Hepatic pathology in vitamin A toxicity

This paper documents a case of vitamin A toxicity presenting with splenomegaly and ascites. The light microscopic, electron microscopic, and fluorescent findings are described in detail. The principal histopathologic finding was marked perisinusoidal fibrosis. The role of Ito cells in the storage of lipid-soluble vitamins and their subsequent transformation to fibroblasts producing collagen are discussed.     

Cholesterol embolism causing bleeding gastric ulcers

Two cases of atheromatous embolism of the small arteries of the stomach are reported. Insofar as has been ascertained, they are the first reported cases in the literature which presented symptoms of severe gastric bleeding and were found to have bleeding gastric ulcers on endoscopy. Both patients were successfully treated surgically, and their ulcers were found to be secondary to small arteriolar occlusions owing the atherosclerotic embolization. Awareness of clinicians as well as pathologists of this phenomenon in elderly males with symptoms of abdominal pain and other upper gastrointestinal symptoms unrelated to the ingestion of food is stressed. Pathophysiology of atherosclerotic emboli is also discussed.     

Filiform Polyposis of the Colon Presenting as Massive Hemorrhage: An Uncommon Complication of Crohn''s Disease

A case of localized filiform polyposis of the colon is presented. This lesion was part of a more generalized inflammatory bowel disease with clinicopathological features indicative of Crohn's disease. An unusual feature of this case was profuse rectal bleeding, initially from a solitary sigmoid ulcer and later from the area of filiform polyposis. A step by step clinicopathological follow-up emphasizing the development of filiform polyps is provided.     

The effect of femoral offset modification on gait after total hip arthroplasty

Background and purpose

A decrease of 15% in femoral offset (FO) has been reported to generate a weakness of the abductor muscle, but this has not been directly linked to an alteration of gait. Our hypothesis was that this 15% decrease in FO may also generate a clinically detectable alteration in the gait.

Patients and methods

We performed a prospective comparative study on 28 patients who underwent total hip arthroplasty (THA) for unilateral primary osteoarthritis. The 3D hip anatomy was analyzed preoperatively and postoperatively. 3 groups were defined according to the alteration in FO following surgery: a minimum decrease of 15% (9 patients), restored (14), and a minimum increase of 15% (5). A gait analysis was performed at 1-year follow-up using an ambulatory device. Each limb was compared to the contralateral healthy limb.

Results

In contrast to the “restored” group and the “increased” group, in the “decreased” group there was a statistically significant asymmetry between sides, with reduced range of motion and a lower maximal swing speed on the operated side.

Interpretation

A decrease in FO of 15% or more after THA leads to an alteration in the gait. We recommend 3-D preoperative planning because the FO may be underestimated by up to 20% on radiographs and it may therefore not be restored, with clinical consequences.The femoral offset (FO) and limb length have to be restored during total hip arthroplasty (THA) in order to improve the functional outcomes and to reduce the risk of limping, dislocation (McGrory et al. 1995, Downing et al. 2001, Bourne and Rorabeck 2002, Asayama et al. 2005, Kiyama et al. 2010), and edge loading (Sariali et al. 2010). The restoration of the FO also appears to be crucial to improve the long-term survival rates of THA. Sakalkale et al. (2001) reported that restoration of the FO reduces the wear in THA.With respect to the functional outcomes of THA, a decrease of 15% in FO has been reported to generate weakness of the abductor muscle (Asayama et al. 2005), but this has not been directly linked to an alteration of gait. Indeed, this threshold was defined under laboratory conditions using a CYBEX machine, which does not correspond to realistic activities of daily living. Our hypothesis was that a 15% decrease in the FO may also generate a clinically detectable alteration of gait.Many devices are available for analysis of gait, but most of them are constraining and cannot be used without laboratory conditions (Lamontagne et al. 2011). Some authors have proposed the use of devices for ambulatory gait analysis that can be used for long distances and under realistic daily living conditions (Aminian et al. 2004). For example, the Physilog device (Aminian et al. 2004) has been validated as an evaluation tool for the clinical assessment of patients before and after THA.We analyzed the consequences of an alteration in FO after THA for gait under realistic walking conditions.     

