The use of a single von Willebrand factor-containing, plasma-derived FVIII product in hemophilia A immune tolerance induction: the US experience

BACKGROUND

Inhibitors are a serious complication for patients with severe hemophilia A. Immune tolerance induction (ITI) is the primary method for eradicating these inhibitors. The role of type of concentrate and in particular the use of von Willebrand factor-containing, plasma-derived factor VIII (VWF/pd-FVIII) concentrate in primary or rescue ITI remains unclear.

OBJECTIVES

To report retrospective collection of data on the use of a single VWF/pd-FVIII concentrate in primary and rescue ITI.

METHODS

Retrospective chart review of hemophilia A inhibitor patients at 11 US institutions who received VWF/pd-FVIII concentrate in primary or rescue ITI.

RESULTS

Primary ITI was carried out in eight inhibitor patients with a 75% complete and partial success. Secondary ITI was carried out in 25 inhibitor patients, with 52% attaining complete or partial success.

CONCLUSIONS

This report represents the largest group of primarily pediatric, high-titer inhibitor patients treated with a single VWF/pd-FVIII concentrate. It adds retrospective data to the use of VWF-containing plasma-derived factor VIII concentrate in primary and rescue ITI, particularly in those patients with characteristics of poor response to ITI.

Evaluation of the safety and efficacy of pathotropic nanoparticles bearing a dominant negative cyclin G1 construct for chemoresistant osteosarcoma and other sarcomas: Phase I, II, and III studies

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Background: (1) To evaluate the safety/anti-tumor potential of intravenous (i.v.) Rexin-G in chemotherapy-resistant sarcoma (Phase I/II), and (2) to confirm the efficacy/safety of i.v. Rexin-G in chemotherapy-resistant osteosarcoma (Phase II). Methods: Twenty patients in the Phase I/II study and 22 patients in the Phase II study received 1–2 × 10e11 cfu Rexin-G i.v., 2–3 times a week for 4 weeks. Treatment was continued if the patient had < Grade 1 toxicity. Results: Treatment-related adverse events included chills (n=1), presyncope (n=1), photophobia (n=1) of Grade 1 severity, and fatigue (n=4) of Grade 1–2 severity. In the Phase I/II sarcoma study, 3/6 patients had stable disease at Dose Level 0, median progression free survival (PFS) was 5 weeks, and overall survival (OS) was 14 weeks, while 10/14 patients had stable disease at Dose Level I-II, median PFS was 16 weeks and median OS was 34 weeks. Cox regression analysis showed a dose-response relationship between PFS/OS and Rexin-G dosage (p = 0.02 and 0.005, respectively). The Table below shows the results for evaluable patients (n=17) in the Phase II study for osteosarcoma. Kaplan-Meier analysis shows a dose-response relationship between overall survival and Rexin-G dosage in the combined Phase I/II sarcoma and Phase II osteosarcoma studies (p = 0.02; n=42). Two patients achieved surgical remissions which are sustained for >26 weeks. Conclusions: These studies suggest that (i) intravenous Rexin-G is safe and well-tolerated, and (ii) Rexin-G controls tumor growth and prolongs progression-free survival and overall survival in a dose-dependent manner in chemotherapy-resistant osteosarcoma and sarcoma. [Table: see text]

[Table: see text]

Processing of beta-amyloid precursor protein by cathepsin D

The events leading to the formation of beta-amyloid (betaA4) from its precursor (betaAPP) involve proteolytic cleavages that produce the amino and carboxyl termini of betaA4. The enzyme activities responsible for these cleavages have been termed beta- and gamma-secretase, respectively, although these protease(s) have not been identified. Since betaA4 is known to possess heterogeneity at both the amino and carboxyl termini, beta- and gamma-secretases may actually be a collection of proteolytic activities or perhaps a single proteolytic enzyme with broad amino acid specificity. We investigated the role of cathepsin D in the processing of betaAPP since this enzyme has been widely proposed as a gamma-secretase candidate. Treatment of a synthetic peptide that spans the gamma-secretase site of betaAPP with human cathepsin D resulted in the cleavage of this substrate at Ala42-Thr43. A sensitive liquid chromatography/mass spectrometry technique was also developed to further investigate the ability of cathepsin D to process longer recombinant betaAPP substrates (156 and 100 amino acids of betaAPP carboxyl terminus) in vitro. The precise cathepsin D cleavage sites within these recombinant betaAPP substrates were identified using this technique. Both recombinant substrates were cleaved at the following sites: Leu49-Val50, Asp68-Ala69, Phe93-Phe94. No cleavages were observed at putative gamma-secretase sites: Val40-Ile41 or Ala42-Thr43, suggesting that cathepsin D is not gamma-secretase as defined by these betaA4 termini. Under conditions where the betaAPP156 substrate was first denatured prior to cathepsin D digestion, two additional cleavage sites near the amino terminus of betaA4, Glu-3-Val-2 and Glu3-Phe4, were observed, indicating that cathepsin D cleavage of betaAPP is influenced by the structural integrity of the substrate. Taken together, these results indicate that in vitro, cathepsin D is unlikely to function as gamma-secretase; however, the ability of this enzyme to efficiently cleave betaAPP substrates at nonamyloidogenic sites within the molecule may reflect a role in betaAPP catabolism.

