Implications of humeral short-stem diametral sizing on implant stability

Background

Shoulder arthroplasty humeral stem design has evolved to include various shapes, coatings, lengths, sizes, and fixation methods. While necessary to accommodate patient anatomy characteristics, this creates a surgical paradox of choice. The relationship between the surgeon's selection of short-stem implant size and construct stiffness, resistance to subsidence and micromotion has not been assessed.

Methods

Eight paired cadaveric humeri were reconstructed with surgeon-selected (SS) and 2-mm diametrically larger (SS+2) short-stemmed press-fit implants. Each reconstruction was subjected to 2000 cycles of 90° forward flexion loading, and stem subsidence and micromotion were measured using optical tracking. Compressive stiffness of the stem-bone reconstruction was then assessed by applying a load in-line with the stem axis that resulted in 5 mm of stem subsidence.

Results

Increasing stem size by 2 mm resulted in the construct stiffness more than doubling compared to SS stems (-741 ± 243 N/mm vs. -334 ± 120 N/mm; P = .003; power = 0.971). These larger stems also subsided significantly less than their SS counterparts (SS: 1.2 ± 0.6 mm; SS+2: 0.5 ± 0.5 mm; P = .029; power = 0.66), though there were no significant changes in micromotion (SS: 169 ± 59 μm; SS+2: 187 ± 52 μm; P = .506; power = 0.094).

Conclusions

The results of this study highlight the importance of proper short-stem sizing, as a relatively small 2 mm increase in diametral size was observed to significantly impact construct stiffness, which could increase the risk of stress shielding and implant loosening. Future work should focus on developing tools that objectively quantify bone quality and aid surgeons in selecting the appropriate size short-stem humeral implants for a particular patient.

Magnetic Shielding Analysis of Bonding in [1.1.1]Propellane

The bonding in [1.1.1]propellane, bicyclo[1.1.0]butane, bicyclo[1.1.1]pentane, tetrahedrane, and cyclopropane is investigated by analyzing changes in the off-nucleus isotropic magnetic shielding within the space surrounding each of these molecules and, for [1.1.1]propellane, by examining also the diamagnetic and paramagnetic contributions to this shielding. Any shielding arising from the two "exo" sp³-like hybrid atomic orbitals on the bridgehead carbon atoms that have been used to support the idea of an inverted bond between these two atoms is found to be almost entirely contained within the [1.1.1]propellane cage and to contribute to a strongly shielded central region. This strongly shielded region suggests the establishment of a mainly covalent bonding interaction involving all carbon atoms that cannot be straightforwardly decomposed into contributions from individual carbon-carbon bonds. The emergence of the strongly shielding central region is traced by comparing the shielding variations in and around molecules with one three-membered carbon ring (cyclopropane), two fused three-membered carbon rings (bicyclo[1.1.0]butane), and three fused three-membered carbon rings ([1.1.1]propellane).

930 Impact of the COVID-19 Pandemic on Higher General Surgical Training – A West of Scotland Experience

Introduction

COVID-19 pandemic has caused significant disruption in all aspects of training. Our aim was to explore the degree of impact caused by the pandemic on higher general surgical trainees.

Method

All higher general surgical trainees in a single UK deanery were invited to participate in an online, voluntary, anonymous survey via SurveyMonkey.

Results

64 (72.7%) of the trainees responded. 39.1% were ST3/4, 29.7% were ST5/6, 20.3% were ST7/8 and 10.9% were out of training (maternity & research). Thirty-five (55.6%) worked in district general hospitals. Forty (68.9%) trainees felt that they had fewer opportunities to be primary surgeon. Forty-two (67.7%) trainees did not have access to laparoscopic simulation trainers. Fifty-two (88.1%) trainees had their courses and 2 (3.4%) had their FRCS part 2 exam postponed. 16 (27.1%) trainees reported they had been off-sick, with a median of 7 days off (range 3-35 days). Thirty-three (55.9%) trainees felt more stressed due to the pandemic and 35 (59.4%) had symptoms of burnout.

Conclusions

The COVID-19 pandemic has had an unprecedented impact on all aspects of higher surgical training. The most noticeable impact has been on the reduction in the confidence in laparoscopic and endoscopic skills.

