Evaluation of Nodular Splenic Lesions in 370 Small-Breed Dogs (<15 kg).

Three hundred seventy small-breed dogs (<15 kg) undergoing splenectomy for the presence of nodular splenic lesions were evaluated in a retrospective study to assess associations with breeds, malignancy, hemoperitoneum, and median survival time compared with previous studies. Data analyzed included signalment, histopathologic diagnosis, presence or absence of hemoperitoneum, breed associations, and survival times. In the current study, 44% (163/370) of dogs had nonneoplastic splenic lesions and 56% (207/370) had neoplastic lesions. Hemangiosarcoma was present in 27% (100/370) of splenic lesions. Hemoperitoneum was present in 31% (115/370) of dogs, and of this population, 66% (76/115) had malignant splenic lesions. The most common breeds were miniature schnauzers, dachshunds, and beagles, with beagles exhibiting a positive association with malignancy. The presence of hemoperitoneum was associated with malignancy. Distribution for nodular splenic lesions, correlation of hemoperitoneum to malignancy, and median survival time were similar to previous reports in large-breed dogs. Small-breed dogs who present with hemoperitoneum are 2.6 times more likely to have a diagnosis of a malignant splenic lesion. The most common small-breed dogs with nodular splenic lesions were miniature schnauzers, dachshunds, and beagles. Beagles and small-breed terriers were more likely to have malignant splenic lesions, and small-breed terriers were more likely to present with hemoperitoneum.

Distinct surveillance pathway for immunopathology during acute infection via autophagy and SR-BI.

The mechanisms protecting from immunopathology during acute bacterial infections are incompletely known. We found that in response to apoptotic immune cells and live or dead Listeria monocytogenes scavenger receptor BI (SR-BI), an anti-atherogenic lipid exchange mediator, activated internalization mechanisms with characteristics of macropinocytosis and, assisted by Golgi fragmentation, initiated autophagic responses. This was supported by scavenger receptor-induced local increases in membrane cholesterol concentrations which generated lipid domains particularly in cell extensions and the Golgi. SR-BI was a key driver of beclin-1-dependent autophagy during acute bacterial infection of the liver and spleen. Autophagy regulated tissue infiltration of neutrophils, suppressed accumulation of Ly6C+ (inflammatory) macrophages, and prevented hepatocyte necrosis in the core of infectious foci. Perifocal levels of Ly6C+ macrophages and Ly6C- macrophages were unaffected, indicating predominant regulation of the focus core. SR-BI-triggered autophagy promoted co-elimination of apoptotic immune cells and dead bacteria but barely influenced bacterial sequestration and survival or inflammasome activation, thus exclusively counteracting damage inflicted by immune responses. Hence, SR-BI- and autophagy promote a surveillance pathway that partially responds to products of antimicrobial defenses and selectively prevents immunity-induced damage during acute infection. Our findings suggest that control of infection-associated immunopathology can be based on a unified defense operation.

Polyclonality in Sclerosing Angiomatoid Nodular Transformation of the Spleen.

Sclerosing angiomatoid nodular transformation (SANT) of the spleen is a morphologically distinctive lesion. Although the clinical course of SANT is benign, its reactive or neoplastic nature remains to be clarified. Furthermore, some investigators have suggested that SANT is related to IgG4 sclerosing lesion or inflammatory pseudotumor with stromal cells positive for Epstein-Barr virus (EBV). In this study, we assessed 22 cases of SANT derived from adult women. Clinical data and follow-up information were obtained by chart review. Immunohistochemical studies for IgG4, IgG, and CD21 stains and in situ hybridization to detect EBV-encoded small RNAs were performed. We also assessed genomic DNA extracted from paraffin-embedded tissue for human androgen-receptor α gene analysis using conventional and methylation-specific polymerase chain reaction methods. The median patient age was 41.5 years (range, 25 to 82 y). Most (77%) patients presented with a single mass that was detected incidentally (59%). The mean size of the lesions was 3.8 cm (range, 1.0 to 9.0 cm). Clinical symptoms correlated with multiple lesions (P=0.043) but not lesional size (P=0.637) or location in the spleen (hilum vs. periphery, P=0.696). None of the cases had evidence of IgG4-related disease or recurred after splenectomy. The mean number of IgG4 cells was 27.7 (range, 4 to 125), and the mean IgG4/IgG ratio was 16.4% (range, 1.6% to 55.7%) with only 2 cases being >40%. Cases with higher IgG4 cells did not correlate with inflammatory pseudotumor-like morphology. No lesions were positive for EBV-encoded small RNAs, and almost all cases with informative results (n=19) showed a polyclonal pattern. We conclude that SANT is a polyclonal, reactive lesion rather than a neoplasm.

