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K J Carney

Publications and source records attributed to K J Carney.

4 recordsLinked to original sources

Sex determination in the monoecious species cucumber is confined to specific floral whorls.

In unisexual flowers, sex is determined by the selective repression of growth or the abortion of either male or female reproductive organs. The mechanism by which this process is controlled in plants is still poorly understood. Because it is known that the identity of reproductive organs in plants is controlled by homeotic genes belonging to the MADS box gene family, we analyzed floral homeotic mutants from cucumber, a species that bears both male and female flowers on the same individual. To study the characteristics of sex determination in more detail, we produced mutants similar to class A and C homeotic mutants from well-characterized hermaphrodite species such as Arabidopsis by ectopically expressing and suppressing the cucumber gene CUCUMBER MADS1 (CUM1). The cucumber mutant green petals (gp) corresponds to the previously characterized B mutants from several species and appeared to be caused by a deletion of 15 amino acid residues in the coding region of the class B MADS box gene CUM26. These homeotic mutants reveal two important concepts that govern sex determination in cucumber. First, the arrest of either male or female organ development is dependent on their positions in the flower and is not associated with their sexual identity. Second, the data presented here strongly suggest that the class C homeotic function is required for the position-dependent arrest of reproductive organs.

Amino Acid Sequence↗

Separated pyelocolocutaneous diversion after bilateral ureterectomy and radical cystectomy for transitional cell carcinoma.

OBJECTIVES: To report a technique for excision of bilateral ureteral transitional cell carcinoma which preserves renal function and provides ready access for endoscopic follow-up and therapy of the renal pelvis. METHODS: The operative procedure of bilateral ureterectomy with construction of a separated pyelocolocutaneous diversion utilizing transverse colon is described and the clinical course of 4 patients is reported. RESULTS: All 4 patients maintained excellent renal function and normal electrolytes. Conduit urine cytologic studies and renal pelvis endoscopic examinations have remained normal. Parastomal herniation was the most frequently observed postoperative complication. CONCLUSIONS: This approach is well suited for the treatment of bilateral ureteral transitional cell carcinoma. Long-term complications are minimal and renal function is preserved. Periodic endoscopic visualization of each renal pelvis with resection and fulguration and/or instillation of immunotherapeutic or chemotherapeutic agents for recurrent renal pelvic lesions is readily accomplished.

Aged↗

Left upper lobe mass and diffuse reticular-nodular infiltrate.

We encountered a clinical problem in a young man who presented with a left upper lobe mass and a diffuse reticular-nodular infiltrate. We thought we had appropriately applied Murphy's Law (the famed bank robber who "went where the money is"), and Ockham's Razor (the philosopher William of Ockham [1285 to 1349]-"Entities are not to be multiplied beyond necessity") as we rapidly diagnosed the lung mass with computed tomography, scintigraphy, and fine-needle aspiration. However, when his invaluable previous chest radiographs arrived, bronchoscopy with transbronchial biopsy, bronchoalveolar lavage, brushings, and postbronchoscopy sputum revealed the more ominous diagnosis in this patient. This case illustrates the complementary nature of current imaging and bronchoscopy techniques; but, even more importantly, it demonstrates the value of the history coupled with the previous radiograph. Even an unusual case can provide lessons in cost containment.

Adenocarcinoma↗

Prognostic significance of tumor markers in colorectal cancer patients: DNA index, S-phase fraction, p53 expression, and Ki-67 index.

Risk of colorectal cancer recurrence has traditionally been determined by use of pathologic staging. However, it is apparent that subgroups of patients exist within tumor stages whose clinical behavior differs. This study was undertaken to identify tumor-associated factors that might be predictive of outcome in patients with intermediate stages who will benefit the most from postsurgical adjuvant therapy. Seventy patients with stage II and III colorectal cancer were assessed for DNA index, S-phase fraction, p53 expression, and Ki-67 index. Tumor recurrence was analyzed by means of nonparametric tests and Cox proportional hazard models incorporating standard clinical and pathologic criteria. Of the four prognostic markers evaluated, Ki-67 index was significantly associated with disease recurrence (P = 0.02), whereas DNA index, S-phase fraction, and p53 expression were not. After stratification by tumor stage, significant associations between Ki-67 index and disease recurrence were retained in stage II tumors (P = 0.01) but not in stage III tumors (P = 0.23). Cox proportional hazard regression analysis indicated that among stage II patients, those with a Ki-67 index >45% were associated with 6.5 times greater risk for disease recurrence than those with a Ki-67 index >/=45%. It was concluded that an elevated Ki- 67 index is associated with an increased risk of tumor recurrence in stage II colorectal cancer.

Aged↗