Coronary arterial compression testing by simultaneous balloon valvuloplasty and coronary angiography in an English bulldog with pulmonary valve stenosis

A 4-year-old male neutered English bulldog presented for heart murmur evaluation. Echocardiography identified severe pulmonic stenosis (an echocardiography-derived transpulmonary pressure gradient of 100 mmHg), and computed tomography confirmed the presence of an anomalous coronary artery with a prepulmonic course of the left coronary artery arising from the right coronary ostium. Before artificial pulmonic valve implantation, a coronary compression test was performed. A simultaneous aortic root angiogram and pulmonic balloon valvuloplasty revealed complete occlusion of the circumflex branch. Artificial valve implantation was aborted with concern for fatal coronary compression after implantation. Coronary compression testing is a critical component of the evaluation before catheter-based implantation of conduits across the pulmonic valve.

Solitary Cardiac Low-Grade Neuroendocrine Tumor: A Case Report and Review of the Literature

Introduction/Objective

Primary tumors of the heart are uncommon; even rarer are primary cardiac neuroendocrine tumors. To our knowledge, only two cases have been described to date, both being high-grade tumors. We report a solitary low-grade neuroendocrine tumor of the heart, unexpectedly discovered on the wall of the right ventricle in a 44-year-old man during aortic valve repair for infectious bacterial endocarditis.

Results

Frozen section was sent intraoperatively and showed a plasmacytoid neoplasm. Final pathology of the biopsies showed a tumor composed of both cohesive and discohesive plasmacytoid cells separated by a vascular network and strands of fibrosis. Neither necrosis nor a mitotic rate greater than 2 mitoses per 2 mm2 were seen. The tumor showed strong reactivity for AE1/3, synaptophysin and CDX2 with focal reactivity for chromogranin-A and CD56, confirming the diagnosis of a low-grade neuroendocrine tumor. Both an esophagogastroduodenoscopy and colonoscopy were performed and showed no evidence of a primary gastrointestinal tumor. PET-CT DOTATATE performed after complete resection of the tumor showed no abnormal radiotracer uptake. The possibility of an intestinal neuroendocrine tumor undetected by DOTATATE PET-CT with a single known metastasis to the heart was considered. This too, on the basis of the literature, was considered exceedingly rare. Complete resection of this patient’s tumor was considered sufficient treatment; the patient was advised to follow up annually with medical oncology.

Conclusion

The presentation and management of a solitary cardiac low-grade neuroendocrine tumor has not previously been described in the literature.

Changes in tuberculosis epidemiology, United States, 1993-2017

BACKGROUND: After 20 years of steady decline, the pace of decline of tuberculosis (TB) incidence in the United States has slowed.METHODS: Trends in TB incidence rates and case counts since 1993 were assessed using national US surveillance data. Patient characteristics reported during 2014-2017 were compared with those for 2010-2013.RESULTS: TB rates and case counts slowed to an annual decline of respectively 2.2% (95%CI -3.4 to -1.0) and 1.5% (95%CI -2.7 to -0.3) since 2012, with decreases among US-born persons and no change among non-US-born persons. Overall, persons with TB diagnosed during 2014-2017 were older, more likely to have combined pulmonary and extra-pulmonary disease than extra-pulmonary disease alone, more likely to be of non-White race, and less likely to have human immunodeficiency virus infection, or cavitary pulmonary disease. During 2014-2017, non-US-born persons with TB were more likely to have diabetes mellitus, while the US-born were more likely to have smear-positive TB and use non-injecting drugs.CONCLUSION: Changes in epidemiologic trends are likely to affect TB incidence in the coming decades. The Centers for Disease Control and Prevention has called for increased attention to TB prevention through the detection and treatment of latent tuberculous infection.

Population-based rates of hernia surgery in Ghana

PURPOSE

To estimate the population-based annual rate of hernia surgery in Ghana, so as to better define the met and unmet need and to identify opportunities to decrease the unmet need.

METHODS

Data on operations performed from June 2014 to May 2015 were obtained from representative samples of 48 of 124 district (first-level) hospitals, 9 of 11 regional (referral) hospitals, and 3 of 5 tertiary hospitals, and scaled-up to nationwide estimates. Rates of hernia surgery were compared to previously published annual incidence of symptomatic hernia in Ghana (210/100,000 population) and to published annual rates of hernia surgery in high-income countries (120-275/100,000).

RESULTS

Estimated 17,418 [95% uncertainty interval (UI) 8154-26,683] hernia operations were performed nationally. The annual rate of hernia operations was 65 operations/100,000 population (95% UI 30.2-99.0). The rate was considerably less than the annual incidence of new symptomatic hernia or rates of hernia surgery in high-income countries. Hernia operations represented 7.5% of all operations. Most hernia operations (74%) were performed at district hospitals. Most district hospitals (54%) did not have fully trained surgeons, but nonetheless performed 38% of district-level hernia operations.

