Evaluation of Strategies for Reducing Vancomycin-Piperacillin/Tazobactam Incompatibility.

BACKGROUND: Drug incompatibility is defined as a physical-chemical reaction between two or more injectable drugs and that results mainly in precipitation or insolubility. Several strategies for reducing incompatibilities have been implemented empirically in intensive care units. However, these strategies have never been compared directly (and particularly in terms of the particulate load and drug mass flow rate) under standardized conditions. The objective of the present in vitro study was to evaluate the impact of various strategies for preventing incompatibility between simultaneously infused vancomycin and piperacillin/tazobactam. METHODS: An in-line filter, a dilute vancomycin solution (5 mg/mL), and an alternative saline administration line were evaluated separately. The infusion line outlet was connected to a dynamic particle counter. The antibiotic concentration was measured in an HPLC-UV assay. RESULT: The use of an in-line filter and an alternative saline administration route did not significantly reduce the particulate load caused by vancomycin-piperacillin/tazobactam incompatibility. Dilution of the vancomycin solution was associated with a significantly lower particulate load and maintenance of the vancomycin mass flow rate. DISCUSSION: It is important to systematically compare the efficacy of strategies for preventing drug incompatibility. The use of diluted vancomycin solution gave the best results in the case of vancomycin-piperacillin/tazobactam incompatibility.

Tumor bed extending to margins in breast cancer specimens after neoadjuvant chemotherapy: Incidence and clinical significance.

BACKGROUND: Pathologic examination of post-neoadjuvant chemotherapy (NAC) breast surgical specimens includes assessment of margins. It has been recommended that tumor bed (TB) changes extending to margins should be documented; however, its' incidence and clinical significance have not yet been established. The aim of our study was to gather prognostic data on this histological finding. DESIGN: We retrospectively identified all cases where TB was reported at margin. Cases where margins were also positive for invasive carcinoma or DCIS were excluded. RESULTS: From 2016 to 2019, 115 cases of NAC treated breast cancers were identified with 21 having at least one margin positive for TB after initial surgery (incidence of 18.3 %). Five cases were estrogen receptor (ER)-/HER2-, 9 were HER2+ and 7 were ER+/HER2-. Nineteen patients underwent partial mastectomy and 2 underwent total mastectomy. Nine patients had a pathological complete response (pCR).Ten cases had more than one positive margin for TB. None of the 21 patients underwent a second surgery for margin re-excision. Twenty patients received adjuvant therapy. With an average follow-up of 28.1 months, there has been one local recurrence. Four other patients developed metastatic disease, one of which died of the disease. The rates of locoregional and distant recurrence and mortality were statistically similar to those from patients whose margins were negative for TB. CONCLUSIONS: Our results suggest low risk of local recurrence when a positive margin for TB is not re-excised. Further data and follow-up will be needed to confirm the adequacy of conservative management in this setting.

Cellular Environment and Phenotypic Heterogeneity: How Data-Driven Modeling Finds the Smoking Gun.

The cellular environment modifies cellular phenotypes, in particular, the stress response phenotype, which easily exhibits high phenotypic heterogeneity due to the common characteristics of its regulatory networks. The aim of this work is to quantify and interpret the impact of collagen type I, a major component of the cellular environment, on the phenotypic heterogeneity of the cellular response. Our approach combines in an original way the monitoring of the response of a single cell and the mathematical modeling of the network. After a detailed statistical description of the phenotypic heterogeneity of the cellular response, the mathematical modeling explains how the observed changes can be explained by an induced increase in the average expression of a central protein of the regulatory network. The predictions of the data-driven model are fully consistent with the biochemical measurements performed. The framework presented here is also a new general methodology to study phenotypic heterogeneity, although we focus here on the response to proteotoxic stress in HeLa cells.

Protein level variability determines phenotypic heterogeneity in proteotoxic stress response.

