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Biomedical subjects

A B Carter

Publications and source records attributed to A B Carter.

59 records · Page 4Linked to original sources

Activation of ERK2 by respiratory syncytial virus in A549 cells is linked to the production of interleukin 8.

The airway inflammation that results from respiratory syncytial virus infection is associated with a marked increase in interleukin 8 and neutrophils in the infected sites of the lung. In this study, the relationship between production of interleukin 8, infection of A549 cells by the virus, and activation of mitogen-activated protein kinases (MAPKs) was investigated. Infection of A549 cells by the virus caused an increase on the activity of extracellular signal-regulated kinase 2 (ERK2) by about 10-fold compared with the noninfected cells. The increase in the activity of ERK2 during the viral infection was an immediate event and occurred prior to the viral replication process. PD98059, which blocks the activation of MAPK/ERK kinase 1 (MEK1), inhibited the increase in the activity of ERK2 by infection of respiratory syncytial virus by about 50% at 10 microM. Pretreatment of A549 cells with PD98059 before the viral infection also inhibited the increase in the production of interleukin 8 by 50%, but had little effect on the mRNA level. The viral infection had no effect on the activities of p38 and c-jun N-terminal kinase (JNK). These observations suggest that activation of ERK2 by respiratory syncytial virus infection may be one of the mechanisms that result in the increase of the production of interleukin 8.

Enzyme Activation↗

Recurrent intrapulmonary malignant small cell tumor of the thoracopulmonary region with metastasis to the oral cavity: review of literature and case report.

Malignant small cell tumor of the thoracopulmonary region (MSCT) was first described in 1979 and has been referred to as the Askin tumor. This malignant neoplasm is a member of the peripheral primitive neuroectodermal tumor (PPNET) family and typically involves the periosteum, soft tissue, and extrapulmonary tissue of the thoracic wall. MSCT may also involve the lung parenchyma by local extension or may arise de novo in peripheral lung tissue. Local recurrence, abdominal involvement by tumor extravasation across the diaphragm, and skeletal metastatic disease are relatively common. However, metastasis to the head and neck region and in particular to the oral cavity is extremely rare. We present a recurrent intrapulmonary MSCT with metastasis to the oral cavity in an adolescent Hispanic boy, and review the literature regarding this member of the PPNET family. Differentiation from neuroblastoma may be made based on immunoreactivity for beta 2 microglobulin and HBA71 and lack of immunoreactivity for chromogranin in PPNET and MSCT. Ultrastructural features commonly seen in MSCT and PPNET are round to ovoid tumor cells with occasional cytoplasmic processes with relatively few pleomorphic dense core granules. These tumors lack the gangliocytic and Schwann cell differentiation that is characteristic of neuroblastoma. MSCT and PPNET have a common reciprocal cytogenetic translocation [t(11;22)q(24;q12)], which is shared with Ewing's sarcoma. Prognosis in MSCT is quite dismal, with a 2-year survival of 38% and a 6-year survival of only 14%.

Adolescent↗

Dental caries in HIV-infected children: a longitudinal study.

PURPOSE: The purpose of this descriptive longitudinal clinical study was to determine primary and permanent dentition caries status in HIV-infected children, and to compare caries status with the CD4 percentage (CD4%) and immune suppression category. MATERIALS AND METHODS: 73 children up to 9 years of age with vertical HIV transmission were evaluated for caries in the primary dentition at baseline and at 6 month intervals over a 30 month period; while 19 HIV-infected children between 5 and 11 years of age had their permanent dentition evaluated for caries at baseline and at 6 month intervals over a 24 month period. Caries status was also compared with CDC CD4 percentage (> 25%, 15-24%, < 15%), and CDC immune suppression categories (immune suppression: none, moderate, severe). With primary dentition caries, comparisons were made among all children (2-9 yr-olds, N = 73), < 2 yr-olds (N = 28), 2 to 4 yr-olds (N = 20), and 5 to 9 yr-olds (N = 25), and compared with NHANES III data. Caries-free status was also determined. RESULTS: During the 30-month period, there was an almost two-fold increase in primary tooth surface caries for the 2 to 9 year-olds. Caries-free status in the primary dentition declined from 60% at baseline to 37% at the 30-month period. With 5 to 11 years-olds, DMFS and DMFT remained relatively stable, while the proportion of caries-free individuals declined from 72% at baseline to 50% at 18 months. Caries in the primary dentition was increased substantially for those in the low CDC CD4 percentage categories and CDC moderate to severe immune suppression categories. CONCLUSION: Primary dentition caries status in HIV-infected children is considerably greater than that for the US pediatric population, and increases with decreasing CD4 percentage and moderate to severe immune suppression. HIV-infected children with caries-free primary dentitions are less frequent than in the US pediatric population, and caries-free status decreases with age, lower CD4 percentage and moderate to severe immune suppression.

