Open inguinal hernia repair outcomes in liver transplant recipients versus patients with cirrhosis.

PURPOSE: Patients with liver cirrhosis (LC) are at an increased risk for postoperative complications after open inguinal hernia repair (OIHR). It is possible that orthotopic liver transplant (OLT) recipients may have better outcomes, given reversal of liver failure pathophysiology. Therefore, we sought to compare mortality risk, complications, length of stay (LOS), and cost associated with OIHR in OLT recipients versus LC. METHODS: From the National Inpatient Sample (NIS), using ICD-9 codes, we found 83 OLT recipients and 764 patients with LC who underwent OIHR between 2002 and 2014. We used logistic, negative binomial, and multiple linear regression models to compare peri-operative mortality risk, postoperative complications, and LOS, and cost associated with OIHR in OLT recipients versus LC patients. Models were adjusted for patient demographic and clinical characteristics, and hospital factors. RESULTS: OLT recipients were younger (58 vs 61, p = 0.02), more likely to be privately insured (42.0% vs 24.6%, p = 0.006), less likely to have ascites at time of surgery (5.1% vs 18.9%, p = 0.003), and have surgery at large (84.3% vs 65.2%, p = 0.01) and teaching hospitals (84.2% vs 47.9%, p < 0.001). There were no mortalities among OLT recipients, but 19 (2.5%) deaths among LC patients. OLT recipients had a similar risk of overall complications (adjusted odds ratio aOR = 0.71 1.30 2.41) and hospital-associated costs (adjusted cost ratio = 0.71 0.88 1.09). However, LOS was significantly different with OLT recipients having shorter LOS (adjusted LOS ratio = 0.56 0.70 0.89). CONCLUSION: Delaying OIHR in patients with LC until after OLT decreases LOS and may carry decreased mortality.

Xerocomellus (Boletaceae) in western North America.

Understanding diversity in the genus Xerocomellus in western North America has been obscured by morphological variability, widespread use of species epithets typified by specimens from Europe and eastern North America, misunderstood phylogenetic relationships, and species complexes. We collected extensively and used genetic and morphological data to establish the occurrence of ten Xerocomellus species in western North America. We generated ITS sequences from five type collections and from vouchered representative collections to clarify our understanding of existing species concepts. We describe three new species (Xerocomellus atropurpureus, X. diffractus, and X. salicicola) and propose two new combinations (X. amylosporus and X. mendocinensis), transfer Boletus coccyginus to Hortiboletus, and provide a dichotomous key to species of Xerocomellus in western North America.

New species of Entolomataceae from Cameroon.

Six species of Entoloma (Entolomataceae, Agaricales, Basidiomycota) are described from recent Cameroonian collections: E. bisterigmatum, E. brunneoloaurantiacum, E. djaense, E. intricatum, E. versiforme, and E. parvistellatum.These species occur in tropical rainforests dominated by ectomycorrhizal trees in the genera Gilbertiodendron and Uapaca. Data on macromorphology, micromorphology, DNA sequences, habitat and comparisons with similar taxa are provided for each. This is the first contemporary taxonomic work on the Entolomataceae from Cameroon.

The maximal cytoprotective function of the heat shock protein 27 is dependent on heat shock protein 70.

Endogenous heat shock proteins (HSPs) 70 and 25/27 are induced in renal cells by injury from energy depletion. Transfected over-expression of HSPs 70 or 27 (human analogue of HSP25), provide protection against renal cell injury from ATP deprivation. This study examines whether over-expressed HSP27 depends on induction of endogenous HSPs, in particular HSP70, to afford protection against cell injury. LLC-PK1 cells transfected with HSP27 (27OE cells) were injured by ATP depletion for 2h and recovered for 4h in the presence of HSF decoy, HSP70 specific siRNA (siRNA-70) and their respective controls. Injury in the presence of HSF decoy, a synthetic oligonucleotide identical to the heat shock element, the nuclear binding site of HSF, decreased HSP70 induction by 80% without affecting the over-expression of transfected HSP27. The HSP70 stress response was completely ablated in the presence of siRNA-70. Protection against injury, provided by over-expression of HSP27, was reduced by treatment with HSF decoy and abolished by treatment with siRNA-70. Immunoprecipitation studies demonstrated association of HSP27 with actin that was not affected by either treatment with HSF decoy or siRNA. Therefore, HSP27 is dependent on HSP70 to provide its maximal cytoprotective effect, but not for its interaction with actin. This study suggests that, while it has specific action on the cytoskeleton, HSP 25/27 must have coordinated activity with other HSP classes, especially HSP70, to provide the full extent of resistance to injury from energy depletion.

