Search PubMed⌕ Search

Biomedical subjects

K Pittman

Publications and source records attributed to K Pittman.

At least 19 recordsLinked to original sources
PubMed2005

Treatment and survival from colorectal cancer: the experience of patients at South Australian teaching hospitals between 1980 and 2002.

AIMS: To evaluate trends in colorectal cancer survival and treatment at South Australian teaching hospitals and degree of adherence to treatment guidelines which recommend adjuvant chemotherapy for Dukes' C colon cancers and combined chemotherapy and radiotherapy for high-risk rectal cancers. MATERIALS AND METHODS: Trends in disease specific survival and primary treatment were analysed, and comparisons drawn between diagnostic epochs, using cancer registry data from South Australian teaching hospitals. Statistical methods included univariate and multivariable disease specific survival analyses. RESULTS: Five-year survival increased from 48% in 1980-1986 to 56% in 1995-2002. Largest gains were for stage C, where survivals were higher when chemotherapy was part of the primary treatment. By comparison, gains in 1-year survival were largest for stage D. Chemotherapy was provided for 4% of patients with colorectal cancers in 1980-1986, increasing to 32% in 1995-2002. Among stage C cases below 70 years at diagnosis, the proportion having chemotherapy increased to 83% in 1995-2002. The most common chemotherapy was fluorouracil (5FU) as a single agent in 1980-1986 and 5FU with leucovorin in 1995-2002. As expected, radiotherapy was used more frequently for rectal than colon cancers, and particularly for stage C. Among stage C rectal cases below 70 years, the proportion having radiotherapy increased from 10% in 1980-1986 to 57% in 1995-2002. Approximately 93% of colorectal cancers were treated surgically. Patients not treated surgically tended to be aged 80 years or more and to present with distant metastases. CONCLUSIONS: Trends in chemotherapy and radiotherapy accord with evidence-based recommendations. There have been reassuring gains in survivals after adjusting for stage, grade and other prognostic indicators. The data show survival gains and treatment patterns that individual hospitals can use as benchmarks when evaluating their own experience.

Aged↗
PubMed2004

Bisphosphonate infusions: patient preference, safety and clinic use.

GOALS OF WORK: We set out to assess the preference of patients with common cancers involving bone receiving intravenous bisphosphonate therapy for either pamidronate (P) or zoledronic acid (Z) and their preference for the location of the infusion (clinic or home). We also aimed to monitor these patients' renal safety, and to compare their time in clinic to receive P and Z infusions. PATIENTS AND METHODS: Enrolled in the study were 184 patients, and all received initial infusions of Z (so any first infusion reactions did not confound preferences for P). For their second and third infusions, patients were randomized to receive Z then P or P then Z, and questioned on their preferences. For up to 1 year they continued on Z infusions every 3-4 weeks, while their renal safety was monitored. Where practical, later infusions were given at home (rather than in the clinic) and patients questioned on their preferred infusion location. In a convenience subset of 43 patients, clinic use for Z and P infusions was also measured by timing infusions and other procedures. MAIN RESULTS: Of 144 patients who received a third infusion, 138 responded to questions on bisphosphonate preference, and of these 138, 92% (127) preferred Z to P, because shorter infusions caused less disruption to their day. Only 12% of eligible patients (16/138) received home infusions, but 13/14 questioned preferred this location. Among 184 patients, 19 episodes of renal impairment were noted, mostly owing to disease progression (e.g. obstructive uropathy), with none linked to Z therapy. The mean clinic time taken to receive Z and any concomitant therapy was about half that for P (78 vs 161 min). CONCLUSIONS: Cancer patients prefer shorter bisphosphonate infusions-and at home, where practical. Regular Z 4 mg infusions appear to be safe in these patients, with routine monitoring of serum creatinine. Using Z rather than P could save busy cancer centres time and improve patient satisfaction.

Adult↗
PubMed2000

Listening to the quiet voices of Hispanic migrant children about health.

There is a paucity of literature related to school-aged migrant children's perceptions of their own health. To best provide culturally competent care, more information is needed about migrant children's experiences. Focus-group methodology allowed the voices of migrant children to be heard by primary health care providers at a summer school program for children of migrant farm workers in south Georgia. Seventy-three children participated in 14 focus-group sessions. Six themes emerged from the data that were analyzed by using a qualitative software system. They are healthy behaviors, acculturation issues, environmental influences, health care actions, health behavior outcomes, and learning needs. Emerging patterns within each theme render insight about these migrant children. The findings suggest implications for pediatric nurses related to culturally competent care.

Acculturation↗
PubMed1996

Reverse transcriptase-polymerase chain reaction for expression of tyrosinase to identify malignant melanoma cells in peripheral blood.

BACKGROUND: Circulating tumour cells in the peripheral blood may be important for haematogenous spread of disease. The detection of these cells may therefore be a poor prognostic indicator. Reverse-transcriptase polymerase chain reaction (RT-PCR) of target tumour-specific protein expression has been used as a sensitive and specific method for the detection of these tumour cells. Initial reports by our laboratory and other suggested RT-PCR amplification of the enzyme tyrosinase is a useful method for detection of melanoma cells in peripheral blood [1-3]. PATIENTS AND METHODS: In this report, we have evaluated the application of RT-PCR for tyrosinase mRNA as a detection method for melanoma cells in a series of 24 patients with advanced, metastatic malignant melanoma. A single round RT-PCR method is described. RESULTS: The single round RT-PCR was as sensitive as previously described nested PCR methods, and had the advantage of reduced contamination risks. Blood samples from three out of the twenty-four patients were positive. CONCLUSIONS: The frequency of tumour cell detection in peripheral blood from patients with advanced disease was lower than previously reported. It may be only small numbers of circulating tumour cells are present at any one time in the peripheral blood of patients with malignant melanoma. If this is the case increased sampling will improve detection frequency. Alternatively, dissemination of melanoma through peripheral blood may be a rare event. In our experience, RT-PCR for tyrosinase mRNA as a staging test for melanoma patients must be interpreted cautiously.

