Keeping Abreast of the Literature...

Graduate Winner: 1st Place, 2013. 26th Annual Carl Neureuther Student Book Collection Competition

Lactating in St. Louis: Attachments, Technologies, and Disparities

This dissertation uses the concept of attachments to explicate women’s breastfeeding practices and beliefs in the racially and economically segregated St. Louis, Missouri region. My analysis examines the interplay among attachments at three levels: women’s intrapersonal attachments to specific concepts of self; their attachments to the values and priorities of social groups; and attachments they form in response to larger structural and ideological forces in society. I argue that racial and socioeconomic disparities are manifested through breastfeeding praxis, so that breastfeeding serves as a lens through which these oppressions and disparities can be more fully viewed. To illuminate this, I focus specifically on three areas of inquiry within the larger topic of breastfeeding. First, I examine how constructions of good motherhood, as deployed by women themselves and by different breastfeeding professionals, interact with women’s breastfeeding practices and state policies concerning breastfeeding, as well as with wider processes of institutional racism, capitalism, and the consumer marketplace of breastfeeding. Next, I analyze the idea of breastfeeding as natural and the ways this conceptualization has been promulgated by breastfeeding experts and public health agencies, as well as the ways this is reinterpreted and complicated at the local level. Finally, I examine the impacts of new technologies such as breast pumps that shift emphasis from breastfeeding as an intimate process to breastmilk as a measurable product. This dissertation highlights the mechanisms through which capitalism and structural racism interact to create and perpetuate disparities in breastfeeding initiation and duration, which has impacts on both infant and maternal health. Based on my research findings, I call for both structural and community level changes to remediate this disparity

Fatal Disseminated Herpes Simplex in a very premature neonate

Herpes Simplex Virus infections (HSV) are ubiquitous. The neonatal HSV infection (NHSV) is rare. The incidence is estimated globally at only 10.3 per 100,000 births, but it can cause devastating disease in premature infants. Both HSV-1 and HSV-2 can be the etiologic agents in this type of vertically transmittted NHSV infection. Here we describe the pathological findings from a complete autopsy of a very low birth weight infant who succumbed to the infection despite early institution of antiviral treatment. We urge more awareness of this disease with continued surveillance; every effort should be taken to make an early diagnosis and thus prevent this devastating disease

A unique biofilm in human deep mycoses: fungal amyloid is bound by host serum amyloid P component

Background/Objectives We have demonstrated the presence of Candida cell surface amyloids that are important in aggregation of fungi and adherence to tissue. Fungal amyloid was present in invasive human candidal infections and host serum amyloid P component (SAP) bound to the fungal amyloid. SAP is a protease-resistant glycoprotein that binds avidly to amyloid and interferes with host defence, especially against bacterial pathogens for which neutrophils are important. In this study, we investigated whether biofilm of fungal amyloid and SAP was a feature of other disseminated fungal infections. Methods Tissue specimens from 15 autopsies were systematically evaluated with multiple histochemical stains including thioflavin T and Congo red (dyes that stain amyloid), as well as antibody to SAP. We studied specimens with disseminated aspergillosis, mucormycosis and coccidioidomycosis. The structure of the lesions, host inflammatory cells and the presence of fungal amyloid and SAP were determined. Results The structure of the lesions was characteristic in aspergillosis (‘starburst’) and mucormycosis (closely apposed bundles of hyphae). Host inflammatory cells were absent or few in number within these lesions. In Coccidioides lesions, host inflammation was sparse as well. Fungal amyloid was a prominent feature of all lesions along with abundant SAP bound to hyphae and spherules. Fungal amyloid and SAP perhaps contributed to persistence in caseous necrosis lesions. SAP also bound to Aspergillus and Mucorales amyloid in vitro. Conclusions A biofilm including amyloid and SAP is present in invasive fungal infections. This biofilm may dampen host defence leading to the characteristic sparse inflammatory reaction found in these infections

Fatal Disseminated Herpes Simplex in a very premature neonate

Herpes Simplex Virus infections (HSV) are ubiquitous. The neonatal HSV infection (NHSV) is rare. The incidence is estimated globally at only 10.3 per 100,000 births, but it can cause devastating disease in premature infants. Both HSV-1 and HSV-2 can be the etiologic agents in this type of vertically transmittted NHSV infection. Here we describe the pathological findings from a complete autopsy of a very low birth weight infant who succumbed to the infection despite early institution of antiviral treatment. We urge more awareness of this disease with continued surveillance; every effort should be taken to make an early diagnosis and thus prevent this devastating disease

Histological Examination in Obtaining a Diagnosis in Patients with Lymphadenopathy in Lima, Peru.