Embryoid body formation of human amniotic fluid stem cells depends on mTOR.

Human amniotic fluid stem cells (hAFSCs) harbor high proliferative capacity and high differentiation potential and do not raise the ethical concerns associated with human embryonic stem cells. The formation of three-dimensional aggregates known as embryoid bodies (EBs) is the principal step in the differentiation of pluripotent embryonic stem cells. Using c-Kit-positive hAFSC lines, we show here that these stem cells harbor the potential to form EBs. As part of the two kinase complexes, mTORC1 and mTORC2, mammalian target of rapamycin (mTOR) is the key component of an important signaling pathway, which is involved in the regulation of cell proliferation, growth, tumor development and differentiation. Blocking intracellular mTOR activity through the inhibitor rapamycin or through specific small interfering RNA approaches revealed hAFSC EB formation to depend on mTORC1 and mTORC2. These findings demonstrate hAFSCs to be a new and powerful biological system to recapitulate the three-dimensional and tissue level contexts of in vivo development and identify the mTOR pathway to be essential for this process.

mTOR phosphorylated at S2448 binds to raptor and rictor.

In mammalian cells, the mammalian target of rapamycin (mTOR) forms an enzyme complex with raptor (together with other proteins) named mTOR complex 1 (mTORC1), of which a major target is the p70 ribosomal protein S6 kinase (p70S6K). A second enzyme complex, mTOR complex 2 (mTORC2), contains mTOR and rictor and regulates the Akt kinase. Both mTORC1 and mTORC2 are regulated by phosphorylation, complex formation and localization. So far, the role of p70S6K-mediated mTOR S2448 phosphorylation has not been investigated in detail. Here, we report that endogenous mTOR phosphorylated at S2448 binds to both, raptor and rictor. Experiments with chemical inhibitors of the mTOR kinase and of the phosphatidylinositol-3-kinase revealed that downregulation of mTOR S2448 phosphorylation correlates with decreased mTORC1 activity but can occur decoupled of effects on mTORC2 activity. In addition, we found that the correlation of the mTOR S2448 phosphorylation status with mTORC1 activity is not a consequence of effects on the assembly of mTOR protein and raptor. Our data allow new insights into the role of mTOR phosphorylation for the regulation of its kinase activity.

CDKs as therapeutic targets for the human genetic disease tuberous sclerosis?

The tuberous sclerosis gene 2 product tuberin is an important regulator of the mammalian target of rapamycin (mTOR). In addition, tuberin is known to bind to the cyclin-dependent kinase (CDK) inhibitor p27(Kip1) (p27) and to regulate its stability and localization via mTOR-independent mechanisms. Recently, evidence has been provided that tuberin also affects p27 localization via regulating mTOR's potential to activate the serum- and glucocorticoid-inducible kinase (SGK1) to phosphorylate p27. Taken together, these findings strengthen the argument that besides mTOR-inhibitors, such as rapamycin analogues, p27 and CDKs could also be considered targets for hamartoma therapeutics in tuberous sclerosis.

Tuberin, p27 and mTOR in different cells.