CD4 Lymphocyte Count↗

Detection of fungal organisms in saliva from HIV-infected children: a preliminary cytologic analysis.

PURPOSE: Fungal infections in HIV-infected individuals are associated with advancement of disease. In pediatric HIV infection, symptomatic children have a significantly higher incidence of clinical candidiasis and persistent drug-resistant candidiasis than do asymptomatic HIV-infected children. The purpose of this preliminary cytologic study was to determine the prevalence of fungal organisms in whole unstimulated saliva from children with vertically acquired HIV infection. METHODS: The subjects included 27 HIV-infected and 11 HIV-exposed, but uninfected, children. Whole unstimulated saliva was obtained for cytologic evaluation (hematoxylin and eosin, silver stains) with selected samples evaluated by electron microscopy. RESULTS: Yeast and hyphae were identified cytologically in 19% of HIV-infected (22% symptomatic HIV-infected, 11% asymptomatic HIV-infected) and 9% of HIV-exposed, but uninfected, children. Fungal organisms were found more frequently in HIV-infected with moderate (18%) and severe (27%) suppression. Fungi were more frequent with antiretroviral therapy (22%) vs no antiretroviral therapy (0%) and no antifungal therapy (20%) vs. antifungal therapy (7%). Yeast and hyphal fungal forms are more prevalent in symptomatic HIV-infection with moderate and severe suppression, and those receiving antiretroviral agents, but no antifungal medications. CONCLUSION: Fungal organisms in the saliva may reflect oral carriage or mucosal colonization, which may influence the development of clinically significant candidiasis in these immunocompromised children.

AIDS-Related Opportunistic Infections↗

Saliva collection technique for cytologic, microbiologic and viral evaluation in pediatric HIV infection.

Acquisition of saliva for biologic, immunologic and chemical analyses has been extremely difficult in infants and young children due to lack of cooperation and motor skills necessary for expectorating adequately. The purpose of this study was to investigate a technique for obtaining satisfactory quantities of whole, unstimulated saliva in the typical dental operatory setting for cytologic, microbiologic and viral evaluation, while requiring minimal cooperation and motor skills from pediatric patients. A low vacuum-assisted aspiration device was utilized to obtain samples from infants and children who were at risk for vertically acquired HIV-infection (age-range 6 mos to 8 yrs). Adequate saliva samples were collected in 175 of 196 (89 percent) attempts in 88 of 89 (99 percent) children (2.3 samples/child). Saliva was not obtained in twenty-one attempts primarily due to xerostomia (62.5 percent). Saliva sample volume obtained was variable, ranging from 1.2 to 3.6 mls with a collection time of approximately three to five minutes. Cell block preparations were made from the saliva, which allowed for cytologic evaluation of sloughed superficial squamous cells, evaluation of oral flora, and detection of yeast and hyphal fungal forms. Adequate volumes of supernate were also available for microbiologic and viral cultures, immunologic studies and PCR study for various viral agents shed in the saliva. Use of a vacuum-assisted collection device for whole unstimulated saliva in infants and young children in the dental operatory setting provides adequate saliva for multiple analyses, which may provide information regarding HIV disease status and early diagnosis of opportunistic infections.

AIDS-Related Opportunistic Infections↗