CONCLUSIONS

The rate of hernia operations fell short of estimated need. Most hernia repairs were performed at district hospitals, many without fully trained surgeons. Future global surgery benchmarking needs to address both overall surgical rates as well as rates for specific highly important operations. Countries can strengthen their planning for surgical care by defining their total, met, and unmet need for hernia surgery.

A systematic surveillance programme for infectious salmon anaemia virus supports its absence in the Pacific Northwest of the United States

In response to reported findings of infectious salmon anaemia virus (ISAV) in British Columbia (BC), Canada, in 2011, U.S. national, state and tribal fisheries managers and fish health specialists developed and implemented a collaborative ISAV surveillance plan for the Pacific Northwest region of the United States. Accordingly, over a 3-1/2-year period, 4,962 salmonids were sampled and successfully tested by real-time reverse-transcription PCR. The sample set included multiple tissues from free-ranging Pacific salmonids from coastal regions of Alaska and Washington and farmed Atlantic salmon (Salmo salar L.) from Washington, all representing fish exposed to marine environments. The survey design targeted physiologically compromised or moribund animals more vulnerable to infection as well as species considered susceptible to ISAV. Samples were handled with a documented chain of custody and testing protocols, and criteria for interpretation of test results were defined in advance. All 4,962 completed tests were negative for ISAV RNA. Results of this surveillance effort provide sound evidence to support the absence of ISAV in represented populations of free-ranging and marine-farmed salmonids on the northwest coast of the United States.

Molecular testing of adult Pacific salmon and trout (Oncorhynchus spp.) for several RNA viruses demonstrates widespread distribution of piscine orthoreovirus in Alaska and Washington

This research was initiated in conjunction with a systematic, multiagency surveillance effort in the United States (U.S.) in response to reported findings of infectious salmon anaemia virus (ISAV) RNA in British Columbia, Canada. In the systematic surveillance study reported in a companion paper, tissues from various salmonids taken from Washington and Alaska were surveyed for ISAV RNA using the U.S.-approved diagnostic method, and samples were released for use in this present study only after testing negative. Here, we tested a subset of these samples for ISAV RNA with three additional published molecular assays, as well as for RNA from salmonid alphavirus (SAV), piscine myocarditis virus (PMCV) and piscine orthoreovirus (PRV). All samples (n = 2,252; 121 stock cohorts) tested negative for RNA from ISAV, PMCV, and SAV. In contrast, there were 25 stock cohorts from Washington and Alaska that had one or more individuals test positive for PRV RNA; prevalence within stocks varied and ranged from 2% to 73%. The overall prevalence of PRV RNA-positive individuals across the study was 3.4% (77 of 2,252 fish tested). Findings of PRV RNA were most common in coho (Oncorhynchus kisutch Walbaum) and Chinook (O. tshawytscha Walbaum) salmon.

PLA2G6-associated neurodegeneration (PLAN): further expansion of the clinical, radiological and mutation spectrum associated with infantile and atypical childhood-onset disease

Phospholipase A2 associated neurodegeneration (PLAN) is a major phenotype of autosomal recessive Neurodegeneration with Brain Iron Accumulation (NBIA). We describe the clinical phenotypes, neuroimaging features and PLA2G6 mutations in 5 children, of whom 4 presented with infantile neuroaxonal dystrophy (INAD). One other patient was diagnosed with the onset of PLAN in childhood, and our report highlights the diagnostic challenges associated with this atypical PLAN subtype. In this series, the neuroradiological relevance of classical PLAN features as well as apparent claval hypertrophy' is explored. Novel PLA2G6 mutations were identified in all patients. PLAN should be considered not only in patients presenting with a classic INAD phenotype but also in older patients presenting later in childhood with non-specific progressive neurological features including social communication difficulties, gait disturbance, dyspraxia, neuropsychiatric symptoms and extrapyramidal motor features.

