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1.
Front Surg ; 9: 876818, 2022.
Article En | MEDLINE | ID: mdl-35656084

There is a paucity of data on nodular regenerative hyperplasia after liver transplant. We aim to define the clinical disease trajectory and identify predictors of outcome for this rare diagnosis. This is a retrospective review of postulated risk factors and outcome in patients with nodular regenerative hyperplasia. Patients were classified as having a late presentation if nodular regenerative hyperplasia was diagnosed > 48 months from transplant, and symptomatic if portal hypertensive symptoms were present. Forty-nine of 3,711 (1.3%) adult recipients developed nodular regenerative hyperplasia, and mortality was 32.7% with an average follow up of 84.6 months. The MELD-Na 6 months after diagnosis did not change significantly. Patients with symptomatic portal hypertension at the time of diagnosis had a significantly higher risk of mortality (51.8%) compared to patients with liver test abnormalities alone (10.5%). 44.9% of patients had no previously postulated risk factor. Anastomotic vascular complications do not appear to be the etiology in most patients. The results suggest the vast majority of patients presenting with liver test abnormalities alone have stable disease and excellent long term survival, in contrast to the 56.3% mortality seen in patients that present more than 48 months after LT with symptomatic portal hypertension at diagnosis.

2.
J Trauma Acute Care Surg ; 91(5): 820-828, 2021 11 01.
Article En | MEDLINE | ID: mdl-34039927

INTRODUCTION: Current guidelines recommend nonoperative management (NOM) of low-grade (American Association for the Surgery of Trauma-Organ Injury Scale Grade I-II) pancreatic injuries (LGPIs), and drainage rather than resection for those undergoing operative management, but they are based on low-quality evidence. The purpose of this study was to review the contemporary management and outcomes of LGPIs and identify risk factors for morbidity. METHODS: Multicenter retrospective review of diagnosis, management, and outcomes of adult pancreatic injuries from 2010 to 2018. The primary outcome was pancreas-related complications (PRCs). Predictors of PRCs were analyzed using multivariate logistic regression. RESULTS: Twenty-nine centers submitted data on 728 patients with LGPI (76% men; mean age, 38 years; 37% penetrating; 51% Grade I; median Injury Severity Score, 24). Among 24-hour survivors, definitive management was NOM in 31%, surgical drainage alone in 54%, resection in 10%, and pancreatic debridement or suturing in 5%. The incidence of PRCs was 21% overall and was 42% after resection, 26% after drainage, and 4% after NOM. On multivariate analysis, independent risk factors for PRC were other intra-abdominal injury (odds ratio [OR], 2.30; 95% confidence interval [95% CI], 1.16-15.28), low volume (OR, 2.88; 1.65, 5.06), and penetrating injury (OR, 3.42; 95% CI, 1.80-6.58). Resection was very close to significance (OR, 2.06; 95% CI, 0.97-4.34) (p = 0.0584). CONCLUSION: The incidence of PRCs is significant after LGPIs. Patients who undergo pancreatic resection have PRC rates equivalent to patients resected for high-grade pancreatic injuries. Those who underwent surgical drainage had slightly lower PRC rate, but only 4% of those who underwent NOM had PRCs. In patients with LGPIs, resection should be avoided. The NOM strategy should be used whenever possible and studied prospectively, particularly in penetrating trauma. LEVEL OF EVIDENCE: Therapeutic Study, level IV.


Drainage/adverse effects , Pancreas/injuries , Pancreatectomy/adverse effects , Postoperative Complications/epidemiology , Wounds, Nonpenetrating/surgery , Wounds, Penetrating/surgery , Adult , Conservative Treatment/standards , Conservative Treatment/statistics & numerical data , Drainage/standards , Drainage/statistics & numerical data , Female , Humans , Incidence , Injury Severity Score , Male , Middle Aged , Pancreas/surgery , Pancreatectomy/standards , Pancreatectomy/statistics & numerical data , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Practice Guidelines as Topic , Retrospective Studies , Risk Factors , Tomography, X-Ray Computed , Trauma Centers/standards , Trauma Centers/statistics & numerical data , Wounds, Nonpenetrating/diagnosis , Wounds, Penetrating/diagnosis , Young Adult
3.
Trauma Surg Acute Care Open ; 4(1): e000318, 2019.
Article En | MEDLINE | ID: mdl-31392278