Mutations in the genes TSC1 or TSC2 cause the autosomal dominantly inherited tumor suppressor syndrome tuberous sclerosis, which is characterized by the development of tumors, named hamartomas, in different organs. The TSC gene products, hamartin and tuberin, form a complex, of which tuberin is assumed to be the functional component. Both, hamartin and tuberin have been implicated in the control of the cell cycle by activating the cyclin-dependent kinase inhibitor p27 and in cell size regulation by inhibiting the mammalian target of rapamycin (mTOR) a regulator of the p70 ribosomal protein S6 kinase (p70S6K) and its target the ribosomal protein S6. The tuberin/hamartin complex was shown to protect p27 from protein degradation. Within the mTOR signaling pathway tuberin harbors GTPase activating (GAP) potential toward Rheb, which is a potent regulator of mTOR. In this study, we have analyzed the protein levels of tuberin, p27, cyclin D1, mTOR and phospho mTOR Ser2448 (activated mTOR), S6 and phospho S6 Ser240/244 (activated S6) and as controls alpha-tubulin and topoisomerase IIbeta, in ten different cells, including primary normal cells, immortalized and transformed cell lines.

Skp2 inversely correlates with p27 and tuberin in transformed cells.

The cyclin-dependent kinase inhibitor p27Kip1 (p27) is a major gatekeeper of the mammalian cell cycle progression known to be regulated by both, its subcellular localization and its degradation. To allow entrance into S phase and thereby mammalian cell cycle progression p27 must be degraded by a skp2-containing E3 ubiquitin ligase whose task is to target p27 for degradation by the proteasome. The tumor suppressor gene product tuberin directly binds to p27 and protects it from degradation via skp2. Whereas, p27 and tuberin are known to be localized to both, the cytoplasm and the nucleus, the localization of skp2 remained elusive. Here we demonstrate that skp2 is a cytoplasmic and nuclear protein. In addition we found an inverse correlation of the endogenous protein levels of skp2 with p27 and tuberin in different transformed cells and under different growth conditions. These data allow new important insights into this molecular network of cell cycle control.

Human amniotic fluid stem cells: a new perspective.

The discovery of amniotic fluid stem cells initiated a new and very promising field in stem cell research. In the last four years amniotic fluid stem cells have been shown to express markers specific to pluripotent stem cells, such as Oct-4. Due to their high proliferation potential, amniotic fluid stem cell lineages can be established. Meanwhile, they have been shown to harbor the potential to differentiate into cells of all three embryonic germ layers. It will be a major aim for the future to define the potential of this new source of stem cells for therapies related to specific diseases.

A single dose of pegylated leridistim significantly improves neutrophil recovery in sublethally irradiated rhesus macaques.

Leridistim, a member of the myelopoietin family of dual receptor agonists that binds interleukin-3 and G-CSF receptors, has been shown to enhance hematopoietic activity in rhesus monkeys above that observed with either cytokine alone or in combination. This study demonstrated the ability of a pegylated form of leridistim (peg-leridistim), administered s.c., as a single- or two-dose regimen separated by 4 or 7 days, to significantly improve neutrophil recovery following radiation-induced myelosuppression. Rhesus macaques were total body x-irradiated (250 kVp, TBI) to 600 cGy. Following TBI, two groups received peg-leridistim (n = 5) or leridistim (n = 4) at a dose of 600 microg/kg on day 1, while two other groups (both n = 4) received peg-leridistim at 200 microg/kg on day 1 and day 4, or day 1 and day 7. The irradiation controls (n = 7) received 0.1% autologous serum for 18 days. All peg-leridistim treatment schedules significantly improved all neutrophil-related parameters following TBI as compared with nontreated controls and were equivalent in effect when compared among themselves. Administration of a single high dose or two separate lower doses of peg-leridistim significantly improved neutrophil regeneration, in a manner equal to that of conventional daily or abbreviated every-other-day administration of leridistim in this nonhuman primate model of severe myelosuppression.

Promegapoietin, a family of chimeric growth factors, supports megakaryocyte development through activation of IL-3 and c-Mpl ligand signaling pathways.

