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R J O'Hara

Publications and source records attributed to R J O'Hara.

6 recordsLinked to original sources
PubMed1998

Impaired interleukin-12 production is associated with a defective anti-tumor response in colorectal cancer.

INTRODUCTION: Despite development of many chemotherapeutic regimens, colorectal cancer continues to have a high mortality. One of the major new potential therapies is interleukin-12, a heterodimeric cytokine produced by antigen presenting cells. In vitro and in vivo studies have demonstrated the role of interleukin-12 in stimulating a cell-mediated anti-tumor response against a number of colon adenocarcinoma tumor models. However, it is unknown whether patients with colorectal cancer have impaired interleukin-12 production. A study was performed to investigate production of interleukin-12 preoperatively and the relationship between these levels and disease stage at surgery. METHODS: Preoperative peripheral blood mononuclear cells from colorectal cancer patients and age-matched controls were stimulated by Staphylococcus aureus Cowan's Strain 1 (0.0075 percent wt/vol) in vitro for 24 hours. Expression of interleukin-12 was then assessed by enzyme-linked immunosorbent assay. A single pathologist assessed the tumors for stage according to TNM and Dukes classifications. RESULTS: Twenty-eight patients with colorectal cancer and 14 controls were recruited for the study. Interleukin-12 production was significantly impaired in patients with colorectal cancer compared with controls (P = 0.014), especially those with advanced disease: Dukes C, P = 0.001 and T4, P < 0.05. CONCLUSION: Interleukin-12 production is impaired in patients with colorectal cancer, especially those with advanced disease, suggesting a defective Thl-mediated anti-tumor response. These patients may well benefit from exogenous interleukin-12 treatment.

Adenocarcinoma↗
PubMed1998

Advanced colorectal cancer is associated with impaired interleukin 12 and enhanced interleukin 10 production.

Interleukin 12 (IL-12) is a heterodimeric cytokine that has been demonstrated to have a major role in stimulating a cell-mediated antitumor response. IL-10, a product of T helper 2 lymphocytes, is its most potent inhibitor. The aim of this study was to investigate whether patients with colorectal cancer had an imbalance in production of IL-12 and IL-10 preoperatively, and whether this was associated with advanced disease at surgery. Blood was obtained before surgery from 60 patients with colorectal cancer and from 30 controls. Peripheral blood mononuclear cells were incubated with Staphylococcus aureus Cowan's strain 1 in vitro for 24 h to assess IL-12 expression after stimulation, and serum was used for IL-10 measurement. IL-12 and IL-10 levels were assessed by ELISA. A single pathologist staged the tumors according to the tumor-node-metastasis (TNM) and Dukes' classifications. Patients with colorectal cancer had significantly lower levels of IL-12 (P <0.001) and higher levels of IL-10(P = 0.004) compared to controls. In addition, lower levels of IL-12 were detected in those patients who were node positive (P<0.05), had Dukes' C lesions (P < or = 0.001), and T3 or T4 lesions (P<0.033) when compared to controls. Patients with Dukes' B and C lesions (P<0.01) and T3 and T4 lesions (P<0.05) also had higher levels of IL-10 compared to controls. This study is the first to demonstrate that patients with colorectal cancer have decreased IL-12 production and increased serum IL-10. This suggests an impaired T helper 1 cell-mediated antitumor response and provides some justification for exogenous IL-12 therapy or anti-IL-10 therapy in these patients.

Adult↗
PubMed1996

Conservative management of infective mastitis and breast abscesses after ultrasonographic assessment.

Current practice in this unit for a suspected breast abscess is preliminary ultrasonographic scan, aspiration of any pus, antibiotic therapy and repeat aspiration in the outpatient clinic if necessary. Inflammatory masses are treated with antibiotics alone. A retrospective review of this strategy has been made. Over a 2-year interval 53 patients were admitted to hospital with a suspected breast abscess. Twenty-two abscesses were aspirated, of which 19 resolved and three required subsequent incision and drainage. Eight patients underwent primary incision and drainage, one of whom required a second drainage procedure. In five patients the abscess discharged spontaneously before intervention. The remaining 18 patients were found on ultrasonography to have inflammation without evidence of focal pus which settled with antibiotic therapy in all but two patients. One of these was found to have an inflammatory cancer and the other developed an abscess, which was drained. Aspiration combined with ultrasonographic imaging is an effective alternative to incision and drainage.

Abscess↗
PubMed1986

Bladder dysfunction and neurosyphilis.

Neurosyphilis today is a rare problem. We describe a man who presented with organic brain syndrome, psychosis and incontinence, and diagnosis was neurosyphilis with resultant bladder dysfunction. Urodynamic studies defined the voiding dysfunction as detrusor areflexia with a positive bethanechol test. This case reminds us of the necessity of obtaining a test for venereal disease to rule out neurosyphilis in patients with idiopathic voiding dysfunction.

Adult↗
PubMed1983

Motor aphasia unaccompanied by faciobrachial weakness.

Most patients with motor aphasia resulting from lesions of the left frontal opercular region have weakness of the right face and arm. We report a 43-year-old man who suffered mutism and agraphia unaccompanied by right-sided weakness after embolic infarction of Broca's area.

Adult↗