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PURPOSE OF THE STUDY Intertrochanteric hip fractures in elderly patients are a significant cause of morbidity and mortality, with increasing incidence due to the aging population. Despite advancements in intramedullary nailing (IMN) technology, fixation failure remains a concern. This study aims to evaluate pre-and postoperative radiographic risk factors for varus collapse in geriatric intertrochanteric fractures treated with twin interlocking derotation and compression screw cephalomedullary nail (InterTAN, Smith & Nephew). MATERIAL AND METHODS This retrospective study included patients over 60 years with AO 31A1 and 31A2 intertrochanteric femur fractures treated with InterTAN at a tertiary referral center from August 2012 to August 2017. Patients with high-energy fractures, AO 31A3 fractures, or those requiring open reduction were excluded. Data on demographics, fracture classification, implant sizes, imaging studies, and follow-up were collected. Radiographic assessments included Chang’s medial cortical support concept, tip-apex distance (TAD), calcar-referenced TAD (CalTAD), neck-shaft angles (NSA), and screw placement according to Cleveland zones. Varus collapse was defined as a >5° change in NSA within three months postoperatively. Multivariate logistic regression analysis was used to identify risk factors for varus collapse. RESULTS The study included 136 patients with a mean age of 79.8 years, of whom 38.2% were male. The early postoperative tipapex distance (TAD) averaged 21.9 mm, with 30.1% of patients experiencing varus collapse greater than 5°. Positive medial cortical support (PMCS) or neutral position (NP) type reduction was highly protective against varus collapse (p < 0.001), as well as TAD less than 25 mm (p < 0.001). Additionally, the placement of screws in the central-central or central-inferior zones provided a protective effect against varus collapse (p = 0.031). Conversely, having an OTA/AO type A2.2 or A2.3 fracture significantly increased the risk of varus collapse (p = 0.030). Other factors, such as CalTAD and the nail width to medullary canal ratio, did not significantly predict varus collapse (p = 0.831 and p = 0.952, respectively). DISCUSSION Our findings align with previous studies highlighting TAD and screw placement as critical factors in preventing fixation failure. The protective effect of PMCS or NP reduction and the increased risk associated with OTA/AO type A2.2 and A2.3 fractures are noteworthy. Unlike previous studies, CalTAD was not significantly associated with varus collapse in our cohort. The study underscores the importance of surgical technique and radiographic parameters in optimizing outcomes for elderly patients with intertrochanteric fractures. CONCLUSIONS In elderly patients treated with InterTAN nails, varus collapse is infl uenced by fracture type, TAD, reduction quality, and screw placement. Ensuring a TAD <25 mm, achieving PMCS or NP reduction, and placing screws in central-central or central-inferior zones are crucial for minimizing varus collapse. These findings highlight the importance of meticulous surgical technique and radiographic assessment in managing intertrochanteric fractures in the elderly. [ABSTRACT FROM AUTHOR]

Abstract Background One-third of breast cancers display amplifications of the ERBB2 gene encoding the HER2 kinase receptor. Trastuzumab, a humanized antibody directed against an epitope on subdomain IV of the extracellular domain of HER2 is used for therapy of HER2-overexpressing mammary tumors. However, many tumors are either natively resistant or acquire resistance against Trastuzumab. Antibodies directed to different epitopes on the extracellular domain of HER2 are promising candidates for replacement or combinatorial therapy. For example, Pertuzumab that binds to subdomain II of HER2 extracellular domain and inhibits receptor dimerization is under clinical trial. Alternative antibodies directed to novel HER2 epitopes may serve as additional tools for breast cancer therapy. Our aim was to generate novel anti-HER2 monoclonal antibodies inhibiting the growth of breast cancer cells, either alone or in combination with tumor necrosis factor-α (TNF-α). Methods Mice were immunized against SK-BR-3 cells and recombinant HER2 extracellular domain protein to produce monoclonal antibodies. Anti-HER2 antibodies were characterized with breast cancer cell lines using immunofluorescence, flow cytometry, immunoprecipitation, western blot techniques. Antibody epitopes were localized using plasmids encoding recombinant HER2 protein variants. Antibodies, either alone or in combination with TNF-α, were tested for their effects on breast cancer cell proliferation. Results We produced five new anti-HER2 monoclonal antibodies, all directed against conformational epitope or epitopes restricted to the native form of the extracellular domain. When tested alone, some antibodies inhibited modestly but significantly the growth of SK-BR-3, BT-474 and MDA-MB-361 cells displaying ERBB2 amplification. They had no detectable effect on MCF-7 and T47D cells lacking ERBB2 amplification. When tested in combination with TNF-α, antibodies acted synergistically on SK-BR-3 cells, but antagonistically on BT-474 cells. A representative anti-HER2 antibody inhibited Akt and ERK1/2 phosphorylation leading to cyclin D1 accumulation and growth arrest in SK-BR-3 cells, independently from TNF-α. Conclusions Novel antibodies against extracellular domain of HER2 may serve as potent anti-cancer bioactive molecules. Cell-dependent synergy and antagonism between anti-HER2 antibodies and TNF-α provide evidence for a complex interplay between HER2 and TNF-α signaling pathways. Such complexity may drastically affect the outcome of HER2-directed therapeutic interventions.