Early Alzheimer disease-like histopathology increases in frequency with age in mice transgenic for beta-APP751

beta-Amyloid deposition and neurofibrillary tangle formation are two histopathological features of Alzheimer disease. We have previously reported that beta-amyloid immunoreactive deposits form in the brains of transgenic mice programmed for neuronal expression of the 751-amino acid isoform of human beta-amyloid precursor protein (beta-APP751) and now describe that these animals also display Alz50 intraneuronal immunoreactivity similar to that seen in early Alzheimer disease. This suggests that abnormal beta-APP expression and/or beta-amyloid deposition promotes pathogenic alterations in tau protein. The frequency of both beta-amyloid deposition and Alz50-positive neurons was twice as prevalent in brains from old (22 months) as compared to young (2-3 months) beta-APP751 transgenic mice. This increase in histopathology with age in beta-APP751 transgenic mice parallels the time-dependent progression seen in the human disease.

Inhibition of beta-amyloid formation identifies proteolytic precursors and subcellular site of catabolism

Cerebral deposition of beta-amyloid protein is a pathological feature central to Alzheimer's disease. Production of beta-amyloid by proteolytic processing of the beta-amyloid precursor protein (beta APP) is a critical initial step in beta-amyloidogenesis. We use an inhibitor of beta APP processing to block beta-amyloid peptide formation. Application of the inhibitor to cultured cells results in an accumulation of proteolytic intermediates of beta APP, enabling a precursor-product relationship between beta APP carboxy-terminal fragments and beta-amyloid peptides to be demonstrated directly. In the presence of inhibitor, these amyloidogenic carboxy-terminal fragments can be degraded to nonamyloidogenic products. The catabolism of beta APP carboxy-terminal intermediates and the formation of beta-amyloid peptides are likely to involve an early endosomal compartment as the subcellular site of processing.

beta-Amyloid peptide produced in vitro is degraded by proteinases released by cultured cells

The primary histopathological feature of Alzheimer's disease is the accumulation of beta-amyloid in the brains of afflicted individuals. This peptide has been shown to be produced and liberated both in vitro and in vivo by normal physiological processes. The mechanism by which beta-amyloid is formed, as well as that by which it may be cleared, are events likely to impact on the development and progression of this disease. Thus, the fate of beta-amyloid peptides secreted by cultured mammalian cells was investigated. It was found that levels of the soluble peptide are reduced over time due to the activity of multiple types of proteinases including those from the metallo, aspartyl, and thiol classes. Inhibitors to each class of proteinase can only partially block beta-amyloid degradation, but, if used in combination, they can fully prevent its catabolism. The Kunitz serine proteinase inhibitor domain, present on two beta-amyloid precursor protein isoforms, was found to be an effective inhibitor of beta-amyloid peptide degradation. These data indicate that modulations in expression of secreted proteinases and/or beta-amyloid precursor isoforms may influence levels of beta-amyloid.

Increased amyloid production from aberrant beta-amyloid precursor proteins

The 4-kDa beta-amyloid protein that forms fibrillar deposits in Alzheimer's diseased brains is derived from a large precursor, the beta-amyloid precursor protein (beta-APP). Recently, it has been reported that beta-amyloid is normally produced and secreted by cultured mammalian cells. In our studies involving recombinant expression of beta-APP, increased yields of beta-amyloid were associated with expression of aberrant beta-APP molecules. Deletion mutations within the beta-amyloid domain, incorrect beta-APP isoform expression in fibroblasts or neuronal cells, or excess amounts of beta-APP all led to increases in beta-amyloid production. Aberrant beta-APP appears to be diverted from the secretory pathway and then degraded to beta-amyloid.