[Effect of Electroacupuncture at "Zusanli"(ST 36) on the Expression of Ghrelin/cAMP/PKA in the Jejunum in Rats with Spleen Qi Deficiency Syndrome].

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Zusanli"(ST 36) on Ghrelin/cAMP/PKA expression in the jejunum in rats with spleen qi deficiency syndrome, so as to reveal its underlying mechanism in improving energy metabolism. METHODS: Forty male SD rats were randomly divided into 4 groups:normal group, spleen qi deficiency syndrome (model) group, EA group and non-acupoint group (n=10 in each group).The model of spleen qi deficiency syndrome was established by improper diet and overstrain. EA (2 Hz/15 Hz, 0.5 mA) was applied to bilateral "Zusanli" (ST 36) in the EA group and non-acupoint in non-acupoint group for 20 min, once a day for 6 days. The pathologic changes of the jejunum tissue were detected by H&E staining. Ghrelin, ATP and cAMP levels in jejunum tissue were determined by ELISA. The expression levels of PKA protein in jejunum tissue were determined by Western blot. RESULTS: H&E staining showed that the intestinal villi of the model group were swelling, shortening and thickening, with a damaged or broken top-part in the model group, and basically restored to normal after EA treatment. ELISA results showed that the contents of Ghrelin, ATP and cAMP in the jejunum tissue were significantly lower in the model group than in the normal group (P<0.05), while significantly higher in the EA group than in the model group (P<0.05). Western blot results showed that the expression of PKA protein in the jejunum tissue was significantly lower in the model group than in the normal group (P<0.05), and significantly higher in the EA group than in the model group and non-acupoint group (P<0.05). CONCLUSIONS: EA at ST 36 can improve the morphological changes in the jejunum of spleen qi deficiency rats, which may be associated with its effects in increasing Ghrelin, ATP and cAMP contents, and up-regulating PKA expression, leading to an increase of energy metabolism and spleen qi at last.

p8 Deficiency causes siderosis in spleens and lymphocyte apoptosis in acute pancreatitis.

OBJECTIVES: The gene p8 was initially described in pancreatic tissue during acute experimental pancreatitis, a disease that is characterized by a systemic immune response. Although early reports suggested that p8 affects leukocyte migration during acute pancreatitis (AP), no studies revealing its immune-modulatory effects have been performed. METHODS: We investigated the composition of the cellular immune system in naive p8 knockout (p8(−/−)) mice and compared with matched wild-type mice during pancreatitis. RESULTS: In young mice, there were no relevant differences in the composition of peripheral and splenic CD3(+), CD3(+)CD4(+), CD3(+)CD8(+), CD11b(+)Gr-1(-), and Gr-1 cells. In mature p8(−/−) mice, increased splenic CD4CD25FoxP3 cells, spleen siderosis, and increased marginal zones in the splenic white pulp were found. During AP, peripheral and splenic CD3(+) and CD3CD4 declined stronger in the p8(−/−) mice. The spleen of the p8(−/−) mice showed severe hypoplasia of the white pulp and mild hyperplasia of the red pulp. This was associated with a significantly increased rate of apoptosis. CONCLUSIONS: We conclude that p8 has no impact on the cellular composition of the adaptive and innate immune systems in noninflammatory conditions. However, it may limit apoptosis and maintain homeostasis of the immune reaction during AP.

Congenital asplenia in mice and humans with mutations in a Pbx/Nkx2-5/p15 module.

The molecular determinants of spleen organogenesis and the etiology of isolated congenital asplenia (ICA), a life-threatening human condition, are unknown. We previously reported that Pbx1 deficiency causes organ growth defects including asplenia. Here, we show that mice with splenic mesenchyme-specific Pbx1 inactivation exhibit hyposplenia. Moreover, the loss of Pbx causes downregulation of Nkx2-5 and derepression of p15Ink4b in spleen mesenchymal progenitors, perturbing the cell cycle. Removal of p15Ink4b in Pbx1 spleen-specific mutants partially rescues spleen growth. By whole-exome sequencing of a multiplex kindred with ICA, we identify a heterozygous missense mutation (P236H) in NKX2-5 showing reduced transactivation in vitro. This study establishes that a Pbx/Nkx2-5/p15 regulatory module is essential for spleen development.

Inflammation in the avian spleen: timing is everything.

