase-negative staphylococci were the leading cause of nosocomial bacteremia in the neonatal intensive care units of the Brigham and Women's Hospital and Children's Hospital, Boston, Mass, in 1982. To determine the consequences of these nosocomial bacteremias, a cohort study was conducted in which two comparison subjects were matched with each of 38 bacteremic infants by hospital, birth weight within 100 g, and nearest date of discharge. To adjust for duration of stay in the hospital, it was also required that both comparison subjects have survived and remained in the hospital for as long as the time until bacteremia occurred in the bacteremic infant. The average day of onset of bacteremia was the 20th hospital day. Despite having similar birth weights and comparable severity of underlying illness, bacteremic infants remained in the hospital for an average of 19.8 days longer than the nonbacteremic comparison subjects (77.3 vs 57.5 days). The bacteremic patients received antibiotics for an average of 11.2 more days than the nonbacteremic infants. Vancomycin hydrochloride was given to 20 (52.6%) of the bacteremic patients but only 4 (5.3%) of the comparison patients. All of the comparison subjects and 37 of the 38 infants with bacteremia survived. Thus, nosocomial bacteremia with coagulase-negative staphylococci is a late complication of hospitalization that occurs in infants who are already relatively long-term survivors. This bacteremia appears to be associated with substantially longer hospital stay and antibiotic therapy but little, if any, excess mortality.
A barley leaf cDNA library has been screened with two oligonucleotide probes designed to hybridize to conserved sequences in glutamine synthetase (GS) genes from higher plants. Two GS cDNA clones were identified as hybridizing strongly to one or both probes. The larger clone (pcHvGS6) contained a 1.6 kb insert which was shown by primer extension analysis to be an almost full-length cDNA. Both clones were more closely related to cDNAs for the chloroplast form of GS (GS2) from pea and Phaseolus vulgaris than to cDNAs for the cytosolic form (GS1). A sequence identical to an N-terminal sequence determined from a purified preparation of the mature GS2 polypeptide (NH2-XLGPETTGVIQRMQQ) was found in the pcHvGS6-encoded polypeptide at residues 46-61, indicating a pre-sequence of at least 45 amino acids. The pre-sequence has only limited sequence homology to the pre-sequences of pea and P. vulgaris GS2 subunits, but is similarly rich in basic residues and possesses some of the structural features common to the targeting sequences of other chloroplast proteins. The molecular lesions responsible for the GS2-deficient phenotypes of eight photorespiratory mutants of barley were investigated using a gene-specific probe from pcHvGS6 to assay for GS2 mRNA, and an anti-GS antiserum to assay for GS2 protein. Three classes of mutants were identified: class I, in which absence of cross-reacting material was correlated with low or undetectable levels of GS2 mRNA; class II, which had normal or increased levels of GS2 mRNA but very little GS2 protein; and class III, which had significant amounts of GS2 protein but little or no GS2 activity.
Vinzolidine (VZL), a novel, semi-synthetic vinca alkaloid showing evidence of oncolytic activity in phase I/II clinical trials, was studied in six patients for its pharmacokinetic and metabolic behavior. Following i.v. administration of [3H]-VZL at doses of 5, 6.7, and 9 mg/m2, blood and urine samples were collected and analyzed by sample oxidation and HPLC. Following a single i.v. dose, decay of total tritium in plasma was tetraphasic, with a rapid initial t1/2 alpha of 0.044 +/- 0.013 h, followed by a t1/2 beta of 0.54 +/- 0.22 h and a t1/2 gamma of 9.48 +/- 4.89 h; the terminal t1/2 gamma was 219 +/- 57 h. The mean plasma clearance of total tritium was 0.054 +/- 0.044 l.kg/h, and the mean volume of distribution was 14.3 +/- 5.4 l/kg; mean urinary excretion was 13.6% +/- 4.3% of the delivered radioactivity. Qualitative analysis of plasma and urine revealed the predominance of unchanged VZL plus two unidentified metabolites with different elution times. In comparison with oral VZL, as previously reported, i.v. injected VZL showed comparable values with respect to the volume of the central compartment (VC), plasma clearance (Clp), and terminal t1/2 for total tritium. Qualitatively, the metabolites observed in plasma and urine were comparable in number and quantity with values obtained in analyses after oral administration.