OBJECTIVE: The signaling pathways induced by promegapoietin (PMP), a family of chimeric growth factors that activate the human IL-3 and c-Mpl receptors, were investigated. METHODS: The biological activity of PMP was examined by receptor binding, cell proliferation, ex vivo expansion of hematopoietic progenitor cells, and in vivo production of platelets. The activation of signaling pathways was examined by Western blot and Northern blot analyses. RESULTS: Two PMP molecules, PMP-1 and PMP-1a, induced proliferation of cells expressing the IL-3 receptor, c-Mpl, or both receptors and bound to the IL-3 receptor and c-Mpl with high affinity. Ex vivo expansion assays using human bone marrow CD34(+) cells suggested that PMP-1 induced greater total cellular expansion as well as expansion of CD41(+) megakaryocytic precursor cells than IL-3 or c-Mpl ligand alone. Subcutaneous administration of 50 microg/kg of PMP-1 for 10 days to rhesus monkeys resulted in increased platelet production in vivo from a baseline of 357 +/- 45 x 10(3) cells/mL to 1376 +/- 151 x 10(3) cell/mL. PMP-1 induced phosphorylation of the beta(c) subunit of IL-3 receptor and c-Mpl, JAK2, and STAT5b, but not STAT3. PMP-1 induced greater expression of Pim-1, c-Myc, and cyclin D2 than did either an IL-3 receptor agonist or c-Mpl receptor agonist alone. The magnitude of induction of early response genes was similar for PMP and the coaddition of IL-3 receptor agonist and c-Mpl receptor agonist. CONCLUSION: PMP combines the biological activities of IL-3 and c-Mpl ligand in a single molecule that can simultaneously activate signaling pathways induced by both these ligands.

Promegapoietin-1a, an engineered chimeric IL-3 and Mpl-L receptor agonist, stimulates hematopoietic recovery in conventional and abbreviated schedules following radiation-induced myelosuppression in nonhuman primates.

Promegapoietin-1a (PMP-1a), a multifunctional agonist for the human interleukin 3 and Mpl receptors, was evaluated for its ability to stimulate hematopoietic reconstitution in nonhuman primates following severe radiation-induced myelosuppression. Animals were total body x-irradiated (250 kVp) to 600 cGy total midline tissue dose. PMP-1a was administered s.c. in several protocols: A) daily (50 microg/kg) for 18 days; B) nine doses (5 microg/kg) every other day for 3 weeks; C) a single high dose (100 microg/kg) at 20 hours, or D) a single high dose (100 microg/kg) at 1 hour following TBI. The irradiation controls received 0.1% autologous serum for 18 consecutive days. Hematopoietic recovery was assessed by bone marrow clonogenic activity, peripheral blood cell nadirs, duration of cytopenias, time to recovery to cellular thresholds, and requirements for clinical support. PMP-1a, irrespective of administration schedule, significantly improved all platelet-related parameters: thrombocytopenia was eliminated, the severity of platelet nadirs was significantly improved, and recovery of platelet counts to > or =20,000/miccrol was significantly reduced in all PMP-1a-treated cohorts. As a consequence, all PMP-1a-treated cohorts were transfusion-independent. Neutrophil regeneration was augmented in all treatment schedules. Additionally, all PMP-1a-treated cohorts showed an improvement in red blood cell nadir and recovery. PMP-1a in conventional or abbreviated schedules induced significant thrombopoietic regeneration relative to the control cohort, whereas significant improvement in neutrophil recovery was schedule-dependent in radiation-myelosuppressed nonhuman primates.

Clinical course and outcome for children with multicystic dysplastic kidneys.