Cell-to-cell variability in stress response is a bottleneck for the construction of accurate and predictive models which could guide clinical diagnosis and treatment of certain diseases, for example, cancer. Indeed, such phenotypic heterogeneity can lead to fractional killing and persistence of a subpopulation of cells which are resistant to a given treatment. The heat shock response network plays a major role in protecting the proteome against several types of injuries. Here, we combine high-throughput measurements and mathematical modeling to unveil the molecular origin of the phenotypic variability in the heat shock response network. Although the mean response coincides with known biochemical measurements, we found a surprisingly broad diversity in single-cell dynamics with a continuum of response amplitudes and temporal shapes for several stimulus strengths. We theoretically predict that the broad phenotypic heterogeneity is due to network ultrasensitivity together with variations in the expression level of chaperones controlled by the transcription factor heat shock factor 1. Furthermore, we experimentally confirm this prediction by mapping the response amplitude to chaperone and heat shock factor 1 expression levels.

Nodular Regenerative Hyperplasia: Expression Pattern of Glutamine Synthetase and a Potential Role for Hepatic Progenitor Cells.

Nodular regenerative hyperplasia (NRH) is one of the most frequent causes of noncirrhotic intrahepatic hypertension, but is a difficult histologic diagnosis. The expression of glutamine synthetase (GS) and cytokeratin 7 (CK7) has been reported to be increased in other regenerative/vascular conditions, while CK7 and BerEP4 are also markers of hepatic progenitor cells. The aims of this study were to investigate the use of GS, CK7, and BerEP4 as the potential markers for NRH. This is a retrospective case series of NRH at Centre Hospitalier de l'Universite de Montreal between 1993 and 2013. Normal liver from partial hepatectomies for tumors were used as controls. GS, CK7, CK19, and BerEP4 immunohistochemical stains were performed on all specimens. Immunohistochemical staining patterns were scored from 0 to 3+. NRH was identified in 46 samples obtained from 26 patients. Liver chemistry profile was cholestatic in 45% of the patients. In 93% of the NRH cases, there was abnormal zone 2 expression of GS. Weak panacinar GS staining was seen in all the NRH cases. Aberrant CK7 expression was present in all cases of NRH, but were not associated with cholestasis. BerEP4 was overexpressed in 47% of the NRH cases (P<0.05); all cases with diffuse BerEP4 staining also showed extensive CK7 expression (P<0.01). NRH showed increased immunohistochemical GS staining that may support its morphologic diagnosis. Our findings suggest that there is an activation of hepatic progenitor cells in NRH.

A Unique Morphological Phenotype in Chemoresistant Triple-Negative Breast Cancer Reveals Metabolic Reprogramming and PLIN4 Expression as a Molecular Vulnerability.

The major obstacle in successfully treating triple-negative breast cancer (TNBC) is resistance to cytotoxic chemotherapy, the mainstay of treatment in this disease. Previous preclinical models of chemoresistance in TNBC have suffered from a lack of clinical relevance. Using a single high dose chemotherapy treatment, we developed a novel MDA-MB-436 cell-based model of chemoresistance characterized by a unique and complex morphologic phenotype, which consists of polyploid giant cancer cells giving rise to neuron-like mononuclear daughter cells filled with smaller but functional mitochondria and numerous lipid droplets. This resistant phenotype is associated with metabolic reprogramming with a shift to a greater dependence on fatty acids and oxidative phosphorylation. We validated both the molecular and histologic features of this model in a clinical cohort of primary chemoresistant TNBCs and identified several metabolic vulnerabilities including a dependence on PLIN4, a perilipin coating the observed lipid droplets, expressed both in the TNBC-resistant cells and clinical chemoresistant tumors treated with neoadjuvant doxorubicin-based chemotherapy. These findings thus reveal a novel mechanism of chemotherapy resistance that has therapeutic implications in the treatment of drug-resistant cancer. IMPLICATIONS: These findings underlie the importance of a novel morphologic-metabolic phenotype associated with chemotherapy resistance in TNBC, and bring to light novel therapeutic targets resulting from vulnerabilities in this phenotype, including the expression of PLIN4 essential for stabilizing lipid droplets in resistant cells.

Hematologic Malignancies of the Breast: A Contemporary Series Investigating Incidence, Presentation, Accuracy of Diagnosis on Core Needle Biopsy, and Hormone Receptor Expression.