Abstract Background Smad interacting protein-1 is a transcription factor that is implicated in transforming growth factor-β/bone morphogenetic protein signaling and a repressor of E-cadherin and human telomerase reverse transcriptase. It is also involved in epithelial-mesenchymal transition and tumorigenesis. However, genetic and epigenetic alterations of SIP1 have not been fully elucidated in cancers. In this study, we investigated mutations and promoter hypermethylation of the SIP1 gene in human hepatocellular carcinomas. Methods SIP1 expression was analyzed in HCC cell lines and primary tumors in comparison to normal and non-tumor liver tissues by using semi-quantitative RT-PCR, quantitative real-time RT-PCR and immunohistochemistry. Mutation and deletion screening of the SIP1 gene were performed by direct sequencing in HCC-derived cells. Restoration of SIP1 expression was sought by treating HCC cell lines with the DNA methyl transferase inhibitor, 5-AzaC, and the histone deacetylase inhibitor, TSA. SIP1 promoter methylation was analyzed by the combined bisulfite restriction analysis assay in in silico-predicted putative promoter and CpG island regions. Results We found that the expression of SIP1 was completely lost or reduced in five of 14 (36%) HCC cell lines and 17 of 23 (74%) primary HCC tumors. Immunohistochemical analysis confirmed that SIP1 mRNA downregulation was associated with decreased expression of the SIP1 protein in HCC tissues (82.8%). No somatic mutation was observed in SIP1 exons in any of the 14 HCC cell lines. Combined treatment with DNA methyl transferase and histone deacetylase inhibitors synergistically restored SIP1 expression in SIP1-negative cell lines. Analysis of three putative gene regulatory regions revealed tumor-specific methylation in more than half of the HCC cases. Conclusions Epigenetic mechanisms contribute significantly to the downregulation of SIP1 expression in HCC. This finding adds a new level of complexity to the role of SIP1 in hepatocarcinogenesis.

Abstract Background SLIT-ROBO families of proteins mediate axon pathfinding and their expression is not solely confined to nervous system. Aberrant expression of SLIT-ROBO genes was repeatedly shown in a wide variety of cancers, yet data about their collective behavior in hepatocellular carcinoma (HCC) is missing. Hence, we quantified SLIT-ROBO transcripts in HCC cell lines, and in normal and tumor tissues from liver. Methods Expression of SLIT-ROBO family members was quantified by real-time qRT-PCR in 14 HCC cell lines, 8 normal and 35 tumor tissues from the liver. ANOVA and Pearson's correlation analyses were performed in R environment, and different clinicopathological subgroups were pairwise compared in Minitab. Gene expression matrices of cell lines and tissues were analyzed by Mantel's association test. Results Genewise hierarchical clustering revealed two subgroups with coordinate expression pattern in both the HCC cell lines and tissues: ROBO1, ROBO2, SLIT1 in one cluster, and ROBO4, SLIT2, SLIT3 in the other, respectively. Moreover, SLIT-ROBO expression predicted AFP-dependent subgrouping of HCC cell lines, but not that of liver tissues. ROBO1 and ROBO2 were significantly up-regulated, whereas SLIT3 was significantly down-regulated in cell lines with high-AFP background. When compared to normal liver tissue, ROBO1 was found to be significantly overexpressed, while ROBO4 was down-regulated in HCC. We also observed that ROBO1 and SLIT2 differentiated histopathological subgroups of liver tissues depending on both tumor staging and differentiation status. However, ROBO4 could discriminate poorly differentiated HCC from other subgroups. Conclusion The present study is the first in comprehensive and quantitative evaluation of SLIT-ROBO family gene expression in HCC, and suggests that the expression of SLIT-ROBO genes is regulated in hepatocarcinogenesis. Our results implicate that SLIT-ROBO transcription profile is bi-modular in nature, and that each module shows intrinsic variability. We also provide quantitative evidence for potential use of ROBO1, ROBO4 and SLIT2 for prediction of tumor stage and differentiation status.