Multinodular versus plexiform neurilemoma of the hard palate. Report of a case

Neurilemoma (schwannoma) is the most commonly encountered nerve sheath tumor of the oral cavity. It generally appears as a single encapsulated nodule that occasionally causes pain or discomfort. The tongue is involved most frequently, followed by the palate, floor of mouth, and buccal mucosa. Neurilemomas occur most often during the second or third decades of life. Our patient is a 21-year-old woman with a recurrence of a palatal mass that was excised 3 years earlier. Histologically the lesion appeared to be a multinodular neurilemoma, a pattern rarely reported in the oral cavity.

Secretion of beta-amyloid precursor protein involves multiple cleavage sites

A major histopathological feature of Alzheimer's disease is deposits of a approximately 4-kDa beta-amyloid peptide derived by proteolytic processing from a precursor, the beta-amyloid precursor protein (beta-APP). Proteolytic cleavage of beta-APP within the approximately 4-kDa beta-amyloid domain permits the secretion of the amino-terminal portion of beta-APP while concomitantly producing a membrane bound approximately 9-kDa carboxyl-terminal fragment. We have characterized the proteolytic cleavage site for beta-APP secretion by amino acid sequence analysis of the approximately 9-kDa beta-APP carboxyl-terminal cleavage product produced by recombinant and native expression systems. Recombinant beta-APP was generated by a vaccinia virus expression system in CV-1 monkey fibroblasts; endogenous beta-APP was obtained using a fibroblast line derived from an individual with Down's syndrome. The sequences of both unlabeled and metabolically radiolabeled approximately 9-kDa fragment from CV-1 cells reveal that the major (60%) secretory cleavage site is after Lys16 of the beta-amyloid domain as reported previously; however, an additional cleavage site is seen after Phe19 (40%). Radiosequence analysis of the carboxyl-terminal fragment purified from Down's syndrome fibroblasts indicates cleavage sites after Phe19, Glu22, and Gly25 and not after Lys16. CV-1 cells expressing beta-APP mutants lacking 4 and 6 amino acids adjacent to Lys16 yielded approximately 9-kDa fragments with two identical cleavage sites, neither of which occurred after the retained Lys16 but were after Glu11 and His13. These data suggest that secretion of beta-APP involves multiple proteinases and that the composition of these proteinases may vary within different cell backgrounds.

Transgenic mice expressing human beta-APP751, but not mice expressing beta-APP695, display early Alzheimer's disease-like histopathology

Mice transgenic for the 751 amino acid isoform of the human beta-amyloid precursor protein (beta-APP) driven by the rat neuron specific enolase (NSE) promoter (NSE:beta-APP751) show features of early Alzheimer's disease (AD) pathology. These features, which were evident in multiple pedigrees, include: 1) preamyloid deposits which stain with antibodies that are specific for the beta-amyloid peptide and stain AD amyloid deposits and plaques, and 2) neuronal soma and processes which stain with an antibody (Alz50) that detects abnormal isoforms of tau which are characteristic of AD. The quality and distribution of both types of immunoreactivity revealed in the NSE:beta-APP751 mouse brains most closely resemble those seen in brains of young adults with Down's syndrome. Both structures are rarely, if ever, observed in brains from mice transgenic for the 695 amino acid isoform of beta-APP (NSE:beta-APP695) or in wild type mice.

Mapping of multiple mouse loci related to the farnesyl pyrophosphate synthetase gene

The prenyltransferases are a class of enzymes involved in the synthesis of sterol and nonsterol isoprene compounds. We report here the chromosomal mapping of nine loci in the mouse that hybridize to the cDNA for the enzyme farnesyl pyrophosphate synthetase (FPS), a prenyltransferase that catalyzes the synthesis of an intermediate common to both the sterol and nonsterol branches of the isoprene biosynthetic pathway. Mapping was performed with genomic DNA from a mouse-hamster somatic cell hybrid panel, and by linkage analysis with recombinant inbred strains and the progeny of an interspecific backcross. The mapped loci have been designated farnesyl pyrophosphate synthetase-like-1 (Fpsl-1) on mouse Chromosome (Chr) 3; Fpsl-2 on Chr 4; Fpsl-3, Fpsl-4, and Fpsl-5, dispersed on Chr 10; Fpsl-6 on Chr 12; Fpsl-7 on Chr 13; Fpsl-8 on Chr 17; and Fpsl-9 on Chr X. It is presently unclear which of these loci encode active prenyltransferases and which may correspond to pseudogenes. The strongly hybridizing loci provide convenient genetic markers for seven mouse chromosomes.

