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W Hudson

Publications and source records attributed to W Hudson.

10 recordsLinked to original sources
PubMed2001

Observations on the distribution and control of Salmonella species in two integrated broiler companies.

The effectiveness of cleaning and disinfecting broiler farms and the persistence of Salmonella species in two integrated broiler companies was investigated for two years. Both companies used a cleaning and disinfection regime which included the application of a spray of phenolic disinfectant followed by fogging with formaldehyde solution, and this was highly effective in preventing carry-over of infection in the broiler houses. The disinfection of service areas and areas outside the houses was less effective but it had no influence on the Salmonella status of later flocks. Both companies had persistent problems with the contamination of pellet cooling systems in their feedmills with Salmonella 4, 12:d:- in company A, and with Salmonella binza and Salmonella ohio in company B. The hatcher incubators of both companies were also persistently contaminated with Salmonella livingstone and Salmonella thomasville in company A and with Salmonella senftenberg in company B. At both companies sites Salmonella enteritidis and Salmonella typhimurium Tr104 were also isolated occasionally from various locations.

Animals↗
PubMed1998

Pharmacokinetics and biodistribution of radioimmunoconjugates of anti-CD19 antibody and single-chain Fv for treatment of human B-cell malignancy.

The comparative advantages and disadvantages of intact antibodies and single-chain Fv as immunotoxins and radioimmunoconjugates have been widely discussed but not directly compared. In this study, the in vivo properties of anti-CD19 B43 monoclonal antibody and its derived single-chain Fv (FVS191) were studied in athymic nude mice bearing CD19-positive human lymphomas. B43 mab and FVS191 were labeled with iodine-125 using iodine-beads, and immunoreactivities were determined to be 57% and 72%, respectively. Scatchard analysis showed a similar high affinity for both. The results of pharmacokinetic studies revealed that FVS191 had a rapid biphasic clearance from the circulation (T1/2alpha=2.5 min, T1/2beta=3.7 h); The T1/2alpha and T1/2beta phases of B43 mab were determined to be 0.72 h and 57 h respectively. Biodistribution studies compared the uptake of labeled antibodies by CD19-positive and by CD19-negative tumors. The peak percentages of injected dose were 5.7% at 12 h for B43 and 2.45% at 1 h for FVS191. Radiolocalization indices (RI) demonstrated tumor-specific uptake for both, but higher uptake for B43. The optimal RI was seen at 15 min for FVS191 and 6 h for B43. FVS191 was unstable in vivo, approximately 50% of the injected dose being degraded in blood in 100 min. Radioactivity detected in the urine was present mainly as the deiodinized form of FVS191. The results suggest that B43 mab is favored over FVS191 in biodistribution properties and in vivo stability. Because B43 Mab showed early tumor-specific uptake, high RI values, and favorable tissue-to-blood ratios, it is a potential candidate for radioimmunotherapy and immunotoxin therapy of B-cell leukemia and lymphoma.

Animals↗
PubMed1994

An adaptive algorithm for the automatic segmentation of continuous stuttered speech.

This paper presents an adaptive algorithm for the automatic segmentation of continuous speech into voiced, unvoiced, and silence regions (V/U/S). The procedure presented is based on the use of a digital filter bank with control parameters established using formant frequencies of voiced segments of speech. This procedure makes it possible to separate continuous speech into syllable like structures. The use of these speech segments makes possible the determination of stuttered speech. Special care is given to the handling of prolongations and repetitions (audible and silent) to insure they are properly handled by the segmenting algorithm. Segmentation experiments have been conducted on male and female subjects to test the reliability of the system at segmenting fluent and stuttered continuous speech.

Algorithms↗
PubMed1986

Spontaneous CSF otorrhea from tegmen and posterior fossa defects.

Spontaneous cerebrospinal otorrhea (SCSFO) from tegmen or posterior fossa defects is uncommon. Twenty-nine cases have been detailed in the literature to date. We report an additional four cases from three patients. This group of 33 cases of SCSFO from tegmen or posterior fossa defects is characterized by certain clinical features. These patients are usually older adults (mean age 48 years, range 8 months to 80 years). Aural fullness with a serous appearing middle ear effusion, or clear otorrhea, often subsequent to tube myringotomy, are the usual initial symptoms. Meningitis was the initial manifestation in eight patients (24%), and ultimately occurred in an additional four patients (12%). The pathophysiologic basis for SCSFO from tegmen defects is discussed. Methods for diagnosing and treating CSF otorrhea from tegmen defects are reviewed.

Adolescent↗
PubMed1975

Misuse of analysis of covariance in aging research and some partial solutions.

Gerontological researchers are reminded of the inappropriateness of analysis of covariance wherein the covariate is correlated with the independent variable, typically age. Two partial solutions are suggested that deal with the confounding of age effects with such uncontrolled variables as, for example, initial ability level or level of education.

Adult↗
PubMedDate not supplied

Generation and characterization of an anti-CD19 single-chain Fv immunotoxin composed of C-terminal disulfide-linked dgRTA.

Our laboratory utilized two methods to produce the anti-CD19 immunotoxin containing a single-chain Fv (scFv) FVS191 and a ricin A chain (RTA). The first method produced the recombinant protein FVS191CDRTA from a fusing gene containing sequences encoding FVS191, catheptsin D proteinase digestion site (CD), and RTA. FVS191CDRTA did not show CD19 antigen binding and cytotoxic activity. The second method generated a disulfide-linked FVS191cys-dgRTA from a FVS191cys, the FVS191 with an additional C-terminal cysteine, and a deglycosylated RTA (dgRTA). The formation of FVS191cys-dgRTA is efficient; up to 70% of the proteins participating in the reaction had formed FVS191cys-dgRTA when the molar ratio of FVS191cys to dgRTA was 1:1. A competitive ELISA assay indicated that FVS191cys-dgRTA and the parental monoclonal antibody B43 possessed comparable CD19 binding abilities. The protein synthesis inhibition assay revealed that FVS191cys-dgRTA was toxic to CD19 positive cell lines, but it was less potent than the intact antibody-conjugated B43-dgRTA, which had an IC50 = 2 x 10(-11) M. 125I-Labeled FVS191 and 125I-labeled B43 were internalized by Nalm-6 cells at 37 degrees C as demonstrated by internalization studies; this result indicates that cross-linking of CD19 antigen is not required for the endocytosis of CD19 and raises the possibility that the lower cytotoxity of FVS191cys-dgRTA is not due to the monovalent binding of CD19 by FVS191cys-dgRTA. Our study with anti-CD19 scFv immunotoxin indicates that the formation of a disulfide-linked scFv immunotoxin is an alternative to the recombinant method of producing scFv immunotoxin.

Antigens, CD19↗