BACKGROUND: The synchrony of an organism with both its external and internal environment is critical to well-being and survival. As a result, organisms display daily cycles of physiology and behavior termed circadian rhythms. At the cellular level, circadian rhythms originate via interlocked autoregulatory feedback loops consisting of circadian clock genes and their proteins. These regulatory loops provide the molecular framework that enables the intracellular circadian timing system necessary to generate and maintain subsequent 24 hr rhythms. In the present study we examine the daily control of circadian clock genes and regulation of the inflammatory response by the circadian clock in the spleen. RESULTS: Our results reveal that circadian clock genes as well as proinflammatory cytokines, including Tnfά and IL-1ß, display rhythmic oscillations of mRNA abundance over a 24 hr cycle. LPS-induced systemic inflammation applied at midday vs. midnight reveals a differential response of proinflammatory cytokine induction in the spleen, suggesting a daily rhythm of inflammation. Exogenous melatonin administration at midday prior to LPS stimulation conveys pleiotropic effects, enhancing and repressing inflammatory cytokines, indicating melatonin functions as both a pro- and anti-inflammatory molecule in the spleen. CONCLUSION: In summary, a daily oscillation of circadian clock genes and inflammatory cytokines as well as the ability of melatonin to function as a daily mediator of inflammation provides valuable information to aid in deciphering how the circadian timing system regulates immune function at the molecular level. However, further research is needed to clarify the precise mechanisms by which the circadian clock and melatonin have an impact upon daily immune functions in the periphery.

Visceral and testicular calcifications as part of the phenotype in pseudoxanthoma elasticum: ultrasound findings in Belgian patients and healthy carriers.

Occasionally calcifications in abdominal organs, breasts and testicles have been reported in pseudoxanthoma elasticum (PXE) patients. In the present study, an ultrasound evaluation was performed of the abdomen and--in male patients--of the testicles in 17 PXE patients and 17 heterozygous carriers. Blood samples were taken to evaluate calcium load, liver and kidney function. Calcifications in liver, kidneys and spleen were detected in 59% of the patients and in 23.5% of healthy carriers. Parameters of kidney and liver function were normal in both groups, suggesting that the calcifications have no direct effect on organ function. Testicular ultrasound revealed parenchymous calcifications in all males investigated. Widespread, small hyperechogenic foci resembling testicular microlithiasis were seen. In some carriers, focal calcifications were identified. The current data suggest that visceral and testicular calcifications are part of the phenotype of PXE patients. Their presence in some of the healthy carriers are suggestive of subclinical manifestations in these relatives. The natural history and long-term effects of the parenchymal calcifications remain to be elucidated. As testicular microlithiasis may be associated with a higher risk for malignancy, regular clinical and ultrasound follow-up seems indicated in these patients.

[Expression of bcl-2 gene in spleen deficiency syndrome in colorectal carcinoma and the regulatory effect of Jianpikangfu decoction].

OBJECTIVE: To investigate the correlation between spleen deficiency syndrome in colorectal carcinoma and bcl-2 gene expression, and observe the regulatory effect of Jianpikangfu decoction. METHODS: Forty-five advanced colorectal carcinoma patients with spleen deficiency were randomized into Jianpikangfu decoction treatment group with also symptomatic treatment with western medicine and control group in which the patients were given expectant treatment with western medicine. The activity of salivary amylase and bcl-2 expression in the tumor tissues were detected before and after the treatment. RESULTS: Jianpikangfu decoction in combination with western medicine treatment produced more obvious inhibition of reduction in salivary amylase activity than exclusive western medicine treatment (t=7.822, P<0.01), and significantly lowered the positivity rate of bcl-2 expression (chi2=4.286, P<0.05) in the tumor tissues, which, however, displayed no obvious changes in response to exclusive western medicine treatment. CONCLUSION: Jianpikangfu decoction can inhibit the decrease in salivary amylase activity and regulate bcl-2 gene expression in colorectal carcinoma patients with spleen deficiency syndrome.

Somatic c-KIT activating mutation in urticaria pigmentosa and aggressive mastocytosis: establishment of clonality in a human mast cell neoplasm.

Mastocytosis is characterized by accumulations of mast cells in various organs (1). Most cases are indolent and confined to the skin, where discrete mast cell infiltrates are associated increased epidermal melanin, a clinical picture known as urticaria pigmentosa (UP). Other forms of mastocytosis combine UP with aggressive involvement of other organs or with haemotologic abnormalities (1-4). It is not known whether all forms of mastocytosis are true neoplasms or whether some might represent reactive hyperplasias (5-7). The c-KIT proto-oncogene encodes a type III receptor tyrosine kinase (KIT) that is critical to the development and survival of mast cells and melanocytes (8-11). The ligand for KIT (KL) can stimulate mast cell development, proliferation, and mediator release (9,12-17), as well as melanocyte proliferation and pigment production (18-20). To determine the role of c-KIT in the pathogenesis of mastocytosis, we examined tissue and cells isolated from a patient with UP and aggressive systemic mastocytosis with massive splenic involvement. We found a mutation that results in constitutive activation and expression of c-KIT in mast cells of both skin and spleen. This is the first in situ demonstration of an activation c-KIT mutation in neoplastic cells. It also demonstrates the clonal and neoplastic nature of this form of mastocytes.