Adult↗
PubMed1995

Detection of epithelial cancer cells in peripheral blood by reverse transcriptase-polymerase chain reaction.

Circulating cancer cells in the blood play a central role in the metastatic process. Their number can be very small and techniques for their detection need to be both sensitive and specific. Polymerase chain reaction (PCR) has been successfully used to detect small numbers of tumour cells in haematological cancer in which abnormalities in DNA are sufficiently consistent to make this possible. For most solid tumours this not yet feasible. However, we have found that reverse transcriptase (RT)-PRC for tissue-specific gene expression is a useful technique for identifying small numbers of circulating cells in melanoma and neuroblastoma patients. In this report we describe detection of colon carcinoma cells by RT-PCR using CK 20 mRNA as a marker. Unlike other cytokeratin genes examined (CK 8 and CK 19), CK 20 was not transcribed in normal haematopoietic cells. This suggests a role for RT-PCR in the detection of colon carcinoma metastasis in blood and bone marrow, using CK 20 as the target gene. Future analysis of clinical material will determine the clinical significance of this technique.

Adenocarcinoma↗
PubMed1995

Marked prolongation of incompatible class I deficient heart allografts: paradoxical effects between primarily and secondarily vascularized allografts.

These studies argue strongly against the widespread use of skin grafts for rejection testing. Primarily vascularized grafts of a clinically grafted organ would seem to be much more relevant to future studies. These results suggest that the elimination of either class I or class II antigens in grafts or techniques to modulate these antigens or reduce the degree of incompatibility of these antigens by tissue typing should be actively pursued for solid organ grafting in the future.

Animals↗
PubMed1995

Deoxyspergualin is a unique immunosuppressive agent with selective utility in inducing tolerance to pancreas islet xenografts.

Recent studies of DSG have demonstrated that this agent has a unique ability among immunosuppressive drugs to induce long-term survival and functional tolerance of discordant islet xenografts from pig to the Lewis rat. In addition, DSG was found to be nontoxic to islet cells in culture and without any inhibitory effect upon insulin secretion in contrast to azathioprine, FK 506, and CyA. The long-term functional tolerance seen with these islets appears to involve a stable block of antidonor humoral immunity, although more testing is necessary to characterize the precise state producing functional tolerance in this model. Other studies presented at this meeting demonstrate the ability of DSG and RATG immunosuppression to produce long-term discordant islet survival in the NOD mouse, which suffers from a virulent autoimmune condition that destroys transplanted islets in most NOD models shortly after transplantation, even when the islets are microencapsulated. The functional tolerance is especially difficult to achieve with a discordant xenograft and thus the ability of RATG and DSG to achieve this impressive. Long-term studies using DSG and total lymphoid irradiation suggest that RATG is not essential to long-term survival but clearly it is quite synergistic with DSG and also has the advantage of being nontoxic. In fact, all animals receiving the DSG/RATG therapy were essentially free of toxicity and no deaths were observed that could be attributed to the drug therapy. This short-term course of administration of the drugs helped achieve this lack of toxicity. The high levels of synergism of ATG in this model could be related to the numerous monoclonal reactivities seen in polyclonal ATG with demonstrated titers of 1 to 4000 or greater for a number of specificities associated with B cells and macrophages, which could well be contributing to the block of humoral antibody previously demonstrated in DSG/RATG treated animals. The DSG, however, is especially effective in synergizing an antihumoral antibody response and can be shown to result in a striking decrease in early humoral antibody production following transplantation. Overall, these studies demonstrate a high potential of this immunosuppressive therapy to promote long-term discordant islet xenograft survival and functional tolerance without chronic rejection or the islet toxicity common to the currently used immunosuppressive agent. DSG may have a wide potential utility in islet transplantation but it appears to have its strongest effect in islet xenografting.

Animals↗
PubMed1994

Considerations of the validity of mouse-to-rat xenograft combinations in xenograft testing.

These results indicate that both the choice of species combination as well as the choice of the donor organ studied can be crucial in the reproducibility, validity, and probably the relevance of xenograft testing. The vexatious results often encountered in a variety of mouse strains should lead to caution in the use of mouse models in general. Perhaps it is fair to say that the authors of mouse studies should indicate some particular reason for choice of the combination of rat-to-mouse transplant rather than mouse-to-rat as their primary model, or utilize the reciprocal species combination as a control. In regard to choice of organ xenograft transplant, the primarily vascularized heart xenograft is an excellent model. In contrast to skin, isolated pancreas islet, and some other xenograft organ models, the primarily vascularized heart model is a valid one and shows little variance in mean survival with a given treatment in the mouse. If a choice of rat-to-mouse or other species xenograft to mouse recipients is necessary or desirable, the primarily vascularized heart should be used as the organ of choice. In the emerging field of xenograft testing, the reproducibility, validity, and relevance of these xenograft models will be crucially important in deriving information useful for expansion of xenografting and to higher animals ultimately into clinical practice. There is little doubt that the rodent studies in both xenografts and allografts have provided a wealth of the immunological and surgical information that was obtained in a cost-effective manner with minimal ethical problems.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