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W Roberts

Publications and source records attributed to W Roberts.

At least 19 recordsLinked to original sources
PubMed1997

Personal references.

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Computer Communication Networks↗
PubMed1997

Expression of the human milk protein beta-casein in transgenic potato plants.

A 1177 bp cDNA fragment encoding the human milk protein beta-casein was introduced into Solanum tuberosum cells under control of the auxin-inducible, bidirectional mannopine synthase (mas1',2') promoters using Agrobacterium tumefaciens-mediated leaf disc transformation methods. Antibiotic-resistant plants were regenerated and transformants selected based on luciferase activity carried by the expression vector containing the human beta-casein cDNA. The presence of human beta-casein cDNA in the plant genome was detected by PCR and DNA hybridization experiments. Human beta-casein mRNA was identified in leaf tissues of transgenic plants by RT-PCR analysis. Human beta-casein was identified in auxin-induced leaf and tuber tissues of transformed potato plants by immunoprecipitation and immunoblot analysis. Human beta-casein produced in transgenic plants migrated in polyacrylamide gels as a single band with an approximate molecular mass of 30 kDa. Immunoblot experiments identified approximately 0.01% of the total soluble protein of transgenic potato leaf tissue as beta-casein. The above experiments demonstrate the expression of human milk beta-casein as part of an edible food plant. These findings open the way for reconstitution of human milk in edible plants for replacement of bovine milk in baby foods for general improvement of infant nutrition, and for prevention of gastric and intestinal diseases in children.

Caseins↗
PubMed1997

Use of nested polymerase chain reaction to identify feline herpesvirus in ocular tissue from clinically normal cats and cats with corneal sequestra or conjunctivitis.

OBJECTIVE: To use a nested polymerase chain reaction (PCR) to detect feline herpesvirus (FHV-1) DNA in conjunctiva or cornea from clinically normal cats and cats with conjunctivitis or corneal sequestra. SAMPLES: Conjunctival snip biopsy specimens from 50 cats with conjunctivitis and 50 clinically normal cats; 28 keratectomy specimens from 26 cats with sequestra, and 13 specimens from clinically normal cats. PROCEDURE: Tissue specimens were digested, and FHV-1 DNA was amplified, using a double round of PCR. Products were visualized by use of agarose gel electrophoresis. RESULTS: Polymerase chain reaction was positive in 27 of 50 (54%) conjunctival specimens from cats with conjunctivitis and 6 of 50 (12%) specimens from clinically normal cats. Difference in the results between cats with conjunctivitis and clinically normal cats was statistically significant. Polymerase chain reaction was positive in 5 of 28 (18%) corneal specimens from cats with sequestra and 6 of 13 (46%) clinically normal cats. Distribution of positive results between clinically normal cats and those with sequestra was not significant. CONCLUSION: Cats with conjunctivitis were more likely to have a positive PCR result than were clinically normal cats, making it likely that FHV-1 was associated with the disease state. Herpesvirus DNA could not be detected in most corneas from cats with sequestra. CLINICAL RELEVANCE: Polymerase chain reaction is a useful clinical test for identifying FHV-1 DNA in cats with conjunctivitis, yielding greater sensitivity over that of current available tests. Herpesvirus may be less of a cause of corneal sequestration in the commonly affected breeds, Himalayan and Persian, than other factors, such as lagophthalmos or corneal metabolic defects.

Acute Disease↗
PubMed1997

Comparison of nested polymerase chain reaction, virus isolation, and fluorescent antibody testing for identifying feline herpesvirus in cats with conjunctivitis.

OBJECTIVE: To compare nested polymerase chain reaction (PCR), virus isolation (VI), and fluorescent antibody (FA) testing to detect feline herpesvirus (FHV) in cats with naturally acquired conjunctivitis or respiratory tract disease, or both. SAMPLES: Swab and microbrush specimens from the conjunctiva and throat were taken from 46 cats, allotted to 3 groups (conjunctivitis only, respiratory tract disease and conjunctivitis, and clinically normal). PROCEDURE: Cells from microbrush specimens were digested and herpesvirus DNA was amplified, using a double round of PCR. Products were detected by use of agarose gel electrophoresis. The VI and FA tests were performed in routine manner. RESULTS: Of 16 cats with conjunctivitis only, conjunctival specimens from 8 and throat specimens from 8 were FHV positive by PCR. None had positive results of VI or FA testing. Of 15 cats with respiratory tract disease and conjunctivitis, conjunctival specimens from 13 and throat specimens from 12 were FHV positive by PCR. A conjunctival specimen from 1 cat and throat specimens from 3 cats were FHV positive by VI. A conjunctival specimen from 1 cat was FHV positive by FA testing. Of 15 clinically normal cats, conjunctival and throat specimens from 2 cats were FHV positive by PCR; neither conjunctival nor throat specimens from these cats were FHV positive by VI or FA testing. CONCLUSION: For cats with respiratory tract disease and conjunctivitis, or with conjunctivitis only, nested PCR was more sensitive at detecting FHV than was VI or FA testing. CLINICAL RELEVANCE: Nested PCR is a more sensitive test than the currently available VI and FA tests for identifying FHV in cats with conjunctivitis.

Animals↗
PubMed1996

Methylphenidate slows right hemisphere processing in children with attention-deficit/hyperactivity disorder.