BACKGROUND: The obese (body mass index, BMI > 30) have been identified as a subgroup of patients in regards to traumatic injuries. A recent study found that high-grade hepatic injuries were more common in obese than non-obese pediatric patients. This study seeks to evaluate whether similar differences exist in the adult population and examine differences in operative versus non-operative management between the obese and non-obese in blunt abdominal trauma. METHODS: Patient with trauma evaluated at an American College of Surgeons verified Level I trauma center from February 2013 to November 2016 were retrospectively reviewed. All patients aged >18 years with blunt mechanism of injury and a BMI listed in the trauma registry were included. Patients were excluded for incomplete data, including BMI or inability to grade hepatic or splenic injury. Data collected included age, gender, BMI, injury severity score, hospital length of stay, procedures on liver or spleen, and mortality. Organ injuries were scored using the American Association for the Surgery of Trauma grading scales, and were determined by either imaging or intraoperative findings. Obesity was classified as BMI > 30 compared with non-obese with BMI < 30. RESULTS: During the study period, 9481 patients were included. There were 322 spleen injuries and 237 liver injuries, with 64 patients sustaining both liver and splenic injuries. No differences existed in the percentage of high-grade hepatic or splenic injuries between the obese and non-obese. Obese patients with liver injuries were more likely to have procedural intervention than non-obese liver injuries and had higher rates of mortality. No differences were found in intervention for splenic injury between obese and non-obese. CONCLUSIONS: Contrary to prior studies on adult and pediatric patients with trauma, this study found no difference between obese and non-obese patients in severity of solid organ injury after blunt abdominal trauma in the adult population. However, there was an increased rate of procedural intervention and mortality for obese patients with liver injuries. LEVEL OF EVIDENCE: 3.

5.
Am J Surg ; 214(6): 1024-1027, 2017 Dec.
Article En | MEDLINE | ID: mdl-28941725

BACKGROUND: Recent studies have suggested higher complication and conversion to open rates for nighttime laparoscopic cholecystectomy (LC) and recommend against the practice. We hypothesize that patients undergoing night LC for acute cholecystitis have decreased hospital length of stay and cost with no difference in complication and conversion rates. METHODS: A retrospective review of patients with acute cholecystitis who underwent LC from October 2011 through June 2015 was performed. Complication rates, length of stay, and cost of hospitalization were compared between patients undergoing day cholecystectomy and night cholecystectomy. RESULTS: Complication rates and costs did not differ between the day and night groups. Length of stay was shorter in the night group (2.4 vs 2.8 days, p = 0.002). CONCLUSIONS: Performing LC for acute cholecystitis during night-time hours does not increase risk of complications and decreases length of stay.


Cholecystectomy, Laparoscopic/economics , Cholecystitis, Acute/economics , Cholecystitis, Acute/surgery , Night Care/economics , Adult , Emergencies , Female , Hospital Charges , Humans , Length of Stay/statistics & numerical data , Male , Retrospective Studies , Treatment Outcome
6.
Stem Cells Transl Med ; 6(9): 1803-1814, 2017 09.
Article En | MEDLINE | ID: mdl-28650520

Recent reports have indicated human embryonic stem cells-derived midbrain dopamine (mDA) neurons as proper cell resources for use in Parkinson's disease (PD) therapy. Nevertheless, no detailed and systematic study has been conducted to identify which differentiation stages of mDA cells are most suitable for transplantation in PD therapy. Here, we transplanted three types of mDA cells, DA progenitors (differentiated in vitro for 16 days [D16]), immature DA neurons (D25), and DA neurons (D35), into PD mice and found that all three types of cells showed high viability and strong neuronal differentiation in vivo. Both D25 and D35 cells showed neuronal maturation and differentiation toward TH+ cells and, accordingly, satisfactory behavioral functional recovery. However, transplanted D16 cells were less capable of producing functional recovery. These findings provide a valuable guideline for standardizing the differentiation stage of the transplantable cells used in clinical cell therapy for PD. Stem Cells Translational Medicine 2017;6:1803-1814.