L-asparaginases (EC 3.5.1.1) are amidohydrolase enzymes that predominantly catalyze conversion of L-asparagine to L-aspartic acid and ammonia. In addition, some exhibit secondary L-glutaminase activity. Escherichia coli and Erwinia chrysanthemi L-asparaginases are widely used in the pharmaceutical industry to produce therapeutically important compounds. In the therapeutic use of enzymes, bacterial L-asparaginases can trigger immune responses, leading to a high rate of adverse effects that diminish the effectiveness of the treatment. This situation has forced scientists to search for promising L-asparaginases from new sources. Yeast L-asparaginases could be useful in reducing toxicity and enhancing efficacy but they have been poorly studied to date. Here, we characterized the yeast Lachancea thermotolerans L-asparaginase (LtASNase) purified by affinity chromatography. It has a specific activity of 313.8 U/mg and a high k cat value (312.4 s). We demonstrated through a semi-rational design that the mutations of Lys99 show varying effects on catalytic activity, with the Lys99Ala mutant increasing specific activity 3.3-fold. Furthermore, the in vitro antileukemic activity of the non-formulated form of Lys99Ala LtASNase was evaluated against SUP-B15 and REH cell lines. The results demonstrated that LtASNase exhibits significant antileukemic potential, comparable to commercial type II bacterial enzymes. The understanding of the mutant L-asparaginases examined in this study will significantly contribute to the development of new and more effective yeast-derived asparaginases., (© 2024 Wiley‐VCH GmbH.)

The possible protective effect of betulinic acid on renal ischemia/reperfusion (I/R) injury was studied. Wistar Albino rats were unilaterally nephrectomized and subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Betulinic acid (250 mg/kg, i.p.) or saline was administered at 30 min prior to ischemia and immediately before the reperfusion. Creatinine, blood urea nitrogen (BUN), lactate dehydrogenase (LDH) and TNF-alpha as well as the oxidative burst of neutrophil and leukocyte apoptosis were assayed in blood samples. Malondialdehyde (MDA), glutathione (GSH) levels, Na(+), K(+)-ATPase and myeloperoxidase (MPO) activities were determined in kidney tissue which was also analysed microscopically. I/R caused significant increases in blood creatinine, BUN, LDH and TNF-alpha. In the kidney samples of the I/R group, MDA levels and MPO activity were increased significantly, however, GSH levels and Na(+), K(+)-ATPase activity were decreased. Betulinic acid ameliorated the oxidative burst response to both formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA) stimuli, normalized the apoptotic response and most of the biochemical indices as well as histopathological alterations induced by I/R. In conclusion, these data suggest that betulinic acid attenuates I/R-induced oxidant responses, improved microscopic damage and renal function by regulating the apoptotic function of leukocytes and inhibiting neutrophil infiltration., ((c) 2009 John Wiley & Sons, Ltd.)

Three monoclonal antibodies (Mabs) were generated against p53 DNA-binding core domain. When tested by immunoprecipitation, Western blot and immunofluorescence techniques, Mab 9E4, as well as 7D3 and 6B10 reacted with both wild-type and various mutant p53 proteins. The epitopes recognized by Mabs 7D3, 9E4 and 6B10 were located respectively within the amino acid residues 211-220, 281-290 and 291-300 of human p53 protein. The epitope recognized by 9E4 Mab coincides with helix 2, also called p53 DNA binding helix, which allows the direct contact of the protein with its target DNA sequences. This antibody may be useful to study transcription-dependent and transcription-independent activities of wild-type and mutant p53 proteins.

Microsatellite instability in a subset of colorectal cancers from North America, Europe and Japan has been reported. We examined 88 colorectal cancers from Turkish patients. Five different microsatellite loci (1 mono- and 4 dinucleotide repeat regions) were tested. Eight tumors displayed replication errors (RERs) with at least 2 different markers. Right-sided tumors showed significantly higher frequency of microsatellite instability compared with left-sided tumors. The frequency of RER phenotype was slightly higher in tumors occurring in younger (<50 years old) than in older patients (13% vs. 8%), and there was no association between sex and genomic instability. The frequency of genomic instability in our study group was 9%, whereas the reported frequencies in tumors from other countries varied between 12% and 16%.

The cellular and humoral immunological parameters (leucocyte, granulocyte, lymphocyte, total T, T4, T8 lymphocyte counts, lymphoproliferative response to PHA [LP-PHA], natural killer cell activity [NKCA], IgG, IgM and IgA levels) of 20 pediatric brain tumor patients were investigated before and after chemo-(CT) and radiotherapy (RT) administered according to the UIOI-PBT-91 protocol. The T4 and T8 cell percentages and the LP-PHA values before therapy were found to be significantly diminished in comparison to values obtained from 12 healthy children (p < 0.05). In patients receiving postoperative CT, all cellular immunity parameters except T8 cell number and NKCA; IgG and IgA levels were significantly decreased after two courses of CT (p < 0.05). In 7 patients given postoperative RT, a depression in all cellular immunity parameters was observed (p < 0.05). In 6 patients treated with 2 courses of postoperative CT followed by RT administered concomitantly with low dose CDDP, there was a decrease in all cellular and humoral immunity parameters, which was not found to be significant. In 5/18 patients infectious episodes in mild to moderate severity were observed, none causing mortality. It was concluded that the UIOI-PBT-91 protocol caused cellular immunosuppression both after CT and after RT and some humoral immunosuppression after CT, but was found to be tolerable in regard to acute immunological side effects.