Crude extracts of dried leaves of Hyssop officinalis showed strong anti-HIV activity as measured by inhibition of syncytia formation, HIV reverse transcriptase (RT), and p17 and p24 antigen expression, but were non-toxic to the uninfected Molt-3 cells. Ether extracts from direct extraction (Procedure I), after removal of tannins (Procedure II), or from the residue after dialysis of the crude extract (Procedure III), showed good antiviral activity. Methanol extracts, subsequent to ether, chloroform and chloroform ethanol extractions, derived from procedure I or II, but not III, also showed very strong anti-HIV activity. In addition, the residual material after methanol extractions still showed strong activity. Caffeic acid was identified in the ether extract of procedure I by HPLC and UV spectroscopy. Commercial caffeic acid showed good antiviral activity in the RT assay and high to moderate activity in the syncytia assay and the p17 and p24 antigen expression. Tannic acid and gallic acid, common to other teas, could not be identified in our extracts. When commercial products of these two acids were tested in our assay systems, they showed high to moderate activity against HIV-1. Hyssop officinalis extracts contain caffeic acid, unidentified tannins, and possibly a third class of unidentified higher molecular weight compounds that exhibit strong anti-HIV activity, and may be useful in the treatment of patients with AIDS.
Sixty cases (59 patients) of oromandibular reconstruction using vascularized iliac crests were compared with 13 in which radial osteocutaneous flaps were used. These patients were reviewed from the standpoint of cosmetic results and function as well as their operative and postoperative courses. In both groups, the results were generally good. However, revisionary surgery was more frequent in those receiving the iliac crest. This group also had a higher incidence of intraoral wound breakdown and bone exposure. Nevertheless, the sheer size of the iliac crest made it ideal for massive oromandibular defects, just as its natural curvature lent itself to precise replication of the mandible in bone-only reconstructions. Its bulk proved a major obstacle in small composite defects. The radial forearm flap carried thin, pliable, well-vascularized skin that was superior to groin skin for oral lining. Bone gaps of up to 9 cm could be handled with ease, thus making it complementary to the iliac crest over the wide spectrum of mandibular reconstruction.
Motor and sensory function must be assessed during surgery of scoliosis so as to avoid possible damage to the spinal cord. The intraoperative awakening by a specific benzodiazepine antagonist, flumazenil, was studied prospectively in 20 patients (mean age 17 years) undergoing surgery for severe scoliosis. Premedication consisted in 0.02 mg.kg-1 atropine and 0.15 mg.kg-1 midazolam. Anaesthesia was induced with a mean dose of 0.42 +/- 0.1 mg.kg-1 midazolam, 1.6 +/- 0.6 micrograms.kg-1 fentanyl and 0.1 mg.kg-1 pancuronium. Maintenance was obtained with a continuous infusion of 0.22 +/- 0.1 mg.kg-1.h-1 midazolam, 66% nitrous oxide in oxygen, and fentanyl (1.6 +/- 0.5 micrograms.kg-1.h-1). Nitrous oxide and midazolam were respectively stopped 10 and 1 min before giving the antagonist (5 micrograms.kg-1 flumazenil) if required (17 out of the 20 patients). Eye opening occurred a mean 42 +/- 32 s after giving the antagonist. At this time, there was a significant increase in mean arterial blood pressure (+ 11 mmHg) and heart rate (+ 7 b.min-1). Thiopentone, 66% nitrous oxide in oxygen and 0.5% halothane were given to re-induce and maintain anaesthesia for completion of the procedure. The day following surgery, 19 patients were unable to remember the period of intraoperative awakening. One patient, although remembering the episode, did not experience any pain or any other disagreement in relation to it. Two patients were given a second dose of flumazenil at extubation so as to improve the quality of their recovery.(ABSTRACT TRUNCATED AT 250 WORDS)
Forty-three intubated and mechanically ventilated patients in five intensive care units (ICUs) of one hospital developed respiratory colonization or infection with Acinetobacter calcoaceticus subspecies anitratus over a 16-month interval. Neither the frequency nor rate of A anitratus isolation exceeded the hospital endemic norms. Single isolates from 34 of the patients were subtyped by plasmid DNA analysis, two biotyping systems and antimicrobial susceptibility to 24 drugs. Plasmid DNA fingerprints were distinct in 18 isolates (they differed from each other and all others), similar in two and identical or similar in ten. The latter group of isolates were recovered from patients in four ICUs. Reproducibility of biotyping was poor. Neither biotyping nor antimicrobial susceptibility were successful in identifying sameness among the group isolates nor differences among other isolates. We conclude that plasmid DNA fingerprinting should be used to assess the possibility of multiple patient transmissions of the same A anitratus strain in the absence of an obvious outbreak.