Dopaminergic Neurons/cytology , Mesencephalon/cytology , Neural Stem Cells/cytology , Parkinson Disease/therapy , Stem Cell Transplantation/methods , Animals , Cells, Cultured , Dopaminergic Neurons/transplantation , Humans , Male , Mice , Mice, Inbred NOD , Mice, SCID , Neural Stem Cells/transplantation , Neurogenesis
7.
Med Educ Online ; 21: 31196, 2016.
Article En | MEDLINE | ID: mdl-27357909

INTRODUCTION: Empathy among medical practitioners has been shown to affect patient care and outcomes. Factors such as stress and depression are known to have a negative impact on medical student empathy. Approaches such as mindfulness, meditation, and other mind-body techniques can enhance empathy and reverse burnout symptoms. In the present study, we evaluated impact of Mind Body Medicine (MBM) course on perceived stress and empathy on first-year medical students. METHODS: Thirteen first-year medical students in total self-selected into MBM (experimental) and seven non-MBM (control) groups completed a prospective, pre- and post-test analysis, using the Jefferson Scale of Physician Empathy - Students (JSPE-S), Perceived Stress Scale (PSS), and Personal Health Questionnaire (PHQ) to evaluate empathy, stress, and depression, respectively. RESULTS: Our results showed an increase in stress, as well as a decrease in empathy, in both MBM and non-MBM groups throughout the course of the study. CONCLUSION: Our study demonstrated that the inverse relationship increased stress and decreased empathy among first-year medical students and participation in the MBM course did not attenuate the changes. However, a statistically significant rise in the depression score in the non-MBM group was not observed in the MBM group.

8.
Cell Transplant ; 25(7): 1343-57, 2016.
Article En | MEDLINE | ID: mdl-26720780

Neuronal progenitor cells (NPCs) derived from human embryonic stem cells (hESCs) are an excellent cell source for transplantation therapy due to their availability and ethical acceptability. However, the traditional method of expansion and differentiation of hESCs into NPCs in monolayer cultures requires a long time, and the cell yield is low. A microcarrier (MC) platform can improve the expansion of hESCs and increase the yield of NPCs. In this study, for the first time, we transplanted microcarrier-expanded hESC-derived NPCs into the striatum of adult NOD-SCID IL2Rgc null mice, either as single cells or as cell aggregates. The recipient mice were perfused, and the in vivo survival, differentiation, and targeted innervation of the transplanted cells were assessed by immunostaining. We found that both the transplanted single NPCs and aggregate NPCs were able to survive 1 month posttransplantation, as revealed by human-specific neural cell adhesion molecule (NCAM) and human nuclear antigen staining. Compared to the single cells, the transplanted cell aggregates showed better survival over a 3-month period. In addition, both the transplanted single NPCs and the aggregate NPCs were able to differentiate into DCX-positive immature neurons and Tuj1-positive neurons in vivo by 1 month posttransplantation. However, only the transplantation of aggregate NPCs was shown to result in mature neurons at 3 months posttransplantation. Furthermore, we found that the cell aggregates were able to send long axons to innervate their targets. Our study provides preclinical evidence that the use of MCs to expand and differentiate hESC-derived NPCs and transplantation of these cells as aggregates produce longer survival in vivo.


Cell Differentiation , Microspheres , Neural Stem Cells/cytology , Neural Stem Cells/transplantation , Animals , Cell Aggregation , Cell Proliferation , Cell Survival , Dopaminergic Neurons/cytology , Doublecortin Protein , Human Embryonic Stem Cells/cytology , Humans , Male , Mice, Inbred NOD , Mice, SCID , Neurites/metabolism , Time Factors
9.
Cytotherapy ; 17(8): 1152-65, 2015 Aug.
Article En | MEDLINE | ID: mdl-26139547

