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T Parker

Publications and source records attributed to T Parker.

At least 55 records · Page 3Linked to original sources
PubMed1996

Characterization of a collagenous cementum-derived attachment protein.

We report further characterization of a cementum-derived protein that promotes the adhesion and spreading of periodontal cells. The cementum attachment protein (CAP) was extracted from bovine cementum, separated by diethylamino ethyl (DEAE)-cellulose chromatography, and purified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and C18 reverse phase high performance liquid chromatography. The purified preparation contained a single protein band migrating with M(r) 56,000. It did not cross-react with polyclonal antibodies to osteopontin, vitronectin, or other attachment proteins. The attachment activity was resistant to chondroitinase ABC digestion. An internal amino acid sequence of six peptides was determined by microsequencing, and the peptide sequences were not present in other attachment proteins described in cementum. Four sequences contained Gly-X-Y repeats typical of collagen helix. One 17 amino acid peptide had 82% homology with a type XII collagen domain. However, bovine type XII collagen did not promote fibroblast attachment. Although another 19-amino-acid-long peptide had 95% homology to bovine alpha 1 [I], two other peptides were only 74% and 68% homologous, and the CAP was not recognized by anti-type I collagen antibody. The attachment activity of CAP was susceptible to bacterial collagenase. The CAP did not cross-react with antibodies to type V, XII, and XIV collagens. These data and our previous immunostaining data indicate that the CAP is not related to other collagens or attachment proteins and that it is a collagenous attachment protein localized in cementum.

Animals↗
PubMed1996

Malignant melanoma.

BACKGROUND: Melanoma is being diagnosed, treated, and followed more and more by dermatologists. It is important that we understand its biology, the background behind recommended treatment protocols, and how to follow patients long-term. OBJECTIVE: To highlight topics related to melanoma that are often taken for granted or misunderstood so that we can offer these patients a more rational approach. RESULTS: We explored the concepts of melanoma growth and spread and the basis for its current treatment modalities and prognosis. CONCLUSION: Malignant melanoma is still a difficult disease to control. There is however a great fund of knowledge regarding its behavior that we already possess. By analyzing old and new concepts regarding its pathology and integrating them together we can simplify and enhance our approach to its treatment.

Combined Modality Therapy↗
PubMed1996

Home enteral tube feeding in East Anglia.

OBJECTIVE: To establish the profile of patients receiving home enteral tube feeding (HETF) in East Anglia, to assess the adequacy of care, and to consider the causes and implications of differences in the geographic prevalence of HETF. DESIGN: A 1-year prospective study. SETTING: Eight independently funded districts within East Anglia. SUBJECTS: Basic clinical data were available from 234 patients, 191 of which were tube-fed in the same district as that which initiated treatment, with detailed data obtained from 126. OUTCOME MEASURES: Prevalence, complications in relation to the dietetic support available, and standards of care in relation to those set in the reports of the King's Fund and the British Association of Parenteral and Enteral Nutrition. RESULTS: The patients, who were usually elderly subjects or children, had severe disabilities: 40% were unable to walk: 39% were unable to speak; and 20% were housebound. In all cases enteral tube feeding had been initiated in hospital but in this survey we found inadequate training for home care in 23%, inadequate support and follow-up in 20%, inadequate equipment in 41%, uncertainties regarding organisation, and various clinical problems such as feed regurgitation, in 22%, aspiration pneumonia in 13% , which occasionally led to hospitalization (4%), and frequent but usually minor peristomal problems in patients with gastrostomies. There was a direct correlation between the prevalence of HETF (which varied fourfold between districts) and the number of NHS dieticians per head of population; and in inverse correlation with respect to requests by patients for more support (r = 0.97), complaints of blocked tubes (r = 0.82) and the need for hospital help. CONCLUSION: HETF provides an important form of support to a small group of severely disabled patients. There are important differences between districts in the prevalence of HETF which may be related to variation in local expertise and available support staff. The standards of care did not always conform to those set in the King's Fund report and BAPEN report on Enteral and Parenteral Nutrition in the community.

Adolescent↗
PubMed1995

The law hath not been dead: protecting adults with mental retardation from sexual abuse and violation of their sexual freedom.