BACKGROUND: Distinguishing breast hematologic malignancies in core needle biopsies from other entities can be challenging. Misclassification as a breast carcinoma could result in inappropriate treatment. The aim of this study was to characterize the types, incidence, and helpful diagnostic features of hematologic malignancies of the breast. DESIGN: All hematologic malignancies of the breast diagnosed at our institution from 2004 to 2017 were identified. Clinical notes, imaging, and slides were reviewed. Immunohistochemical analysis of estrogen receptor α (ERα), estrogen receptor ß (ERß), and androgen receptor (AR) was performed when tissue was available. RESULTS: In all, 43 hematologic malignancies from biopsies of 37 women and 6 men were identified. Core needle biopsies (35 or 81%) were more common than excisions (8 or 19%). For 14 patients (40%), the core biopsy was the first diagnosis of a hematologic malignancy. Diagnoses included 37 lymphomas (7 primary), 4 leukemias, and 2 myelomas. There was 1 misdiagnosis of carcinoma. Low positivity for hormone receptors was observed in a minority of lymphomas. A definitive diagnosis of hematologic malignancy was made in 31 (89%) of the core needle biopsies. Only 3 patients undergoing core biopsy required excision for diagnosis. CONCLUSIONS: Most of the hematologic malignancies of the breast are currently diagnosed on core needle biopsy and 40% of patients do not have a prior history. To avoid errors, pathologists need to be aware of diagnostic features and morphologic mimics. A hematologic malignancy should be considered if tumor cells are discohesive, carcinoma in situ is absent, and hormone expression is low or absent.

Epizoochorous dispersal by ungulates depends on fur, grooming and social interactions.

The transport phase of the animal-mediated plant dispersal process is critical to dispersal effectiveness as it determines the spatial distribution of the diaspores released and their chance for further recruitment. Assessing this specific phase of the dispersal process generally requires combining diaspore retention times with the associated distances covered. Here, we specifically tested the effect of grooming behavior, interindividual contacts and ungulate fur on diaspore retention times and associated dispersal distances for the hooked diaspores of Xanthium strumarium L. experimentally attached to tamed individuals of three ungulate species. We used a comparative approach based on differing fur quality on different body zones of these three ungulates. During 6-hr sessions, we monitored for grooming and social interactions that may induce intended or inadvertent diaspore detachment. Additionally, we proposed innovative approaches to directly assessing diaspore dispersal distances by red deer in situ. Fat-tailed functions fitted diaspore retention time, highlighting the potential for long-distance dispersal events. The longer the hair, the higher the retention capacity of diaspores in the animal's fur. As predicted, donkey retained diaspores longer than red deer and dwarf goat; and we also confirmed that diaspores attached to the short hair of the head fell off more quickly than did those on the other body zones. Dwarf goat groomed more often than both red deer and donkey, but also when it carried diaspores. Up to 14% of the diaspores detached from animal fur after specific grooming behavior. We observed, in controlled conditions, for the first time and for each ungulate species, interindividual transfers of diaspores, representing 5% of the diaspores attached to animals' fur. Our results militate for incorporating animal behavior into plant dispersal modeling approaches.

Distinguishing papillary endothelial hyperplasia and angiosarcoma on core needle biopsy of the breast: The importance of clinical and radiologic correlation.

Papillary endothelial hyperplasia (PEH) is a rare non-neoplastic exuberant organizing hematoma that can closely mimic angiosarcoma due to a resemblance to malignant anastomosing blood vessels. It could be particularly difficult to distinguish PEH from angiosarcoma in breast core needle biopsies. We identified all cases of these lesions diagnosed on core needle biopsy in order to identify clinical, radiologic, and pathologic features that could prove helpful to arrive at the correct diagnosis. Four cases of PEH and 4 cases of angiosarcoma were identified. The mean age at diagnosis was 62 for PEH and 33 for primary angiosarcoma. All cases of PEH formed small masses with circumscribed or lobulated margins by imaging (mean size 0.9 cm). In 3 cases, the masses were difficult or impossible to identify after the biopsy. Angiosarcomas presented as larger masses with ill-defined margins (mean size 2.8 cm) that were unchanged in size after biopsy. PEH was surrounded by adipose tissue, whereas angiosarcoma invaded into fibrous stroma and involved lobules. The pseudopapillary structures of PEH were composed mainly of collagen, and thus, additional histologic stains for fibrin were not helpful for diagnosis. The 4 patients with PEH received no further treatment and are alive and disease-free at 2-11 years of follow-up. In contrast, the patients with angiosarcoma underwent mastectomy and chemotherapy or radiation therapy. Two of the patients with angiosarcoma died 3 years after diagnosis and the other 2 patients are alive without disease at 5 and 6 years. Therefore, distinguishing PEH and angiosarcoma is essential for appropriate management. This is the first series to compare these lesions on core needle biopsy and the first to note important clinical, imaging, and histologic differences that aid in making a diagnosis of PEH with confidence on breast core needle biopsy.