Ciliary neurotrophic factor prevents neuronal degeneration and promotes low affinity NGF receptor expression in the adult rat CNS

Recombinant human ciliary neurotrophic factor (CNTF) was infused for 2 weeks into the lateral ventricle of fimbria-fornix transected adult rats, and its effects were compared with those of purified mouse nerve growth factor (NGF). We provide evidence that CNTF can prevent degeneration and atrophy of almost all injured medial septum neurons (whereas NGF protects only the cholinergic ones). CNTF is also involved in up-regulation of immunostainable low affinity NGF receptor (LNGFR) in cholinergic medial septum and neostriatal neurons and in a population of lateral septum neurons. In contrast to NGF, CNTF did not stimulate choline acetyltransferase in the lesioned septum and normal neostriatum (pointing to different mechanisms for the regulation of choline acetyltransferase and LNGFR), cause hypertrophy of septal or neostriatal cholinergic neurons, or cause sprouting of LNGFR-positive (cholinergic) septal fibers.

Formation of beta-amyloid protein deposits in brains of transgenic mice

Deposits of beta-amyloid are one of the main pathological characteristics of Alzheimer's disease. The beta-amyloid peptide constituent (relative molecular mass 4,200) of the deposits is derived from the beta-amyloid precursor protein (beta-APP) which is expressed in several different isoforms. The two most prevalent beta-APP isoforms are distinguished by either the presence (beta-APP751) or absence (beta-APP695) of a Kunitz serine protease inhibitor domain. Changes in the abundance of different beta-APP messenger RNAs in brains of Alzheimer's disease victims have been widely reported. Although these results have been controversial, most evidence favours an increase in the mRNAs encoding protease inhibitor-containing isoforms of beta-APP and it is proposed that this change contributes to beta-amyloid formation. We have now produced an imbalance in the normal neuronal ratio of beta-APP isoforms by preparing transgenic mice expressing additional beta-APP751 under the control of a neural-specific promoter. The cortical and hippocampal brain regions of the transgenic mice display extracellular beta-amyloid immunoreactive deposits varying in size (less than 5-50 microns) and abundance. These results suggest that one mechanism of beta-amyloid formation may involve a disruption of the normal ratio of neuronal beta-APP isoform expression and support a direct relationship between increased expression of Kunitz inhibitor-bearing beta-APP isoforms and beta-amyloid deposition.

Identification and characterization of C-terminal fragments of the beta-amyloid precursor produced in cell culture

The mechanism of amyloid formation in Alzheimer's disease is unknown but appears to involve proteolytic processing of the amyloidogenic peptide from a larger precursor. When the C-terminus containing the amyloid-forming and cytoplasmic domains of the precursor was recombinantly expressed in cultured mammalian cells, a 16 kd protein accumulated which had a tendency to aggregate and form deposits. These deposits had physical characteristics resembling those of preamyloid. Recombinant expression of the full-length precursor was found to produce a similar, cell-associated 16 kd C-terminal fragment as well as a 12 kd fragment, neither of which formed detectable aggregates suggesting efficient catabolism of these fragments. Identification of these two naturally occurring metabolic products of the beta-amyloid precursor provides a system permitting the characterization of the proteolytic processing events of the amyloid precursor protein.

Fibroblast growth factor induces beta-amyloid precursor mRNA in glial but not neuronal cultured cells

Treatment of PC12 and C6 cell cultures with recombinant basic fibroblast growth factor results in approximately a five to ten-fold stimulation of beta-amyloid precursor mRNA in the C6 astrocytoma cell line but only a slight induction of precursor mRNA in the PC-12 neuronal cell line. Stimulation of expression occurred at a hormone concentration of approximately 0.5 to 1 nM and was seen after 2 days. These results suggest that basic fibroblast growth factor may contribute to amyloidosis of Alzheimer's disease.