BACKGROUND AIMS: Mesenchymal stromal cells (MSCs) are being investigated as potential cell therapies for many different indications. Current methods of production rely on traditional monolayer culture on tissue-culture plastic, usually with the use of serum-supplemented growth media. However, the monolayer culturing system has scale-up limitations and may not meet the projected hundreds of billions to trillions batches of cells needed for therapy. Furthermore, serum-free medium offers several advantages over serum-supplemented medium, which may have supply and contaminant issues, leading to many serum-free medium formulations being developed. METHODS: We cultured seven MSC lines in six different serum-free media and compared their growth between monolayer and microcarrier culture. RESULTS: We show that (i) expansion levels of MSCs in serum-free monolayer cultures may not correlate with expansion in serum-containing media; (ii) optimal culture conditions (serum-free media for monolayer or microcarrier culture) differ for each cell line; (iii) growth in static microcarrier culture does not correlate with growth in stirred spinner culture; (iv) and that early cell attachment and spreading onto microcarriers does not necessarily predict efficiency of cell expansion in agitated microcarrier culture. CONCLUSIONS: Current serum-free media developed for monolayer cultures of MSCs may not support MSC proliferation in microcarrier cultures. Further optimization in medium composition will be required for microcarrier suspension culture for each cell line.


Cell Culture Techniques , Cell- and Tissue-Based Therapy/methods , Culture Media, Serum-Free , Mesenchymal Stem Cells/cytology , Cell Line , Cell Proliferation , Humans
10.
Tissue Eng Part C Methods ; 19(2): 166-80, 2013 Feb.
Article En | MEDLINE | ID: mdl-22834957

Neural progenitor cells (NPCs) derived from human induced pluripotent stem cells (hiPSCs) can be differentiated to neural cells that model neurodegenerative diseases and be used in the screening of potential drugs to ameliorate the disease phenotype. Traditionally, NPCs are produced in 2D cultures, in low yields, using a laborious process that includes generation of embryonic bodies, plating, and colony selections. To simplify the process and generate large numbers of hiPSC-derived NPCs, we introduce a microcarrier (MC) system for the expansion of a hiPSC line and its subsequent differentiation to NPC, using iPS (IMR90) as a model cell line. In the expansion stage, a process of cell propagation in serum-free MC culture was developed first in static culture, which is then scaled up in stirred spinner flasks. A 7.7-fold expansion of iPS (IMR90) and cell yield of 1.3×106 cells/mL in 7 days of static MC culture were achieved. These cells maintained expression of OCT 3/4 and TRA-1-60 and possessed a normal karyotype over 10 passages. A higher cell yield of 6.1×106 cells/mL and 20-fold hiPSC expansion were attained using stirred spinner flasks (seeded from MC static cultures) and changing the medium-exchange regimen from once to twice a day. In the differentiation stage, NPCs were generated with 78%-85% efficiency from hiPSCs using a simple serum-free differentiation protocol. Finally, the integrated process of cell expansion and differentiation of hiPSCs into NPCs using an MC in spinner flasks yielded 333 NPCs per seeded hiPSC as compared to 53 in the classical 2D tissue culture protocol. Similar results were obtained with the HES-3 human embryonic stem cell line. These NPCs were further differentiated into ßIII-tubulin⁺ neurons, GFAP⁺ astrocytes, and O4⁺ oligodendrocytes, showing that cells maintained their multilineage differentiation potential.


Cell Differentiation , Cell Division , Neurons/cytology , Pluripotent Stem Cells/cytology , Cells, Cultured , Culture Media, Serum-Free , Flow Cytometry , Humans , Immunohistochemistry , Karyotyping , Real-Time Polymerase Chain Reaction
11.
Curr Protoc Stem Cell Biol ; Chapter 1: Unit 1C.11, 2010 Sep.
Article En | MEDLINE | ID: mdl-20814936