Pure Intralymphatic Invasion in the Absence of Stromal Invasion After Neoadjuvant Therapy: A Rare Pattern of Residual Breast Carcinoma.

Rarely is intralymphatic/lymph-vascular invasion (LVI) the only residual disease in the breast after neoadjuvant chemotherapy. Only 12 patients have been reported in 2 prior studies. Prognosis was poor, with only 2 patients remaining alive and disease-free. The purpose of this study was to gather more data on this pattern of residual disease. Cases in which LVI was the only residual disease in the breast were retrospectively identified. Eighteen cases were identified including 10 of 669 (1.5%) consecutive surgical cases between 2003 and 2015. The mean tumor size was 3.4 cm. Seven cancers were negative for estrogen receptor and HER2, 8 were HER2 positive, and 3 were estrogen receptor positive and HER2 negative. In 15 cases, lymph nodes were either suspicious by imaging or proven positive by biopsy. After neoadjuvant chemotherapy, 9 patients were node negative, 7 were node positive, and 2 had isolated tumor cells. Mean follow-up was 63.8 months (7 to 138 mo). Two deaths occurred in patients with positive nodes. One death occurred and 2 patients are alive with metastatic disease in the node-negative group. The remaining 13 patients are alive without disease. The outcome associated with residual LVI might not be as dismal as previously reported. Although the better outcome may be due to stage at presentation or the type of chemotherapy, it is difficult to compare the cohorts of the 3 studies. However, the death of 3 of 13 node-negative patients over the 3 studies supports not classifying residual LVI as a pathologic complete response.

Highlighting the impact of aging on type I collagen: label-free investigation using confocal reflectance microscopy and diffuse reflectance spectroscopy in 3D matrix model.

During aging, alterations of extracellular matrix proteins contribute to various pathological phenotypes. Among these alterations, type I collagen cross-linking and associated glycation products accumulation over time detrimentally affects its physico-chemical properties, leading to alterations of tissue biomechanical stability. Here, different-age collagen 3D matrices using non-destructive and label-free biophotonic techniques were analysed to highlight the impact of collagen I aging on 3D constructs, at macroscopic and microscopic levels. Matrices were prepared with collagens extracted from tail tendons of rats (newborns, young and old adults) to be within the physiological aging process. The data of diffuse reflectance spectroscopy reveal that aging leads to an inhibition of fibril assembly and a resulting decrease of gel density. Investigations by confocal reflectance microscopy highlight poor-fibrillar structures in oldest collagen networks most likely related to the glycation products accumulation. Complementarily, an infrared analysis brings out marked spectral variations in the Amide I profile, specific of the peptidic bond conformation and for carbohydrates vibrations as function of collagen-age. Interestingly, we also highlight an unexpected behavior for newborn collagen, exhibiting poorly-organized networks and microscopic features close to the oldest collagen. These results demonstrate that changes in collagen optical properties are relevant for investigating the incidence of aging in 3D matrix models.

Uterine Leiomyoma With Osteoclast-like Giant Cells.

Numerous histologic variants of uterine leiomyomas have been described. The main interest in recognizing these variants is differentiating them from leiomyosarcoma. Osteoclast-like giant cells (OLGC) have been described in association with leiomyosarcoma but to our knowledge, never with leiomyoma. We here report the case of a 58-year-old woman who underwent an elective total hysterectomy with bilateral salpingo-oophorectomy and bilateral pelvic lymphadenectomy for endometrial atypical complex hyperplasia. Multiple typical uterine leiomyoma were identified. One of them showed numerous OLGC admixed with fascicules of bland smooth muscle cells. No atypical features were identified in multiple sections of this otherwise classic uterine leiomyoma. The OLGC showed strong positivity for CD68. The patient, on follow-up, did not show any evidence of recurrent or metastatic disease. This unusual finding expands the morphologic spectrum of uterine leiomyomas. When confronted with a uterine smooth muscle cell tumor with an OLGC component, it is important to search for atypical features diagnostic of leiomyosarcoma.