The extent to which three professional groups (law enforcement officers, licensing personnel, and sex educators/counselors) utilize legally relevant criteria when assessing the sexual abuse of an adult with mental retardation was examined. Subjects were randomly assigned to one of four experimental conditions that varied in terms of the ability of a woman with mental retardation to understand concepts involving the nature and consequences and right of volition in a sexual relationship. The results indicated significant effects for both treatment condition and group. Thus, more explicit, standardized criteria should be developed for professionals to utilize when assessing consent involving possible sexual abuse of adults with mental retardation.

Adult↗
PubMed1995

Diagnostic laparoscopy: a 5-year experience in a hepatology training program.

Diagnostic laparoscopy continues to have a role in the evaluation and diagnosis of acute and chronic liver diseases, primary and metastatic liver tumors, and peritoneal diseases. We retrospectively reviewed the records of 1794 diagnostic laparoscopies performed at our institution from 1987 to 1992 to identify the indications, results, and safety of this procedure in our training program. A definitive diagnosis was made in 91% of cases with biopsy performed in 93%. Chronic liver disease was evaluated in 890 patients, and a diagnosis was made in 98%. Four hundred thirty-seven patients were evaluated for suspected primary or metastatic carcinoma, and a diagnosis was made in 85%. Ascites was evaluated in 73 patients, and a diagnosis was made in 82%. One-hundred sixty-four patients were evaluated for abnormal liver function tests, and a diagnosis was made in 91%. HIV-related liver function test abnormalities were evaluated in 67 patients, and a diagnosis was made in 81%. One hundred sixty-three patients underwent diagnostic laparoscopy for the evaluation of hepatomegaly, splenomegaly, unexplained portal hypertension, fever of unknown origin, and cholestasis, and a diagnosis was made in 74% of cases. Eight major complications (including abdominal viscus perforation, hemobilia, splenic laceration, bleeding) and thirty-one minor complications were seen. Our findings confirm that diagnostic laparoscopy is a safe and valuable procedure in the evaluation of chronic liver disease.

Chronic Disease↗
PubMed1995

Procollagen-III peptide and chronic viral C hepatitis.

UNLABELLED: Chronic hepatitis develops in at least half of persons acutely infected with hepatitis C virus (HCV). Ten to 25% of these patients will develop cirrhosis. Serum procollagen-III peptide (PIIIP) may be of value in predicting the development of chronic active fibrogenic liver disease. It has been reported that in chronic viral C hepatitis, the levels of hepatitis C virus-RNA (HCV-RNA) correlate directly with the severity of hepatic histology and inversely with response to interferon therapy. OBJECTIVES: The aims of this study were to correlate the level of PIIIP with HCV-RNA concentrations, ALT values, and histological severity in patients with chronic viral C hepatitis. METHODS: Eighty-six patients with chronic C hepatitis were divided into three groups: group I (n = 34), mild chronic active hepatitis, group II (n = 25), moderate to severe chronic active hepatitis, and group III (n = 27), cirrhosis. HCV-RNA was measured by Quantiplex, and PIIIP was measured by radioimmunoassay-gnostic assay. RESULTS: Mean +/- SD level of ALT in group I was 114 +/- 48 U/L, group II was 169 +/- 115 U/L, and group III was 160 +/- 94 U/L. The mean +/- SD level of HCV-RNA in group I was 110 +/- 130 x 10(5) Eq/ml, in group II was 140 +/- 140 x 10(5) Eq/ml, and in group III was 70 +/- 80 x 105 Eq/ml. The mean +/- SD level of PIIIP in group I was 0.6 +/- 0.2 U/ml, in group II was 0.9 +/- 0.4 U/ml, and in group III was 1.2 +/- 0.6. There was a significant difference in the levels of PIIIP among the three groups (p = 0.0001). There was no correlation among ALT, HCV-RNA, and PIIIP in any of the three groups. CONCLUSIONS: PIIIP peptide determinations in patients with chronic viral C hepatitis are reflective of histological severity and may provide relatively noninvasive means of following disease progression.

Alanine Transaminase↗
PubMed1994

A phase II trial of recombinant leukocyte interferon plus doxorubicin in patients with hepatocellular carcinoma.

A Phase II trial of combination therapy with recombinant leukocyte interferon (alpha IFN) and doxorubicin was performed in patients with unresectable hepatocellular carcinoma. alpha IFN was administered at a starting dose of 20 x 10(6) U/m2 intramuscularly or subcutaneously with doxorubicin 20 mg/m2 intravenously weekly x 3 weeks followed by a 2-week period rest. There were 22 patients entered into the study. Among the 21 patients, there were 2 partial responses (10%), one minor response, and one patient had stable disease. Toxicity was generally tolerable, with fever, fatigue, and myelosuppression being the most common side effects. This combination of weekly recombinant leukocytic interferon and doxorubicin has modest and limited activity in hepatocellular carcinoma.