This unit describes the routine maintenance and expansion of undifferentiated human embryonic stem cells (hESC) on cellulose microcarriers. Conventionally, hESCs have been maintained on feeder cells or extracellular matrix-coated two-dimensional tissue culture plates. The expansion of hESC on a tissue culture platform is limited by the available surface area and the requirement of repetitive subculturing to reach the required cell yield. Here, we show that expansion of hESC can be carried out in a three-dimensional suspension culture using Matrigel-coated cellulose microcarriers. hESCs from a tissue culture plate can be seeded directly onto the microcarriers; hESC microcarrier culture is passaged and expanded by mechanical dissociation of the cells without enzyme. Expansion of the culture in a 100-ml spinner flask is also described. Long-term culture of hESC on the microcarriers maintains typical pluripotent markers (OCT-4, Tra-1-60, and SSEA-4) and stable karyotype. Spontaneous differentiations of microcarrier-maintained hESCs in vitro (embryoid body formation) and in vivo (teratoma formation in SCID mouse) have demonstrated formation of the three germ layers. These protocols can also be applied equally well to human induced pluripotent stem cells.


Cell Culture Techniques/methods , Cellulose/metabolism , Embryonic Stem Cells/cytology , Microspheres , Cell Proliferation/drug effects , Cellulose/pharmacology , Collagen/pharmacology , Drug Combinations , Embryonic Stem Cells/drug effects , Embryonic Stem Cells/metabolism , Humans , Laminin/pharmacology , Microscopy, Phase-Contrast , Proteoglycans/pharmacology
12.
Stem Cell Res ; 2(3): 219-30, 2009 May.
Article En | MEDLINE | ID: mdl-19393590

The conventional method of culturing human embryonic stem cells (hESC) is on two-dimensional (2D) surfaces, which is not amenable for scale up to therapeutic quantities in bioreactors. We have developed a facile and robust method for maintaining undifferentiated hESC in three-dimensional (3D) suspension cultures on matrigel-coated microcarriers achieving 2- to 4-fold higher cell densities than those in 2D colony cultures. Stable, continuous propagation of two hESC lines on microcarriers has been demonstrated in conditioned media for 6 months. Microcarrier cultures (MC) were also demonstrated in two serum-free defined media (StemPro and mTeSR1). MC achieved even higher cell concentrations in suspension spinner flasks, thus opening the prospect of propagation in controlled bioreactors.


Cell Culture Techniques , Embryonic Stem Cells/cytology , Bioreactors , Collagen/chemistry , Culture Media, Serum-Free , Drug Combinations , Ectoderm/metabolism , Embryonic Stem Cells/metabolism , Endoderm/metabolism , Humans , Karyotyping , Laminin/chemistry , Mesoderm/metabolism , Proteoglycans/chemistry
13.
FEMS Yeast Res ; 7(1): 33-9, 2007 Jan.
Article En | MEDLINE | ID: mdl-17311582

Based on previous studies, Candida utilis pyruvate decarboxylase (PDC) proved to be a stable and high productivity enzyme for the production (R)-phenylacetylcarbinol (PAC), a pharmaceutical precursor. However, a portion of the substrate pyruvate was lost to by-product formation. To identify a source of PDC which might overcome this problem, strains of four yeasts -- C. utilis, Candida tropicalis, Saccharomyces cerevisiae and Kluyveromyces marxianus -- were investigated for their PDC biocatalytic properties. Biotransformations were conducted with benzaldehyde and pyruvate as substrates and three experimental systems were employed (in the order of increasing benzaldehyde concentrations): (I) aqueous (soluble benzaldehyde), (II) aqueous/benzaldehyde emulsion, and (III) aqueous/octanol-benzaldehyde emulsion. Although C. utilis PDC resulted in the highest concentrations of PAC and was the most stable enzyme, C. tropicalis PDC was associated with the lowest acetoin formation. For example, in system (III) the ratio of PAC over acetoin was 35 g g(-1) for C. tropicalis PDC and 9.2 g g(-1) for C. utilis PDC. The study thereby opens up the potential to design a PDC with both high productivity and high yield characteristics.


Acetone/analogs & derivatives , Candida/enzymology , Kluyveromyces/enzymology , Pyruvate Decarboxylase/metabolism , Saccharomyces cerevisiae/enzymology , Acetone/chemistry , Acetone/metabolism , Benzaldehydes/metabolism , Candida/classification , Catalysis , Industrial Microbiology/methods , Pyruvates/metabolism
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