The crystal structure of the influenza matrix protein M1 at neutral pH: M1-M1 protein interfaces can rotate in the oligomeric structures of M1

The influenza matrix protein (M1) forms a protein layer under the viral membrane and is essential for viral stability and integrity. M1 mediates the encapsidation of the viral RNPs into the viral membrane by its membrane and RNP-binding activities. In order to understand the roles of M1-M1 protein interactions in forming the M1 layer, X-ray crystallographic studies of a M1 fragment (1-162) were carried out at neutral pH and compared with an acidic pH structure. At neutral pH the asymmetric unit was a stacked dimer of M1. A long molecular ribbon of neutral stacked dimers was formed by translation as dictated by the P1 space group. The elongated ribbon had a positively charged stripe on one side of the ribbon. A similar M1-M1 stacking interface was also found in the acidic asymmetric unit. However, within the acidic stacked dimer the molecules were not straight, but rotated in relation to each other by slightly changing the M1-M1 stacking interface. The acidic structure possessed an additional M1-M1 twofold interface. Protein docking confirmed that the M1-M1 stacking and M1-M1 twofold interfaces could be used to form a double ribbon of M1 molecules. By iterative repetition of the rotated relationship among the M1 molecules, a helix of M1 was generated. These studies suggest that M1 has the ability to form straight or bent elongated ribbons and helices. These oligomers are consistent with previous electron microscopic studies of M1, which demonstrated that isolated M1 formed elongated and flexible ribbons when isolated from what appeared to be a helical shell of M1 in the influenza virus.     

Eosinophilic venulitis of colon presenting as ileocecal mass

Reports of eosinophilic infiltration of the colon causing obstruction are few. It is even less common to find associated extensive intestinal venulitis, which is similar to and lumped together with so called Mesenteric Inflammatory Veno-Occlusive Disease (MIVOD) or Self-Limited Intestinal Venulitis. Eosinophilic necrotizing lymphadenitis, such as what we report here, has never been reported in association with this disease. A 41-year-old female presented with cramping lower abdominal pain, hematochezia, nausea, and vomiting. Computed tomography revealed the presence of the mass and thickening of the illeocecal wall. Endoscopy confirmed a cecal mass with surface ulceration suggestive of cecal adenocarcinoma. Patient underwent right hemicolectomy with the clinical and radiologic diagnosis of adenocarcinoma. Microscopic examination of the resected bowel showed an ulcerated mass in the cecum composed of markedly edematous tissue showing transmural eosinophilic infiltration and extensive eosinophilic and lymphocytic venulitis with and without thrombosis. This was associated with a necrotizing lymphadenitis.     

Hepatic Sarcoidosis

Sarcoidosis is a multisystem disease characterized by the presence of non-caseating granulomas in affected organs. Pulmonary involvement is the most common site of disease activity. However, hepatic involvement is also common in sarcoidosis, occurring in up to 70% of patients. Most patients with liver involvement are asymptomatic. Therefore, the majority of cases are discovered incidentally, frequently by the finding of elevated liver enzymes. Pain in the right upper quadrant of the abdomen, fatigue, pruritus, and jaundice may be associated with liver involvement. Portal hypertension and cirrhosis are complications linked to long-standing hepatic sarcoidosis. Liver biopsy is usually required to confirm the diagnosis. It is important to differentiate hepatic sarcoidosis from other autoimmune and granulomatous liver diseases. Not all cases of hepatic sarcoidosis require treatment. For symptomatic patients, the first line treatment includes corticosteroids or ursodeoxycholic acid. Various immunosuppressant agents can be used as second line agents. Rarely, severe cases require liver transplantation.     

Pneumatosis Cystoides Intestinalis Associated with Refractory Sprue

Pneumatosis cystoides intestinalis is a disease of unknown etiology characterized by gas-filled cysts within the bowel wall. The spectrum of gastrointestinal disorders associated with pneumatosis cystoides intestinalis is expanded by this report of a patient with refractory sprue who developed pneumatosis cystoides intestinalis and spontaneous pneumoperitoneum. Possihie pathogenetic mechanisms and the importance of the clinical diagnosis are discussed.     

Lymphokine-induced migration inhibition of murine tumor cells derived from solid neoplasms

We have previously described a noncytotoxic lymphokine, tumor migration inhibition factor, with the capacity of inhibiting the in vitro migration of a variety of tumor cells maintained by animal passage in ascitic form. In the present study, we demonstrate that it is possible to prepare viable, motile tumor cell suspensions from solid tumors and that those cells migrate better than cells that had been propagated in ascitic form. Such preparations derived from solid tumors are inhibited by tumor migration inhibition factor to a degree comparable to that achieved with cells from ascitic tumors. Comparative studies utilizing a methylcholanthrene-induced fibrosarcoma as well as solid and ascitic forms of P815 mastocytoma and Ehrlich tumor demonstrate that responsiveness to tumor migration inhibition factor is not merely a property conferred upon tumor cells by prior animal passage in suspension. These results provide a further suggestion that the capacity for lymphokine-induced migration inhibition is a general property of tumor cells. This in turn raises the possibility that this capacity might vary in a predictable manner with malignant potential.