Transformation of a primitive myxoid mesenchymal tumor of infancy to an undifferentiated sarcoma: a first reported case.

An 8-month-old girl underwent surgical resection of a cervical mass with histologic diagnosis of a primitive myxoid mesenchymal tumor of infancy (PMMTI). More than 5 years after the initial surgical intervention, the tumor recurred locally, with numerous distant metastases. The histologic morphology of this tumor was compatible with a diagnosis of an undifferentiated high-grade sarcoma. PMMTI is a recently described poorly differentiated fibroblastic soft-tissue tumor of infancy, of at least borderline biological behavior, characterized by local recurrence and a potential to metastasize. We present here the first case of a transformation of a PMMTI into an undifferentiated high-grade sarcoma.

Probing single-tumor cell interactions with different-age type I collagen networks by synchrotron-based Fourier transform infrared microspectroscopy.

We report here on a first study using synchrotron radiation-based Fourier transform infrared microspectroscopy and imaging to investigate HT1080 human fibrosarcoma cells grown onto different-aged type I collagen networks. Spectral images were analyzed with k-means and fuzzy C-means (FCM) clustering algorithms. K-means delineated tumor cells from their surrounding collagen networks and the latter as a function of age mainly due to specific changes in the sugar absorption region. The FCM analysis gave a better nuance of the spectral images. A progression of the biochemical information was observed upon going from the cellular compartments to the pericellular contact regions and to the intact collagens of the different age groups. Two spectral markers based on sugar and protein bands via the intensity ratio (I1032/I1655) and band area ratio (Asugar/Aamide II), showed an increase in advanced glycation endproducts (AGEs) with age. A clear-separation of the three age groups was obtained for spectra originating from the peripheral contact areas mainly due to changes in protein band intensities. The above-described markers decreased to constant levels for the three conditions indicating a masking of the biochemical information. These results hold promises to better understand the impact of age on tumor progression processes while highlighting new markers of the tumor cell invasion front.

A microscopic and macroscopic study of aging collagen on its molecular structure, mechanical properties, and cellular response.

During aging, collagen structure changes, detrimentally affecting tissues' biophysical and biomechanical properties due to an accumulation of advanced glycation end-products (AGEs). In this investigation, we conducted a parallel study of microscopic and macroscopic properties of different-aged collagens from newborn to 2-yr-old rats, to examine the effect of aging on fibrillogenesis, mechanical and contractile properties of reconstituted hydrogels from these collagens seeded with or without fibroblasts. In addition to fibrillogenesis of collagen under the conventional conditions, some fibrillogenesis was conducted alongside a 12-T magnetic field, and gelation rate and AGE content were measured. A nondestructive indentation technique and optical coherence tomography were used to determine the elastic modulus and dimensional changes, respectively. It was revealed that in comparison to younger specimens, older collagens exhibited higher viscosity, faster gelation rates, and a higher AGE-specific fluorescence. Exceptionally, only young collagens formed highly aligned fibrils under magnetic fields. The youngest collagen demonstrated a higher elastic modulus and contraction in comparison to the older collagen. We conclude that aging changes collagen monomer structure, which considerably affects the fibrillogenesis process, the architecture of the resulting collagen fibers and the global network, and the macroscopic properties of the formed constructs.

Use of biological mesh versus standard wound care in infected incisional ventral hernias, the SIMBIOSE study: a study protocol for a randomized multicenter controlled trial.

BACKGROUND: In infected incisional ventral hernias (IVHs), the use of a synthetic non-absorbable mesh is not recommended and biological meshes hold promise. However, the level of evidence for their safety and efficacy remains low. METHODS: The SIMBIOSE trial is a multicenter, phase III, randomized, controlled trial comparing the use of a biological mesh versus traditional wound care in patients with an IVH. The primary end point is 6-month infectious and/or wound morbidity. Secondary end points are wound infection and recurrent hernia rates, post-operative pain, quality of life, time to heal, reoperation need, impact of the cross-linked mesh structure, and a medico-economic evaluation. One hundred patients need to be included. RESULTS: The main results expected with biological mesh use are a significant decrease of post-operative morbidity, hernia recurrence, time to heal, and costs with an improved quality of life. CONCLUSIONS: For the first time, the impact of biological meshes in the treatment of IVHs will be evaluated in an academic, randomized, phase III trial to provide scientific evidence (NCT01594450). TRIAL REGISTRATION: ClinicalTrial.gov, NCT01594450.