The differential diagnosis for lymphadenopathy is wide and clinical presentations overlap, making obtaining an accurate diagnosis challenging. We sought to characterize the clinical and radiological characteristics, histological findings, and diagnoses for a cohort of patients with lymphadenopathy of unknown etiology. 121 Peruvian adults with lymphadenopathy underwent lymph node biopsy for microbiological and histopathological evaluation. Mean patient age was 41 years (Interquartile Range 26-52), 56% were males, and 39% were HIV positive. Patients reported fever (31%), weight loss (23%), and headache (22%); HIV infection was associated with fever (P < 0.05) and gastrointestinal symptoms (P < 0.05). Abnormalities were reported in 40% of chest X-rays (N = 101). Physicians suspected TB in 92 patients (76%), lymphoma in 19 patients (16%), and other malignancy in seven patients (5.8%). Histological diagnoses (N = 117) included tuberculosis (34%), hyperplasia (27%), lymphoma (13%), and nonlymphoma malignancy (14%). Hyperplasia was more common (P < 0.001) and lymphoma less common (P = 0.005) among HIV-positive than HIV-negative patients. There was a trend toward reduced frequency of caseous necrosis in samples from HIV-positive than HIV-negative TB patients (67 versus 93%, P = 0.055). The spectrum of diagnoses was broad, and clinical and radiological features correlated poorly with diagnosis. On the basis of clinical features, physicians over-diagnosed TB, and under-diagnosed malignancy. Although this may not be inappropriate in resource-limited settings where TB is the most frequent easily treatable cause of lymphadenopathy, diagnostic delays can be detrimental to patients with malignancy. It is important that patients with lymphadenopathy undergo a full diagnostic work-up including sampling for histological evaluation to obtain an accurate diagnosis

Peptide Detection of Fungal Functional Amyloids in Infected Tissue

Many fungal cell adhesion proteins form functional amyloid patches on the surface of adhering cells. The Candida albicans Agglutinin-like sequence (Als) adhesins are exemplars for this phenomenon, and have amyloid forming sequences that are conserved between family members. The Als5p amyloid sequence mediates amyloid fibril formation and is critical for cell adhesion and biofilm formation, and is also present in the related adhesins Als1p and Als3p. We have developed a fluorescent peptide probe containing the conserved Als amyloid-forming sequence. This peptide bound specifically to yeast expressing Als5p, but not to cells lacking the adhesin. The probe bound to both yeast and hyphal forms of C. albicans. Δals1/Δals3 single and double deletion strains exhibited reduced fluorescence, indicating that probe binding required expression of these proteins. Additionally, the Als peptide specifically stained fungal cells in abscesses in autopsy sections. Counterstaining with calcofluor white showed colocalization with the amyloid peptide. In addition, fungi in autopsy sections derived from the gastrointestinal tract showed colocalization of the amyloid-specific dye thioflavin T and the fluorescent peptide. Collectively, our data demonstrate that we can exploit amyloid sequence specificity for detection of functional amyloids in situ

Medical image of the week: lepidic growth

Lepidic growth is most often seen in adenocarcinoma in situ (Figure A, 40x magnification). Adenocarcinoma in situ is formerly known as bronchoalveolar cell carcinoma (BAC). A similar growth pattern in a morphologically very different tumor (mucinous adenocarcinoma) is shown for comparison (Figure B, 400x). Mucinous adenocarcinoma growing on alveolar septae nearly always is invasive, so the entity of mucinous adencioarcinoma in situ practically doesn't exist, further differentiating this entity from BAC