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Biomedical subjects

K R Billings

Publications and source records attributed to K R Billings.

12 recordsLinked to original sources
PubMed2000

Screening sinus CT scans in pediatric bone marrow transplant patients.

OBJECTIVE: To determine how sinus disease noted on pre-bone marrow transplant (BMT) screening sinus computed tomography (CT) scans relates to subsequent development of clinical and/or radiographic sinusitis and correlates with overall prognosis. METHODS: A retrospective review of medical records, CT scans, and BMT database statistics was performed on all pediatric BMT recipients from January 1992 through December 1997. Fifty-four pre-BMT CT scans were performed on 51 children, aged from 2 months to 17 years. Sinus disease was staged according to criteria established by Lund and Kennedy [V.J. Lund, D.W. Kennedy, Ann. Otol. Rhinol. Laryngol. S167 (1995) 17-21.]. RESULTS: The average age of BMT recipients was 6.8 years. Most common oncologic diagnoses included acute myelogenous leukemia (37%), acute lymphoblastic leukemia (17%), and stage IV neuroblastoma (13%). Screening sinus CT scans were routinely performed 1-3 months prior to BMT. On pre-BMT CT scans 48% of the patients had no evidence of sinus disease, 25.9% mild disease, 9.3% moderate disease, and 16.7% severe disease. Two-thirds (66.7%) of patients with severe sinus disease on pre-BMT CT scans experienced clinical sinusitis post-BMT. In contrast, sinus symptoms were much less common (21.4%) in those with mild disease on CT scan. Overall, 39.3% of patients with sinus abnormalities on pre-BMT CT scans had clinical sinusitis during their post-BMT course, compared to 23.1% of those with normal CT scans pre-BMT. In addition, those patients demonstrating sinus disease on their pre-BMT CT scan were more likely to have radiographic sinusitis post-BMT (25.0%) than those with no disease (7.7%). Seventy-eight percent of those with severe sinusitis had died by 2-year follow up, compared to 69.2% of patients with normal CT scans pre-BMT. CONCLUSIONS: Severity of radiographic sinus disease on pre-BMT CT scans was noted to correlate with clinical and radiographic sinusitis later in the post-BMT course, and was associated with a trend toward decreased survival. Pre-BMT CT scans may be useful in determining which children need early and more aggressive intervention for clinical sinusitis post-BMT.

Adolescent↗
PubMed2000

Respiratory difficulty following bismuth subgallate aspiration.

Bismuth subgallate, an agent that initiates clotting via activation of factor XII, has been advocated for use in controlling bleeding during tonsillectomy and adenoidectomy. Direct aspiration of bismuth has produced pulmonary complications in laboratory animals, but no clinical correlation in humans has been previously described. We report 2 cases of bismuth aspiration that resulted in respiratory difficulty after tonsillectomy and adenoidectomy. Neither child's respiratory compromise required airway intubation. This report of pulmonary complications secondary to bismuth aspiration should alert surgeons to the potential for airway problems when using bismuth as a hemostatic agent for tonsillectomy and adenoidectomy.

Adenoidectomy↗
PubMed1999

Causes of pediatric sensorineural hearing loss: yesterday and today.

OBJECTIVE: To ascertain the present common causes of sensorineural hearing loss (SNHL) in children and compare them with those of previous reports. DESIGN: A retrospective review of the medical records for all children with a diagnosis of SNHL seen from January 1, 1993, through September 30, 1996, at our institution. SETTING: A tertiary care children's hospital. PATIENTS: Three hundred one children, aged 1 week through 18 years, who presented for evaluation of SNHL. RESULTS: Of the 301 children, 68.1% had a definite or probable cause of their SNHL identified; 18.9%, 1 or more possible causes; and 31.9%, no obvious cause. A family history of SNHL or prematurity and/or complicated perinatal course was found in 28.6% of patients. Named syndromes, multiple congenital anomalies, meningitis, or prenatal maternal factors, including maternal prenatal substance abuse, were present in another 38.5%. However, syndromes commonly reported to be associated with SNHL, such as Waardenburg syndrome, were seen in less than 1% of patients. The average age at diagnosis was 3.02 years for the bilateral moderate or worse SNHL; for unilateral SNHL, the average age was 3.97 years. The most useful diagnostic study was computed tomographic scanning. CONCLUSIONS: Sensorineural hearing loss is fairly common in children. Extensive workups, often without clear direction, should be reconsidered based on the children with SNHL who otolaryngologists are now seeing. Infant screening programs, although identifying many children earlier, will also provide the opportunity to fine-tune the evaluation (ie, cytomegalovirus titers and/or cultures at birth), increasing the diagnostic yield.