Adult↗
PubMed1993

Detection of hepatitis C virus antibody by first and second generation assays and polymerase chain reaction in patients with autoimmune chronic active hepatitis types I, II, and III.

In this study we have attempted to classify a group of North American patients with autoimmune chronic hepatitis into types I, II, and III according to the class of autoantibody present in serum, and determine the prevalence and significance of antibody to hepatitis C virus (anti-HCV). A total of 62 patients (type I, 51; type II, 3; type III, 8) were tested with first-generation enzyme-linked immunosorbent assay (ELISA)-1. Seropositive patients were assessed by second-generation recombinant immunoblot assay (RIBA)-2 and polymerase chain reaction (PCR). Our results demonstrate that 12 (19%) of the 62 patients with autoimmune hepatitis were anti-HCV ELISA-1 positive (type I, 9; type II, 1; type III, 2). Only one patient with type II autoimmune hepatitis was reactive by RIBA-2 and PCR. Eight of the 12 seropositive patients entered remission after corticosteroid therapy and seven of them became seronegative by ELISA-1. The RIBA-2 and PCR reactive patient did not respond to immunosuppressive therapy and remained seropositive. We conclude that there is a low prevalence of anti-HCV antibody in autoimmune hepatitis. Results based only on ELISA-1 anti-HCV testing can be misleading, and second-generation testing is necessary to recognize the presence of HCV infection. The fact that the only RIBA-2 reactive patient had type II autoimmune hepatitis may suggest a role for HCV infection in the pathogenesis of this condition. Nevertheless, corticosteroid therapy remains effective in those patients who are ELISA-1 seropositive, but RIBA-2 and PCR nonreactive.

Adolescent↗
PubMed1992

Prevalence of antibodies to hepatitis C virus among patients with cryptogenic chronic hepatitis and cirrhosis.

Many cases of chronic hepatitis and cirrhosis cannot be attributed to a known cause and are collectively referred to as cryptogenic chronic liver disease. We have evaluated the role of the hepatitis C virus in the pathogenesis of this condition in a retrospective serum analysis for antibody to hepatitis C virus in 129 patients with cryptogenic liver disease. Other causes of chronic hepatitis and cirrhosis were ruled out by clinical, serum biochemical and serological techniques. All 129 patients were HBcAg negative, but 28 (22%) had antibody to HBcAg. Sera were tested by radioimmunoassays using recombinant peptides for antibodies to nonstructural (C100-3 and C33c) and structural regions (C22) of HCV. Among the 129 patients, 61 (47%) had antibody to C100-3, 76 (59%) had antibody to C33c and 74 (57%) had antibody to C22. Seventy-nine (61%) were reactive with at least one and 76 (59%) were reactive with at least two HCV peptides (this is the criterion used for hepatitis C virus antibody reactivity). A proportion of patients with chronic hepatitis and cirrhosis (55 of 91; 60%) similar to that of patients without cirrhosis (21 of 38; 55%) had hepatitis C virus antibody. No significant clinical, serum biochemical or histological differences were noted between the group of patients with hepatitis C virus antibody and those without this antibody reactivity. Thus more than half the patients with cryptogenic chronic liver disease had hepatitis C virus antibody, suggesting that chronic HCV infection plays a major role in the origin of cryptogenic chronic hepatitis and cirrhosis.

Adult↗
PubMed1992

Transfer of staff training from workshops to group homes: a failure to generalize across settings.

Two experiments were conducted to assess acquisition and generalization of skills acquired in a workshop by trainees who were primary caregivers on the staffs of group homes for developmentally disabled clients. In Study 1, 31 staff trainees received an intensive, 1-week workshop in behavioral theory and treatment techniques. When assessed at the workshop site, these staff trainees showed increased treatment skills, relative to 18 staff trainees who did not participate in the workshop. In Study 2, pre- and postworkshop observations were taken on 53 developmentally disabled clients in group homes where the staff trainees worked. These observations provided no evidence that the workshop had any effect on group home client functioning. Future training programs for caregivers may be more successful if they occur in the group home, involve clients in the home, and enlist the support of supervisory staff, rather than focusing only on primary caregivers.

Activities of Daily Living↗
PubMed1992

Patient controlled analgesia--a pharmacy based service.