A method of stereoptically simulating manifolds of three-dimensional objects using only a single display pattern: a shape-depth-texture invariance

A means of conceptualizing and generating visual displays that are "self-stereoptic manifolds" is described. First, single patterns that can replace pairs of stereograms to produce illusions of depth are defined and an example is shown. Patterns such as these produce illusory three-dimensional objects hanging in space before or behind the display surface. It is further demonstrated geometrically that such a display actually has three-dimensional information embedded in it peculiar to each of a family, or manifold, of objects that can be experienced one at a time. Each object of the family appears when the viewer looks in space where it "exists." The others remain invisible unless their locations are fixated. If any member of a specific manifold of three-dimensional illusory objects is physically duplicated as a real object and textured in the same way that the illusory object appeared to be, then this new real object will, in turn, generate an illusion of each of the other objects of the manifold when the observer fixates in space where each "exist." Also, if then the viewer looks where the original display previously was, the newly constructed object will disappear and the display will reappear. The geometry and the advantages and disadvantages in relation to a stereoptic pair are discussed.

Pulmonary function testing in predicting complications from percutaneous lung biopsy

Percutaneous needle biopsy is an accepted method of obtaining tissue for diagnosis of lung tumors. The depth of the lesion, size of the needle, operator experience, and the presence of emphysema have been identified as factors influencing the risk of postbiopsy pneumothorax, the most common complication. In this retrospective study of 308 patients, we enquired whether pulmonary function tests (available in 138 patients) and arterial PO2 (available in 103 patients) might predict the risk of pneumothorax following percutaneous needle biopsy. We found that as airway obstruction increases (FEV1.0/FVC less than 59% of predicted) or as arterial oxygenation decreases (PO2 less than 59 mm Hg), not only does the incidence of pneumothorax increase, but symptoms are more severe in that the number of pneumothoraces requiring chest tube drainage increases as well. We suggest that airway obstruction and arterial oxygenation are factors indicative of increased risk identifying patients who need close scrutiny after the procedure.

Radiographic and sonographic findings in spontaneous retrograde intussusception

Spontaneous retrograde intussusception causing obstruction is rare. We describe the radiographic and sonographic appearances, which should have been sufficient for preoperative diagnosis, in one patient.

Genetic factors controlling structure and expression of apolipoproteins B and E in mice

We report the identification and partial characterization of polymorphisms among inbred strains of mice affecting several aspects of the expression of apolipoproteins B and E (apoB and apoE), the major proteins of low density lipoproteins (LDL) and very low density lipoproteins (VLDL). These polymorphisms include differences in the levels of the lipoproteins and apolipoproteins on both chow and high fat diets, differences in their response to a high fat diet challenge, and differences in the relative levels of the two molecular weight species of apoB. Although most strains exhibited a large increase in plasma LDL and VLDL in response to a high fat diet, the levels of apoB and apoE mRNA were either unaffected or, in some cases, decreased slightly. Also, the levels of apoB and apoE mRNA were not correlated among strains with the levels of the apolipoproteins in plasma, suggesting that genetic control occurs primarily at the level of lipoprotein catabolism. Elucidation of the precise mechanisms involved in the differences will require genetic analysis. Toward this end, we have identified DNA polymorphisms for apoB and apoE and have used these in segregation analysis to determine the chromosomal locations of the apoB and apoE structural genes in mice. The gene for apoB, designated Apob, resides in the proximal region of chromosome 12 linked to genes for ribosomal RNA and aryl hydrocarbon hydroxylase. The gene for apoE, designated Apoe, is located on chromosome 7, linked to genes for glucose phosphate isomerase and peptidase 4. Previously, we mapped the structural genes for apolipoproteins A-I and A-II to mouse chromosomes 9 and 1, respectively, and thus, the four loci encoding mammalian apolipoproteins have now been located in the mouse. These loci are homologous to the loci encoding apolipoproteins in humans as judged by the conservation of linked markers. A correlation was observed between a unique apoB allele and "responsiveness" to a high fat diet challenge. There were no obvious associations of apoB, apoE, or LDL/VLDL phenotypes or genotypes with diet-induced atherosclerosis among strains surveyed. These results clarify the organization and regulation of the genes for apoB and apoE, and they provide information about the naturally occurring polymorphisms affecting their expression.

Quantitative concepts in avoiding intraocular lens damage from the Nd:YAG laser in posterior capsulotomy

Damage to the intraocular lens (IOL) in Nd:YAG laser posterior capsulotomy is a complication to be avoided. The damage threshold for many of the commercially available IOLs was determined. The power density at the focal point was calculated for FDA approved Nd:YAG lasers. Based on the therapeutic gap concept it is recommended that only power levels below the damage threshold be used in photodiscission posterior capsulotomy to minimize the risk of Nd:YAG laser IOL damage.