Adolescent↗
PubMed1998

Inhibition of cell proliferation in head and neck squamous cell carcinoma cell lines with antisense cyclin D1.

Cyclin D1 and cyclin G are essential regulatory factors in the progression of the cell cycle from G0 through G1 and S phase. Aberrations in expression of these cyclins may lead to dysregulated cellular proliferation that could result in neoplasia. Amplification and overexpression of cyclin D1 have been observed in many human cancers, whereas cyclin G is a new cyclin recently described in osteosarcoma cells. This study was performed to determine whether these cyclins were amplified in head and neck squamous cell carcinoma (HNSCC) tumors. Polymerase chain reaction of DNA extracted from 22 HNSCC primary tumors and three HNSCC cell lines did not reveal amplification of cyclin D1 in any of the tumor samples. Southern blot analysis identified amplification of cyclin D1 in a single tumor. Amplification of cyclin G was not observed in any of the tumors by Southern blot hybridization with a cyclin G probe. HNSCC cell lines transfected with antisense cyclin D1 were tested for cell proliferation by the incorporation of 3H-thymidine into cells grown in serum-free media. By 72 hours of incubation, there was a greater than 30% reduction in proliferation of cells transfected with antisense cyclin D1 as compared with non-transfected control cells. The results indicate that cyclin D1 may play an important role in the growth and proliferation of HNSCC cells.

Adult↗
PubMed1997

Deletion analysis of the p16/CDKN2 gene in head and neck squamous cell carcinoma using quantitative polymerase chain reaction method.

BACKGROUND: Recently, the p16/CDKN2/MTS1 gene in the 9p21-22 region has been offered as a candidate tumor suppressor gene. We examined the frequency of hemizygous and homozygous deletions of p16/CDKN2 in head and neck squamous cell carcinoma (HNSCC) using a quantitative polymerase chain reaction (PCR) method. DESIGN: Twenty-one HNSCC and 12 corresponding normal DNA samples were examined for deletion of p16/ CDKN2 using PCR amplification and fluorescent quantification of DNA. All tumor and normal DNA samples were also amplified with fluorescein-labeled primers for a control DNA marker on chromosome 8p (D8S265). The ratios of the observed fluorescence of the p16/CDKN2 and 8p PCR products were compared. SETTING AND PARTICIPANTS: Patients with HNSCC scheduled to undergo surgical resection of their tumors were recruited. After the specimen was removed, a portion of the tissue was snap frozen for further DNA extraction. RESULTS: Eight tumors (38%) had p16/CDKN2-D8S265 ratios of greater than 0.75; 8 tumors (38%), from 0.25 to 0.75; and 5 tumors (24%), of less than 0.25, the average ratio in this last group being 0.06. CONCLUSIONS: These ratios suggest a higher rate of homozygous deletion than previously reported and significant probable hemizygous deletion of the p16/CDKN2 gene in HNSCC.

Carcinoma, Squamous Cell↗
PubMed1997

Suppressive factor or factors derived from head and neck squamous cell carcinoma induce apoptosis in activated lymphocytes.

Our laboratory has previously identified a soluble factor derived from head and neck squamous cell carcinoma that impairs lymphocyte proliferative responses in vitro. This study further investigates the nature of the interaction between these factors and T lymphocytes. The proliferative activity of phytohemagglutinin-stimulated peripheral blood lymphocytes and the Jurkat T-cell line was significantly suppressed (>50%) by the supernatants of 13 (41.9%) of 31 recently explanted head and neck squamous cell carcinoma samples. A characteristic morphologic appearance of these suppressed cells and ladderlike pattern of DNA fragmentation on gel electrophoresis indicated that the suppressive supernatants were inducing or predisposing T cells to apoptotic death. This apoptosis-inducing activity may be similar to that previously described in a suppressive supernatant obtained from an esophageal carcinoma cell line. These results shed further light on the mechanism behind a soluble immunosuppressive factor or factors produced by head and neck squamous cell carcinoma.