Nanostructuring of the conjugated polyelectrolyte poly[9,9-bis(4-sulfonylbutoxyphenyl)fluorene-2,7-diyl-2,2'-bithiophene] in liquid crystalline C12E4 in bulk water and aligned thin films

We report on the conjugated polyelectrolyte 12 mM poly[9,9-bis(4-sulfonylbutoxyphenyl) fluorene-2,7-diyl-2,2'-bithiophene] (PBS-PF2T) mixed in concentrated aqueous 680 mM tetraethylene glycol monododecyl ether (C12E4) in bulk and thin films. A blue-shift in the fluorescence spectrum demonstrates breakup of PBS-PF2T aggregates in bulk aqueous C12E4. Small-angle X-ray scattering data indicate that this mixture follows a very similar phase behaviour to binary mixtures of a pure surfactant with water, including a micellar phase below about 20 °C, a lamellar phase in between about 20 and 70 °C and a proposed coexistence of water and the liquid surfactant solution above 70 °C. Molecular dynamics simulations reproduce these transitions and suggest that PBS-PF2T is incorporated into the surfactant headgroup region, and is, on average, perpendicular to the alkyl chains. In wet thin films, grazing-incidence small-angle X-ray scattering shows that the phase window for the lamellar phase becomes much narrower, located at about 30-34 °C. Weakly ordered phases exist both below and above these temperatures. These phases are isotropic, but lamellae become aligned in a stacked manner on the surface whether approached from low or high temperatures. Dry films are disordered but can be reversibly ordered and disordered and aligned and misaligned by maintaining the temperature at 30-34 °C and switching relative outside humidity between 32% and 100%.

Global disease burden of conditions requiring emergency surgery

BACKGROUND

Surgical disease is inadequately addressed globally, and emergency conditions requiring surgery contribute substantially to the global disease burden.

METHODS

This was a review of studies that contributed to define the population-based health burden of emergency surgical conditions (excluding trauma and obstetrics) and the status of available capacity to address this burden. Further data were retrieved from the Global Burden of Disease Study 2010 and the University of Washington's Institute for Health Metrics and Evaluation online data.

RESULTS

In the index year of 2010, there were 896,000 deaths, 20 million years of life lost and 25 million disability-adjusted life-years from 11 emergency general surgical conditions reported individually in the Global Burden of Disease Study. The most common cause of death was complicated peptic ulcer disease, followed by aortic aneurysm, bowel obstruction, biliary disease, mesenteric ischaemia, peripheral vascular disease, abscess and soft tissue infections, and appendicitis. The mortality rate was higher in high-income countries (HICs) than in low- and middle-income countries (LMICs) (24.3 versus 10.6 deaths per 100,000 inhabitants respectively), primarily owing to a higher rate of vascular disease in HICs. However, because of the much larger population, 70 per cent of deaths occurred in LMICs. Deaths from vascular disease rose from 15 to 25 per cent of surgical emergency-related deaths in LMICs (from 1990 to 2010). Surgical capacity to address this burden is suboptimal in LMICs, with fewer than one operating theatre per 100,000 inhabitants in many LMICs, whereas some HICs have more than 14 per 100,000 inhabitants.

CONCLUSION

The global burden of surgical emergencies is described insufficiently. The bare estimates indicate a tremendous health burden. LMICs carry the majority of emergency conditions; in these countries the pattern of surgical disease is changing and capacity to deal with the problem is inadequate. The data presented in this study will be useful for both the surgical and public health communities to plan a more adequate response.

Doing supplements to improve performance in club cycling: a life-course analysis

Using qualitative life-course and pathway analysis, this article explores the beliefs that serious club cyclists have about performance improvement, and what they think are appropriate and inappropriate ways of achieving it. We interviewed 11 cyclists from suburban clubs in Melbourne, Australia, and invited them to discuss their approach to training, racing, and supplementation. We found that each of the 11 cyclists were not only committed to the sport, but also paid a keen interest in bike technology and training regimes. In addition, they believed that supplement use was integral to meeting the physical and mental demands of their sport, even at club level. They also understood that supplement use, like training regimes, followed a sequential pathway where the accumulation of capacity, know-know, and knowledge, allowed progression to the next level of performance. And, like similar studies of club cycling in Europe, this cohort of cyclists balked at using banned substances, but also believed that in order to effectively transition to the elite - that is, professional - level, some additional supplement and drug-use was essential.