To examine the effects and particularly, any potential detrimental effects of methylphenidate on right hemisphere processing in children with attention-deficit/hyperactivity disorder (ADHD), the performance of 26 children (aged 8-15 years) with ADHD was compared under methylphenidate and placebo on various cognitive tasks in a double-blind within-subjects design. Results indicated that reaction times on a tachistoscopic task were slower on methylphenidate for stimuli that produced a left visual field advantage (reflecting better right hemisphere functioning) but not for stimuli that produced a right visual field advantage (reflecting better left hemisphere functioning) or for bilateral stimuli. It is argued that methylphenidate induces a slower response on tasks involving right hemisphere processing, resulting in slower reaction times and unchanged accuracy rates. Findings on two tasks that more closely reflect classroom-type tasks revealed an improvement in performance on methylphenidate, suggesting that any stimulant-induced benefits on learning style may have overcome detrimental effects on unilateral processing. These findings may help understand the complex, diverse, and sometimes unpredictable effects of psychostimulants on cognitive functioning that are observed clinically in individuals treated for ADHD.

Adolescent↗
PubMed1996

One Touch II hospital system for neonates: correlation with serum glucose values.

A correlation study was conducted to examine the relationship between results from LifeScan's One Touch II blood glucose monitoring system and laboratory analysis of serum glucose values in neonates. A total of 327 blood samples was obtained from newborn infants in a Level III NICU. The comparison of the paired results showed that the r value was .902. The overall results suggest that the LifeScan One Touch II set in the neonatal mode gives results showing good agreement with standard serum glucose values in neonates with serum glucose values < 100 mg/dl (5.6 mmol/liter).

Blood Glucose↗
PubMed1996

Developmental monitoring in primary care.

Monitoring child development is an essential part of primary health care. Successful surveillance depends on physicians' thorough knowledge of normal progress along the four developmental streams: motor, language, cognitive, and social and emotional. Being alert to "red flags" that suggest problems is important. Effective interventions can minimize developmental problems.

Child↗
PubMed1995

Anesthesia for scoliosis: dwarfism and congenitally absent odontoid process.

Scoliosis surgery presents the anesthetist with specific clinical challenges. Since scoliosis is the most common problem for which patients of congenitally short stature present to the operating room, the preoperative evaluation of dwarfs is discussed here in the context of a patient with spondyloepiphyseal dysplasia congenita. In the case described, many of the deformities associated with dwarfism were present. The significance of these to the preoperative, intraoperative, and postoperative care is discussed. Consideration is given to cervical spine abnormalities, congenital absence of the odontoid process, pulmonary function abnormalities, and mucopolysaccharidosis (a syndrome which may compromise airway management). The intraoperative monitoring of somatosensory evoked potentials and their significance are also discussed.

Adolescent↗
PubMed1994

Immunophenotypic differences between putative hematopoietic stem cells and childhood B-cell precursor acute lymphoblastic leukemia cells.

Acute leukemia cells express myeloid, B-lymphoid and T-lymphoid lineage specific antigens. Many acute leukemias express the hematopoietic progenitor cell antigen CD34. Three proposed models of the normal human hematopoietic stem cell include CD34+ Thy-1low Lin-, CD34+ CD38-, and CD34+ HLA-DR-. The patterns of expression of CD34, Thy-1, CD38, HLA-DR, and multiple lineage-specific antigens on 49 consecutive pediatric B-cell precursor acute lymphoblastic leukemia (ALL) cases submitted for immunophenotyping (36 at first diagnosis, 13 at relapse) were analyzed. CD34+ expression was observed in 67% of the cases. CD34+ expression correlated with Thy-1low expression and expression of myeloid antigens (p < 0.001 and < 0.025, respectively). The CD34+ Thy-1low phenotype was observed in 65% of the cases; the CD34+ CD38- or CD34+ HLA-DR- phenotypes were observed in only three cases. Examples of heterogeneous expression of CD34 and Thy-1 were found in six cases, but CD38 expression was always bright and homogeneous in all positive cases. The data from this analysis indicates that the CD34+ CD38- or CD34+ HLA-DR- phenotypes would be more useful than the CD34+ Thy-1low phenotype for distinguishing normal hematopoietic stem cells from leukemic cells in childhood B-cell precursor ALL.

ADP-ribosyl Cyclase↗
PubMed1994

Teacher-identified oral language difficulties among boys with attention problems.

Teachers evaluated the language functioning of 95 boys, aged 6.5 to 13.8 years, identified as having attention problems (AP, n = 30), learning disability (LD, n = 33), or average achievement (AA, n = 32). The three groups did not differ significantly (p > .05) in their frequency of articulation problems. Significantly (p < .05) more AP boys were rated as having pragmatics problems than both of the other groups. AP boys were also viewed as having a higher frequency of receptive/expressive language problems than were AA boys, but not compared with LD boys. LD and AA boys did not differ in their ratings for pragmatics problems, but more LD than AA boys were perceived as having receptive/expressive problems. The average incidence of all types of language problems was highest for the AP boys at 42% with poor pragmatics representing their most frequently rated language difficulty. AP boys' pragmatics difficulties seemed to be characterized by greater difficulty in maintaining than initiating a conversation compared with the other two groups. This difficulty was positively associated with the teachers' ratings of the AP boys' impulsivity.

Adolescent↗