The purpose of this study was to evaluate the clinical course and outcome for children with multicystic dysplastic kidney (MCDK) disease and to non-invasively predict which of these patients are at significant risk for developing urinary tract infection (UTI) and renal insufficiency. Patients were divided, on the basis of postnatal physical examination and renal ultrasonography, into simple or complex MCDK. Simple MCDK was defined as unilateral renal dysplasia without additional genitourinary (GU) abnormalities. Complex MCDK included patients with bilateral renal dysplasia or unilateral renal dysplasia with other GU abnormalities. The designation as simple or complex MCDK was independent of reflux, since routine voiding cystourethrography (VCUG) was not performed. The charts of all patients with the diagnosis of MCDK disease seen from August 1995 to March 1999 at Yale University School of Medicine were examined to determine: (1) if UTI had occurred and (2) the level of renal function at last follow-up. Thirty-five patients were evaluated: 28 (80%) patients had unilateral MCDK, 7 (20%) were bilateral, and 14 (40%) had associated GU anomalies. Overall, 21 patients had unilateral MCDK without GU abnormalities (simple MCDK), while 14 had complex MCDK. The final outcome for patients with simple MCDK was quite good, with normal renal function and compensatory hypertrophy of the contralateral kidney in all patients. Although the patients with simple MCDK did not have routine VCUG or prophylactic antibiotics, the development of UTI was infrequent, damage to the contralateral kidney did not occur, and renal function was well preserved. In contrast, patients with bilateral disease or associated GU anomalies had a higher incidence of UTI and progression to renal failure. Complex MCDK was associated with a worse outcome (50% chronic renal insufficiency or failure).

Fibromatosis of the head and neck: a challenging lesion.

Fibromatosis is a histologically benign fibrous neoplasm that arises from the musculoaponeurotic tissues of the body. It can have significant morbidity when it occurs in the head and neck region because of the proximity of vital structures. This review article considers the etiology, demographics, pathology, natural history, and various treatment modalities for this lesion. Therapeutic guidelines are provided.

Bacteriology of nontraumatic maxillary sinus mucoceles versus chronic sinusitis.

OBJECTIVE: To compare the bacteriology of maxillary sinus mucoceles to chronic sinusitis and understand the pathogenesis of nontraumatic maxillary sinus mucoceles (NTMSM). STUDY DESIGN: Retrospective review. METHODS: Review of intraoperative bacteriology culture results obtained in patients with NTMSM. Patients with history of facial trauma or previous paranasal sinus surgery were not included in the study. The results were compared to intraoperative cultures obtained from patients with chronic sinusitis (CS). RESULTS: The study groups consisted of 16 patients with NTMSM (9 male and 7 female patients) and 211 patients with CS (86 male and 125 female patients). Cultures in the NTMSM group were positive in 7 of 16 patients (44%) (four cultures had more than one isolate). There was no growth in cultures of 9 patients (56%). On the other hand, cultures in 176 patients with CS (83%) grew organisms (42 cultures had more than one isolate); there was no growth in 35 of 211 patients (17%) (P = .0007). The cultures grew aerobic bacteria in 7 of 16 (44%) and 160 of 211 (76%) patients of the NTMSM and CS groups, respectively. Anaerobic bacteria were detected in cultures of 2 of 16 patients (12.5%) with NTMSM compared with 13 of 211 patients (6.2%) in the CS group (P = .286). The most common pathogenic aerobe in the NTMSM group was alpha-hemolytic Streptococcus, while Staphylococcus aureus was the most common in the CS group. CONCLUSION: The bacteriology of maxillary sinus mucoceles is different from that of CS. The majority of patients with mucoceles have sterile intraoperative cultures. The data do not support infection as the main origin of NTMSM.

Outcomes of septoplasty.

A prospective nonrandomized study of consecutive patients presenting to the Massachusetts Eye and Ear Infirmary for septoplasty was conducted to evaluate patient-based outcome. Patients received statistically validated measures of general health status (Short Form-12) and nasal specific health (Nasal Health Survey) before and 6 and 12 months after surgery. Multiple perioperative patient- and surgeon-dependent treatment variables were also evaluated to determine the impact on outcome. A total of 161 patients were entered into the study, and 93 were available for statistical analysis. At 9 months the mean follow-up (range 6-12 months), both symptom and medication subscores of the Nasal Health Survey, and the total score demonstrated significant improvement (P < 0.05); 71% of patients had clinically significant improvement as determined by at least a 50% decrease in duration of nasal symptoms. Measures of general health did not differ significantly from normative values at baseline and did not change after surgical intervention. Predictor analysis revealed that female gender and a history of previous nasal surgery predicted worse outcome.