Patient controlled analgesia (PCA) is a proven method of administering analgesics via programmable infusion devices to relieve postoperative pain and pain associated with terminal illnesses. In mid-1989, a pain management service was started in the authors' hospital by the anesthesiology service. Since pharmacists had been previously involved in PCA postoperative pain management, it was decided they would continue in that capacity with the pain management service. Responsibility for procuring, storing, and programming the pumps, as well as drug preparation and patient instruction remains an integral part of the daily operation of our pharmacy. Physician orders written by the anesthesiologists for PCA therapy are processed in the pharmacy computer. The drugs are prepared, and pumps are programmed and primed by the central intravenous (IV) admixture service. The pumps with the drugs and accessory administration set and supplies are sent to satellites where staff pharmacists aid the nurses in starting the pumps and training the patients in their correct use. All subsequent programming including dose changes, rate changes, boluses, bag changes, and problem resolution are the responsibility of the staff pharmacists. Pharmacists are periodically certified in programming skills as part of the department's quality assurance program. In 1990, over 1800 patients received the benefits of this innovative service.

Analgesia, Patient-Controlled↗
PubMed1991

Protocol for genetic testing in Huntington disease: three years of experience in Minnesota.

Molecular genetic testing for Huntington disease (HD) by linkage analysis of DNA markers close to the HD gene has been possible since the mid-1980s. Because of ethical and practical concerns about this kind of testing, most groups performing the test in the past have operated under lengthy research protocols designed to assess the psychological morbidity of the presymptomatic diagnosis of a fatal disease. Our approach to HD testing is service-oriented, and our testing process has been designed to be flexible, to meet the varying needs of our patients. Between 1988 and 1990, 87 inquiries about the test have been received; 22 inquiries had family structures which were unsuitable for linkage analysis. Eleven of the 37 individuals who entered the testing program have not completed it. Of 19 patients who have received DNA results, seven received an increased risk of carrying the HD gene, and ten, a decreased risk. For two additional individuals, nonpaternity resulted in a negligible risk for HD. Several of those consulted, or their spouses, have had continuing outpatient counseling since completing the test; none have required hospitalization. Our short-term results indicate that molecular genetic testing for HD can be performed safely in a clinical setting using our protocol. As molecular genetic testing for HD and other diseases moves out of research centers and into clinics, clinicians must devise practical strategies for providing the medical, genetic, and psychological services needed for the growing number of individuals who will seek such testing.

Genetic Linkage↗
PubMed1990

Hepatitis C-associated hepatocellular carcinoma.

In the United States, a large percentage of patients with hepatocellular carcinoma are serologically negative for hepatitis B. We conducted a retrospective study to determine the prevalence of hepatitis C antibody in the sera of 59 patients with hepatocellular carcinoma who were HBsAg-negative and had no evidence of alcoholic liver disease, primary biliary cirrhosis, autoimmune hepatitis, hemochromatosis or alpha 1-antitrypsin deficiency. Twenty patients (34%) were hepatitis C antibody-positive and hepatitis B core antibody-negative. All twenty patients had underlying cirrhosis, and seven (35%) had histories of transfusions. Eleven (19%) additional patients were also hepatitis C antibody-positive but were hepatitis B core antibody-positive as well. Twenty-one (36%) patients were both hepatitis C antibody- and hepatitis B core antibody-negative and seven (12%) were hepatitis C antibody-negative but hepatitis B core antibody-positive. The prevalence of hepatitis C antibody was also determined among three other population groups serving as controls and found to be 14% in 28 HbsAg-positive patients with hepatocellular carcinoma, 44% in 76 patients with cryptogenic cirrhosis and 0.5% in 200 consecutive volunteer blood donors. We conclude that hepatitis C antibody is prevalent among patients with hepatocellular carcinoma and may therefore be a common causative agent of this disease. A significant number of patients with and without cirrhosis, negative for hepatitis C antibody and hepatitis B core antibody, remain without a discernible cause for this malignancy. Perhaps a second- or third-generation test will detect hepatitis C antibody in some of these patients.

Carcinoma, Hepatocellular↗
PubMed1988

Small bowel edema: mosaic pattern.

We report an unusual radiographic appearance of small bowel submucosal edema produced by obstruction from metastatic colorectal carcinoma. The distinctive muscosal pattern of raised polygonal plaques is the same mosaic pattern described in the colon and referred to as "urticaria." This mosaic pattern in the small bowel has not previously been reported.

Aged↗