Phase II/III multicentre randomised controlled trial evaluating a strategy of primary surgery and adjuvant chemotherapy versus peri-operative chemotherapy for resectable gastric signet ring cell adenocarcinomas - PRODIGE 19 - FFCD1103 - ADCI002.

BACKGROUND: A dramatic increase in the incidence of the diffuse form of gastric adenocarcinomas and particularly signet ring cell carcinomas has been observed in Western countries. Evidence is accruing that signet ring cell carcinomas may have inherent chemo resistance leaving many clinicians unsure of the benefits of delaying surgery to pursue a neoadjuvant approach. METHODS/DESIGN: PRODIGE-19-FFCD1103-ADCI002 is a prospective multicentre controlled randomised phase II/III trial comparing current standard of care of perioperative chemotherapy (2x3 cycles of Epirubicin, cisplatin, 5-fluorouracil) with a strategy of primary surgery followed by adjuvant chemotherapy (6 cycles of Epirubicin, cisplatin, 5-fluorouracil) in patients with a stage IB-III gastric signet ring cell tumour. The principal objective of the phase II study (84 patients) is to determine if the experimental arm (primary surgery followed by adjuvant chemotherapy) has sufficient interest in terms of percentage of living patients at 24 months to be evaluated in a phase III trial. If 7 or less patients in the experimental arm are alive at 24 months, phase III will not be initiated. The primary objective of phase III (230 additional patients) is to demonstrate superiority of the experimental arm in terms of overall survival. Secondary endpoints include overall survival at 36 months, disease free survival at 24 and 36 months, R0 resection rates, treatment tolerance, postoperative mortality and morbidity evaluated by Clavien-Dindo severity index, the prognostic impact of positive peritoneal cytology and the assessment of quality of life. An ancillary study will assess the emotional and cognitive impact of surgery and perioperative chemotherapy for both the patient and their partner. DISCUSSION: As inherent chemo resistance of signet ring cell tumours and delay in definitive surgery may favour tumour progression we hypothesise that a policy of primary surgery followed by adjuvant chemotherapy will improve overall survival compared to a standard perioperative chemotherapeutic strategy. This randomised phase II/III trial is the first dedicated to this histological subtype. Whilst the development of new biomarkers and targeted therapies are awaited, the results of this trial should further help in devising individualised protocols of patient care in a tumour group whose diversity increasingly demands assessment of alternative strategies. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01717924.

Probing non-enzymatic glycation of type I collagen: a novel approach using Raman and infrared biophotonic methods.

BACKGROUND: Non-enzymatic glycation is the main post-translational modification of long-life proteins observed during aging and physiopathological processes such as diabetes and atherosclerosis. Type I collagen, the major component in matrices and tissues, represents a key target of this spontaneous reaction which leads to changes in collagen biomechanical properties and by this way to tissue damages. METHODS: The current study was performed on in vitro glycated type I collagens using vibrational microspectroscopies, FT-IR and Raman, to highlight spectral features related to glycation effect. RESULTS AND CONCLUSIONS: We report a conservation of the triple-helical structure of type I collagen and noticeable variations in the exposure of proline upon glycation. Our data also show that the carbohydrate band can be a good spectroscopic marker of the glycation level, correlating well with the fluorescent AGEs formation with sugar addition. GENERAL SIGNIFICANCE: These non-invasive and label-free methods can shed new light on the spectral features of glycated collagens and represent an effective tool to study changes in the extracellular matrix observed in vivo during aging or on the advent of a pathological situation.

Microscopic structural study of collagen aging in isolated fibrils using polarized second harmonic generation.

Polarization resolved second harmonic generation (PSHG) is developed to study, at the microscopic scale, the impact of aging on the structure of type I collagen fibrils in two-dimensional coatings. A ribose-glycated collagen is also used to mimic tissue glycation usually described as an indicator of aging. PSHG images are analyzed using a generic approach of the molecular disorder information in collagen fibrils, revealing significant changes upon aging, with a direct correlation between molecular disorder and fibril diameters.