Social media and organ donor registration: the Facebook effect

Despite countless media campaigns, organ donation rates in the United States have remained static while need has risen dramatically. New efforts to increase organ donation through public education are necessary to address the waiting list of over 100,000 patients. On May 1, 2012, the online social network, Facebook, altered its platform to allow members to specify "Organ Donor" as part of their profile. Upon such choice, members were offered a link to their state registry to complete an official designation, and their "friends" in the network were made aware of the new status as a donor. Educational links regarding donation were offered to those considering the new organ donor status. On the first day of the Facebook organ donor initiative, there were 13 054 new online registrations, representing a 21.1-fold increase over the baseline average of 616 registrations. This first-day effect ranged from 6.9× (Michigan) to 108.9× (Georgia). Registration rates remained elevated in the following 12 days. During the same time period, no increase was seen in registrations from the DMV. Novel applications of social media may prove effective in increasing organ donation rates and likewise might be utilized in other refractory public health problems in which communication and education are essential.

Duration of equine influenza virus shedding and infectivity in immunised horses after experimental infection with EIV A/eq2/Richmond/1/07

Equine influenza (EI) is a major respiratory disease of horses. Recent outbreaks of EI have demonstrated the ease with which EI virus (EIV) can be transmitted internationally. This study aimed to improve our understanding of EIV shedding after infection of vaccinated horses, which would inform possible changes to current quarantine requirements. Our objectives were to compare commonly used diagnostic tests and to evaluate the relative merits of nasal and nasopharyngeal swabs for detection of EIV in vaccinated and unvaccinated ponies following EIV infection and to use these data to inform optimal quarantine procedures for the safe international movement of horses. Five ponies vaccinated against EI were infected experimentally with A/eq/Richmond/1/07 (Florida clade 2), 11 weeks after V2. Nasal and nasopharyngeal swabs were taken daily for 14 days and every 2 days for another 2 weeks. The 5 vaccinates were introduced sequentially for 48h to 3 groups of 2 naïve sentinel ponies each on days 2, 4 and 6 post-challenge respectively. Clinical signs of disease and EIV shedding were monitored for 14 days after co-mingling. EIV was detected by 3 different methods of detection (EIV nucleoprotein ELISA, EIV nucleoprotein qRT-PCR and isolation/titration in embryonated hens' eggs). Directigen™ EZ Flu A+B tests were also performed on samples from the vaccinated ponies for 6 days after infection. Results show that nasopharyngeal swabs were superior to nasal swabs, with increased frequency and amount of virus detected. The average mean duration of shedding was 6-8 days in naïve animals. All 3 sentinel groups were infected successfully with EIV after commingling with vaccinates, indicating up to 6 days of transmission. EI protection induced by vaccination is a dynamic process, naturally fluctuating and dependent on the time since last immunisation, with periods of high immunity (peak of immunity shortly after boost immunisation) and periods of susceptibility to EIV infection. This result indicates that vaccinated horses may actively transmit EIV if the immunity gap (a usual period of susceptibility between V2 and V3) is not adequately closed by immunisation. In infected sentinels EIV was detectable up to 12 days after commingling. Results also suggest that tests such as qRT-PCR may be a suitable substitute for time spent in pre-export quarantine.

Sustained outcomes of a peer-taught family education program on mental illness

OBJECTIVE

This study examines 6-month follow-up data from participants in a randomized trial of a peer-driven 12-session family support and education program, called family-to-family (FTF) and offered by the US National Alliance on Mental Illness, to determine whether improvements in distress, family functioning, coping and empowerment were sustained.

METHOD

Individuals randomized to the FTF condition were assessed after program completion and then 3 months later on measures of distress, family functioning, coping, and empowerment. We used a multilevel regression model (sas proc mixed) to test for significant changes over time (baseline, 3 and 9 months).

RESULTS

All significant benefits that FTF participants gained between baseline and immediately post-FTF were sustained at 9 months including reduced anxiety, improved family problem-solving, increased positive coping, and increased knowledge. Greater class attendance was associated with larger increases in empowerment and reductions in depression and displeasure with ill relative.

CONCLUSION

Evidence suggests that benefits of the FTF program were sustained for at least 6 months without any additional boosters or supports. Peer-based programs may produce sustained benefits for individuals seeking help in addressing challenges and stresses related to having a family member with a mental illness.

SU-E-I-34: Air Kerma to Estimated Entrance Skin Dose Look-Up Tables: A Tool to Improve Dose Awareness in the Angiography Suite

PURPOSE

Although air kerma (AK) is displayed during a case, often it does not represent the entrance skin dose (ESD), which can be estimated. The purpose of this work is to develop and provide system-customized AK-to- ESD look-up tables (LUTs) for immediate reference so that physicians can better evaluate the likelihood of deterministic skin reactions to weigh the risk-versus-benefit of continuing high-dose procedures.