Perception of orientation of motion as affected by change in divergence of texture, change in size, and in velocity

When there is relative motion between an observer and a textured surface such as the ground, motion-related visual information is available about the orientation of the surface through vergence of the paths of the elements of the texture, change in their sizes and in their velocities. This experiment determined the perceptual effectiveness of each variable in foveal and peripheral viewing for producing perceptions of three-dimensional motion. The three variables were electronically separated and displayed singly, in all possible pairs, and all together. Subjects communicated their perceptions of degree of perceived surface tilt at the top, bottom, and middle of the display for the eight different combinations of variables because, during pilot work perceived surface bendings were frequently noted where top, bottom, and middle appeared tilted to different extents. All three variables can lead to relatively reliable perceptions of perceived orientation of the plane of motion, with change in velocity being the most powerful determiner. Change in size was the weakest. Certain combinations can lead to perceptions of extreme warping and should be avoided in motion displays. Subjects consistently underestimate the amount of simulated tilt. Foveal viewing was more accurate than peripheral viewing but peripheral performance was adequately consistent as an input channel for some orientation tasks.

The inadvertent CT demonstration of intussusception

We report a patient with idiopathic ceco-colic intussusception diagnosed by computed tomography (CT). Due to an unusual set of circumstances, the accepted algorithm of diagnostic investigations was not followed. This led to the inadvertent CT demonstration of an intussusception in an adult as a thick-walled mass containing a multiplicity of barium and gas-filled loops.

The linkage arrangement of four rabbit beta-like globin genes

Four different regions of rabbit beta-like globin gene sequences designated beta 1, beta 2, beta 3 and beta 4 were identified in a set of clones isolated from a bacteriophage lambda library of chromosomal DNA fragments (Maniatis et al., 1978). Restriction mapping and blot hybridization (Southern, 1975) studies indicate that a subset of these clones containing beta 1 and beta 2 hybridizes to an adult beta-globin cDNA clone (Maniatis et al., 1976) more efficiently than to a human gamma-globin cDNA clone (Wilson et al., 1978), while another subset containing beta 3 and beta 4 displays the converse hybridization specificity. beta 1 was identified as the adult beta-globin gene, while beta 2, beta 3 and beta 4 have not been identified with any known rabbit globin polypeptides. Cross-hybridization and transcriptional orientation experiments indicate that the set of beta-like gene clones contains overlapping restriction fragments encompassing 44 kb of rabbit chromosomal DNA. In addition, all four genes have the same transcriptional orientation and are arranged in the order 5'-beta 4-beta 3-beta 2-beta 1-3'.

The isolation of structural genes from libraries of eucaryotic DNA

We present a procedure for eucaryotic structural gene isolation which involves the construction and screening of cloned libraries of genomic DNA. Large random DNA fragments are joined to phage lambda vectors by using synthetic DNA linkers. The recombinant molecules are packaged into viable phage particles in vitro and amplified to establish a permanent library. We isolated structural genes together with their associated sequences from three libraries constructed from Drosophila, silkmoth and rabbit genomic DNA. In particular, we obtained a large number of phage recombinants bearing the chorion gene sequence from the silkmoth library and several independent clones of beta-globin genes from the rabbit library. Restriction mapping and hybridization studies reveal the presence of closely linked beta-globin genes.

THE VAPOR PHASE PARTIAL OXIDATION OF n-BUTANE—EFFECT OF PRESSURE, REACTION TIME, AND INLET GAS COMPOSITION

Data are presented on the product yields and the general course of the partial oxidation of n-butane at an ambient temperature of 725 °F., at pressures ranging from 50 to 175 p.s.i.a., reaction times of 1.0 to 4.5 sec., and inlet reactant compositions of 1.5 to 6.0 mole % n-butane and 1.5 to 6.0 mole % oxygen (the remainder being diluent nitrogen). Conditions were neither isothermal nor adiabatic and peak temperatures as much as 70 Fahrenheit degrees higher than the inlet temperatures were encountered. The reactor consisted of a 24-ft. length of 1/4-in. stainless steel pipe, immersed in a bath of boiling Aroclor 1254. Under optimum conditions, a 20% conversion of the butane to methanol, ethanol, acetaldehyde, acetone, and formaldehyde was obtained. In all the tests, an induction period of approximately 0.75 sec. was observed.