Coagulase-negative staphylococci are the most common cause of bacteremia in the neonatal intensive care units of the Brigham and Women's Hospital and the Children's Hospital, Boston, Massachusetts. In 1982, nosocomial bacteremia with coagulase-negative staphylococci occurred in 45 of 882 (5.1%) infants admitted to these units who survived and remained in intensive care for more than 48 hours and were therefore at risk. The overall cumulative incidence (attack rate) of nosocomial bacteremia rose dramatically with decreasing birth weight. The smallest infants, those with birth weights of less than 750 g, experienced an overall risk of nosocomial bacteremia 44.5 times that of infants with birth weights of greater than 2,000 g. A large part of the excess risk for small babies was attributable to their longer hospitalizations. However, after adjustment for length of stay, the smallest infants still suffered a daily rate of bacteremia (incidence density) 5.3 times that of the largest, indicating a considerable residual effect of birth weight on the daily risk of nosocomial coagulase-negative staphylococcal bacteremia. The results were similar in the two nurseries. Thus, there is still a substantially increased intrinsic risk of nosocomial coagulase-negative staphylococcal bacteremia among infants with very low birth weights, even after adjustment for duration of hospitalization, and differences in birth weight can confound comparative studies.
The gln-gamma gene, encoding the gamma subunit of glutamine synthetase in French bean (Phaseolus vulgaris), is strongly induced during nodule development. We have determined the nucleotide sequence of a 1.3-kilobase region at its 5' end and have identified several sequences common to the promoter regions of late nodulin genes from other legume species. The 5'-flanking region was analyzed for sequence-specific interactions with nuclear factors from French bean. A factor from nodules (PNF-1) was identified that binds to multiple sites between -860 and -154, and a related but distinct factor (PRF-1) was detected in extracts from uninfected roots. PNF-1 and PRF-1 bound strongly to a synthetic oligonucleotide containing the sequence of an A/T-rich 21-base pair imperfect repeat found at positions -516 and -466. The same factors also had a high affinity for a protein binding site from a soybean leghemoglobin gene and appeared to be closely related to the soybean nodule factor NAT2, which binds to A/T-rich sequences in the lbc3 and nodulin 23 genes [Jacobsen et al. (1990). Plant Cell 2, 85-94]. Comparison of NAT2/PNF-1 binding sites from a variety of nodulin genes revealed the conservation of the short consensus core motif TATTTWAT, and evidence was obtained that this sequence is important for protein recognition. Cross-recognition by PNF-1 of a protein binding site in a soybean seed protein gene points to the existence of a ubiquitous family of factors with related binding affinities. Our data suggest that PNF-1 and PRF-1 belong to an evolutionarily conserved group of nuclear factors that interact with specific A/T-rich sequences in a diverse set of plant genes. We consider the possible role of these factors in coregulating the expression of gln-gamma and other late nodulin genes.
Electrode grids were implanted subdurally in 28 patients with epilepsy. In 16 of the 28 patients, an epileptogenic area was located in the speech-dominant left temporal lobe. Recordings made with the grid revealed that the epileptogenic areas in the patients varied widely in extent: the area was confined within the first 10 mm of the temporal lobe in some patients or it was scattered throughout the entire anterior to posterior 80-mm extend in others. Resection of the epileptogenic area was adjusted accordingly in each case. In 6 of 16 patients who were left-hemisphere-dominant for language, up to 55-80 mm from the tip of the temporal lobe was removed, a measure that exceeds the conventional limit of 50 mm from the tip of the dominant hemisphere. In the remaining 12 of the 28 patients, epileptogenic areas were located in a combination of several lobes. In 7 of these 12 patients, the epileptogenic area encompassed the rolandic area; it was removed without deficit in 4 patients and with expected deficit in 3. Of the latter 3 patients, 1 patient underwent hemispherectomy, and a large portion of the epileptogenic rolandic cortex in the frontal and parietal lobes was removed from the other 2. There were 2 cases of grid-related infection, which cleared with antibiotic treatment; there were no lasting complications of grid implantation in any patient. There was no mortality. Electroencephalographic recording and functional mapping using subdural electrode grids allow a tailored, maximal resection of epileptogenic tissue with minimal injury to critical cortex.
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