Familial multiple mesothelial cysts of the spleen.

A 5-month-old boy who was diagnosed as having hydrops fetalis at 25 weeks' gestation had severe ascites of unknown origin. At the age 12 months, ultrasonography and computed tomography showed multiple cysts in the spleen that were increasing in size rapidly. Splenectomy resulted in complete disappearance of the ascites. These cysts were diagnosed as mesothelial cysts because the cell lining of the splenic cysts stained positively with alcian blue and cytokeratin. The boy's mother had undergone splenectomy for splenic and retroperitoneal lymphangiomas at 4 years of age. Histological reevaluation showed that the lining of her splenic cysts had the same mesothelial components as her son's. Their chromosomal assay showed normal karyotypes. Mesothelial cyst of the spleen appears similar to splenic lymphangioma morphologically; however, bleomycin and OK-432 were not effective. Familial splenic mesothelial (epidermoid) cysts have been reported in three sets of siblings, but this is the first report of their occurrence in mother and son.

Induction of perlecan gene expression precedes amyloid formation during experimental murine AA amyloidogenesis.

BACKGROUND: In a murine model of AA amyloidosis, it has been demonstrated that perlecan, the basement membrane heparan sulfate proteoglycan, is co-deposited with AA amyloid as it forms in various tissues. The objectives of this study were to determine whether the accumulation of perlecan during amyloidogenesis is associated with induction of perlecan gene expression and, if so, to define the temporal relationship of this induction to the onset of amyloid formation. EXPERIMENTAL DESIGN: Accelerated splenic AA amyloidosis was stimulated in mice by concomitant administration of subcutaneous silver nitrate as an inflammatory stimulus and amyloid-enhancing factor. A kinetic analysis of splenic perlecan mRNA levels during amyloid formation in the spleen was conducted using a reverse transcription-polymerase chain reaction assay. Amyloid deposits were detected histochemically with the Congo red stain and by immunohistochemistry using anti-AA antisera. RESULTS: Perlecan mRNA levels increased significantly during amyloidogenesis, increasing 4.1-fold within 72 hours of the amyloidogenic stimulus and subsequently falling to steady-state levels. A 2.0-fold induction of perlecan mRNA occurred by 24 hours post-stimulation, a time at which amyloid was not detectable by either histochemistry or immunohistochemistry. In contrast, control animals administered either the inflammatory stimulus or AEF alone showed no significant change in perlecan mRNA levels. CONCLUSIONS: Increased perlecan mRNA levels account, at least in part, for the accumulation of perlecan in murine splenic AA amyloid deposits. This induction of perlecan gene expression occurs before the onset of amyloid formation, supporting a role for perlecan in the earliest stages of amyloid fibrillogenesis.

Familial nonparasitic splenic cysts.

Only three times the occurrence of splenic cysts in siblings has been reported. This is the first report of a nonparasitic splenic cyst in mother and daughter. This improbable coincidence may perhaps give a better insight in the histogenesis of splenic cysts. A practical classification of nonparasitic splenic cysts is presented.

Coeficiente de endocruzamento em portadores de esquistossomose mansônica / Imbreeding coefficient in carries of Schistosoma mansoni

O coeficiente de endocruzamento (f ou de Wright) foi calculado em 1123 indivíduos de Catolândia, Bahia, área hiperendêmica da esquistossomose mansônica: 148 (13,2%) tinham o coeficiente f > 0. A forma hepatosplênica foi significantemente maior nos indivíduos com f > 0 (26,8%). Nos brancos com f > 0 o risco relativo foi de 14,1; enquanto, nos brancos com f = 0, a freqüência da hepatosplenomegalia näo diferiu dos näo-brancos com f = ou f > 0. Com este coeficiente estimou-se a probabilidade de genes aléticos iguais, com origem em ancestral comum; os resultados reforçam a hipótese da regulaçäo genética na susceptibilidade à forma hepatosplênica da esquistossomose mansônica

Solitary epidermoid splenic cysts: occurrence in sibs.

The case reports of two siblings with solitary epidermoid cysts of the spleen are presented. This improbable chance occurrence raises the possibility of a transmissible genetic defect accounting for the formation of these cysts.