Medulloblastoma with extensive nodularity undergoing post-therapeutic maturation to a gangliocytoma: a case report and literature review.

We present a report of a 12-year-old boy diagnosed with medulloblastoma at 22 months of age. A gross total resection was performed followed by adjuvant systemic chemotherapy due to his young age; however, the tumor recurred locally in the posterior fossa 7 months later. The recurrent tumor was excised and he received craniospinal radiation with a boost given to the posterior fossa followed by high-dose chemotherapy. He remained disease free for approximately 10 years without major neurologic deficit and only mild cognitive impairment. A routine follow-up MRI of the brain revealed an enhancing mass. The patient underwent surgical debulking and pathological examination revealed no residual immature medulloblastoma cells but instead mature ganglion cells, consistent with a gangliocytoma. The apparent maturation of primitive medulloblastoma cells is a rare phenomenon, which may have ensued from the long-term effects of adjuvant therapies inducing advanced cellular maturation.

Characterization of the carotenoid-binding protein of the Y-gene dominant mutants of Bombyx mori.

Carotenoids play important and diverse roles in insects. Recently, we purified and partially characterized a carotenoid-binding protein (CBP) from the wild type of Bombyx mori. In this report, we utilized immunoblotting, ELISA and immunocytochemistry to further characterize and localize the expression of CBP in the larval midgut and silk gland obtained from the wild type and four naturally occurring mutants linked to carotenoids transport. CBP was expressed throughout the 5th stadium, with highest expressions on days 4-5 in the silk gland and days 3-5 in the midgut. Immunoblotting analyses demonstrated the presence of CBP along the middle part of the midgut. Microscopic immunocytochemistry demonstrated that the 33 kDa CBP was uniformly expressed along the brush border of columnar cells in the epithelium of the midgut typifying its function in aiding absorption of dietary carotenoids. Similarly, CBP was highly expressed along the distal membrane of the middle part of the silk gland demonstrating its function in uptake of carotenoids from lipophorin. When the middle silk glands and midguts of the four mutants were incubated with rabbit anti-CBP antibody, only proteins of the Y-gene dominant mutants cross reacted with the antibody further accentuating the hypothesis that the CBP is a Y-gene dependent protein.

Pulmonary histoplasmosis producing a spindle cell "pseudotumor".

Pulmonary spindle cell proliferations have been reported in association with a limited group of infectious agents. These lesions are rare and identified most often in the setting of immunosuppression. Because their appearance can simulate a spindle cell neoplasm, they are diagnostically treacherous, sometimes delaying antimicrobial therapy or resulting in unnecessary surgery. We report a case of a spindle pseudotumor of the lung resulting from Histoplasma capsulatum infection, a previously unreported cause of a spindle cell lesion in the lung. The patient was a 67-year-old woman in whom positron emission tomography-positive nodules developed in the left lung and left mediastinum. The patient had undergone renal transplantation and was receiving immunosuppressive therapy with mycophenolate, tacrolimus, and low-dose prednisone. Infection with H capsulatum was confirmed by culture of pleural effusion fluid, DNA probe analysis of the pleural fluid culture isolate, urinary Histoplasma antigen detection, and Grocott methenamine silver stains of tissue sections. To our knowledge, this is the first case of a spindle cell "pseudotumor" of the lung resulting from histoplasmosis. It highlights the importance of performing special stains for organisms when evaluating pulmonary spindle cell lesions in an immunocompromised host.

Intestinal spirochetosis in children: five new cases and a 20-year review of the literature.

Intestinal spirochetosis (IS) is an unusual infection in children, one with no standard therapeutic options. This article reports the findings on 5 new cases in conjunction with a 20-year review of the pediatric literature. The diagnosis of IS in children requires a high degree of suspicion by the physician, as many cases present with abdominal pain, chronic diarrhea, and/or hematochezia associated with a normal endoscopic examination. Silver stains (Dieterle or Whartin-Starry) are the preferred confirmatory stains on tissue sections. Giemsa (Diff-Quik) and periodic acid-Schiff stains may also be of value. Current literature favors the use of metronidazole in adult patients with IS, yet little information is available regarding treatment options in pediatric cases. This review indicates that a macrolide antibiotic with or without metronidazole may represent the best therapeutic choice for children. Further investigations are needed to determine the correlation between IS and coexisting gastrointestinal diseases and/or immunodeficiencies.