METHODS

Four correction factors are applied to estimate ESD from AK: inverse square correction from the interventional reference point to the average entrance table position, backscatter factor, mean energy absorption coefficient ratio, and measured table attenuation. Correction factors are room and service specific; therefore, room-specific AK-to-ESD LUTs are posted for easy reference. LUTs also list corresponding tissue reactions and their approximate time-of-onset. Protocols can be established for nurse or technology staff to provide verbal AK dose notifications during the case at crucial skin reaction dose thresholds (e.g. 2Gy indicating possible skin erythema and 5Gy indicating potentially prolonged recovery or permanent skin damage). Patient follow-up protocols can be established if the estimated ESD exceeds a set trigger level (e.g. 5Gy). Staff and physicians surveys evaluate usefulness and impact of dose awareness by system users.

RESULTS

Two surveys report feedback on LUTs from physicians and technologists with 14 years median experience (range: 3-24 years). Over three-quarters of all angiography system users identify the LUTs and verbal dose notifications as positively affecting the institution's 'Patient First' initiative and roughly one-half of the imaging system users indicate that the LUTs and site-specific dose trigger level improves the dose awareness of care providers.

CONCLUSIONS

Our efforts have focused on educating care providers about the differences between displayed AK and the estimated ESD. LUTs provide physicians and staff an immediate reference for estimated ESD and the associated deterministic skin effects at specific dose levels.

Is Src a viable target for treating solid tumours?

Src was the first proto-oncogene to be discovered. Since then the role of Src has been extensively studied in vitro. Src is a key regulator of multiple signal transduction pathways and plays a significant part in cellular transformation. Dysfunction of Src, through overexpression or increased activation, has profound effects on basic cellular functions. Elevated Src expression and/or activation is evident across a wide range of solid tumour types, highlighting its place in carcinogenesis and making it an attractive therapeutic target. In this review, we discuss in vitro and in vivo data examining the role of Src in the different cellular processes involved in oncogenesis and metastasis, covering the association of Src with increased cell proliferation and survival, decreased cellular adhesion, increased cell motility and invasiveness, accelerated/advanced angiogenesis and pathogenic bone activity. We also review evidence gathered from human tumour tissue and translational research studies that further substantiates the role of Src in oncogenesis. A summary of Src inhibitors currently being developed and trialled as therapeutic agents is provided to underline Src as a potential molecular target for solid tumour therapy. Further clinical data are needed to conclusively demonstrate that Src inhibitors have clinical utility in the treatment of solid tumors.

Effects of long-term ethanol administration in a rat total enteral nutrition model of alcoholic liver disease

Male Sprague-Dawley rats were chronically fed a high-unsaturated-fat diet for 130 days by using total enteral nutrition (TEN), or the same diet in which ethanol (EtOH) isocalorically replaced carbohydrate calories. Additional groups were supplemented with the antioxidant N-acetylcysteine (NAC) at 1.7 g·kg(-1)·day(-1). Relative to an ad libitum chow-fed group, the high-fat-fed controls had three- to fourfold greater expression of fatty acid transporter CD36 mRNA and developed mild steatosis but little other hepatic pathology. NAC treatment resulted in increased somatic growth relative to controls (4.0 ± 0.1 vs. 3.1 ± 0.1 g/day) and increased hepatic steatosis score (3.5 ± 0.6 vs. 2.7 ± 1.2), associated with suppression of the triglyceride hydrolyzing protein adiponutrin, but produced no elevation in serum alanine aminotransferase (ALT). Chronic EtOH treatment increased expression of fatty acid transport protein FATP-2 mRNA twofold, resulting in marked hepatic steatosis, oxidative stress, and a twofold elevation in serum ALT. However, no changes in tumor necrosis factor-α or transforming growth factor-β expression were observed. Fibrosis, as measured by Masson's trichrome and picrosirius red staining, and a twofold increase in expression of type I and type III collagen mRNA, was only observed after EtOH treatment. Long-term EtOH treatment increased hepatocyte proliferation but did not modify the hepatic mRNAs for hedgehog pathway ligands or target genes or genes regulating epithelial-to-mesenchymal transition. Although the effects of NAC on EtOH-induced fibrosis could not be fully evaluated, NAC had additive effects on hepatocyte proliferation and prevented EtOH-induced oxidative stress and necrosis, despite a failure to reverse hepatic steatosis.