Adult↗
PubMed1995

Clinical and pathologic distinction between primary and metastatic mucosal melanoma of the head and neck.

Metastatic mucosal melanoma is extremely rare. Only 0.6% to 9.3% of patients with cutaneous malignant melanoma will have metastases to the mucosa of the upper aerodigestive tract. The records of all patients with mucosal melanoma of the head and neck at the University of California, Los Angeles Medical Center during the past 30 years were reviewed. Patients with primary tumors were separated form those with metastatic involvement from a cutaneous primary site. These two groups were compared for differences in clinical symptoms, histopathologic findings, treatment, and survival characteristics. Frequent sites of metastatic involvement included the base of tongue and nasal cavity. These arose from a variety of cutaneous sites including the trunk and extremities and, in most instances, did not arise until 2 to 7 years after the initial cutaneous lesion. Most of those with metastases to the head and neck mucosa had disseminated disease. The histopathologic distinction between the two groups is described with photomicrographs. Junctional activity in the overlying or adjacent mucosa distinguishes primary mucosal melanoma from metastatic disease, in which the overlying mucosa is usually intact. This difference is useful in determining workup and treatment options. Aggressive surgical resection is suggested in treatment of primary melanomas, whereas surgery is at best palliative in those with metastatic disease.

Adult↗
PubMed1995

Characterization of lymphocyte subpopulations in Warthin's tumor.

Cell suspensions from six Warthin's tumors (WTs) were characterized with fluorescence-labeled cell cytometry. WT lymphocyte subsets were identified with monoclonal antibodies directed against lymphocyte-associated cell antigens including T lymphocyte subsets, B lymphocytes, and natural killer (NK) cells. Results showed that T cell proportions were 58% and B cell proportions were 39%. The T cell helper:cytotoxic-suppressor ratio was 5.7:1 and the B to T cell ratio was 0.8:1. NK cells represented 1.3% of cells. When compared to peripheral blood lymphocytes (PBLs) in the same patients, statistically significant differences were noted between PBLs and WT lymphocytes in the percentage of B lymphocytes (P < .01), T cytotoxic-suppressor lymphocytes (P < .02), NK cells (P < .01), and in the ratios of B to T lymphocytes (P < .01) and T helper to T cytotoxic-suppressor lymphocytes (P < .03). Comparing these data to retrospective data on lymphocyte distribution in normal and reactive lymph nodes, the epithelial component does not appear to exert a local effect on the lymphoid component of WT.

Adenolymphoma↗
PubMedDate not supplied

Hemangiopericytoma of the head and neck.

PURPOSE: To report a series of patients with hemangiopericytoma (HP) of the head and neck, to review pathological features of these tumors, and to discuss management options. MATERIALS AND METHODS: A retrospective review of the medical records at the University of California, Los Angeles (UCLA) Medical Center in Los Angeles, CA, was done in order to identify those patients with primary HP of the head and neck, including soft tissue and mucosal sites. RESULTS: Ten patients with HP of the head and neck were identified. There was an equal sex distribution and an average age of 36 (range 10-65). Seven of the tumors arose from soft tissue sites in the head and neck, and the remaining 3 arose from the mucosa. All patients underwent wide excision of the primary lesion with a local recurrence rate of 40%. Thirty percent of patients developed metastatic lung disease 0 to 8 years after initial diagnosis. Each patient who developed metastatic disease had abundant mitoses on pathological review compared with rare or absent mitoses in the lesions that took a more benign course. CONCLUSIONS: Pathological appearance of resected HP is predictive of later metastatic potential. Long-term follow-up is necessary in patients even after radical resection because recurrence or metastasis may be delayed by many years.

Adolescent↗