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Highlights • The anterior digastric jaw-opening muscle (AD) is crucial for vital oral functions. • Tooth loss and dental implant treatment can induce adaptive changes in the rat AD: • Increased variability of AD myofibre cross-sectional area. • Altered myosin heavy chain (MyHC) isoform myofibre-type composition. • Such changes may contribute to motor adaptation after dental treatment in humans. Abstract Objective: to determine if tooth loss and dental implant placement in rats induce changes in the morphological and histochemical features of the Anterior Digastric muscle. Design: Adult male Sprague-Dawley rats had their right maxillary molar teeth extracted. 'Extraction-1' and 'Extraction-2 groups were sacrificed, respectively, 4 or 8 weeks later, and an Implant group had an implant placement 2 weeks after the molar extraction, and rats were sacrificed 3 weeks later (n = 4/group). Naive rats (n = 3) had no treatment. Morphometric and immunohistochemical techniques quantified Anterior Digastric muscle myofibres' cross-sectional area (CSA) and myosin heavy chain (MyHC) isoform proportions. Significant ANOVAs were followed by post-hoc tests; p < 0.05 and 0.1 were considered to reflect levels of statistical significance. Results: In naïve rats, the peripheral regions of the Anterior Digastric muscle was dominated by MyHC-IIx/b isoform and there were no MyHC-I isoforms; the central regions dominated by MyHC-IIx/b and MyHC-IIa isoforms. Compared with naive rats, tooth extraction produced, 8 (but not 4) weeks later, a decreased proportion of fast-contracting fatigue-resistant MyHC-IIa isoform (p = 0.08), and increased proportion of fast and intermediate fatigue-resistance MyHC-IIa/x/b isoform (p = 0.03). Dental implant placement following tooth extraction attenuated the extraction effects but produced a decreased proportion of fast-contracting fatiguable MyHC-llx/b isoform (p = 0.03) in the peripheral region, and increased inter-animal variability in myofibre-CSAs. Conclusions: Given the crucial role that the Anterior Digastric muscle plays in many vital oral functions (e.g., chewing, swallowing), these changes may contribute to the changes in oral sensorimotor functions that occur in humans following such treatments. [ABSTRACT FROM AUTHOR]

Background & Aims Nonalcoholic fatty liver disease (NAFLD) is a strong risk factor for development of type 2 diabetes, but little is known about how long-term NAFLD or its histologic features affect risk. We aimed to investigate the cumulative incidence of type 2 diabetes in patients with NAFLD and to identify histologic factors that affect risk of diabetes. Methods We performed a retrospective study of 396 patients in Sweden diagnosed with NAFLD by biopsy analysis from 1971 through 2009 who did not have type 2 diabetes at baseline. Data on development of type 2 diabetes were collected from patient charts and national registers. Patients were categorized into groups with fibrosis stages 0–2 (n = 357) or stages 3–4 (n = 39). Hazard ratios of histologic parameters for type 2 diabetes development were calculated separately in a multivariate Cox regression model adjusted for sex, age, body mass index, and serum levels of triglycerides greater than 150 mg/dL. Results During a mean follow-up period of 18.4 years (range, 0–41 years), 132 individuals (33%) developed type 2 diabetes. A significantly higher proportion of patients with fibrosis stages 3–4 (51.2%) developed type 2 diabetes than patients with fibrosis stages 0–2 (31.3%) ( P = .02). For patients with fibrosis stages 0–2, fat score associated independently with development of type 2 diabetes (adjusted hazard ratio, 1.34; 95% confidence interval, 1.03–1.74; P = .03). No histologic factors associated with development of diabetes in patients with fibrosis stages 3–4. Presence of nonalcoholic steatohepatitis was not associated with development of type 2 diabetes. Conclusions In a retrospective study we found a higher proportion of patients with fibrosis stages 3–4 to develop type 2 diabetes than patients with fibrosis stages 0–2. In patients with fibrosis stages 0–2, fat score associates with risk of type 2 diabetes. [ABSTRACT FROM AUTHOR]

Background & Aims The increased prevalence of overweight has been suggested to contribute to the worldwide increase in liver diseases. We investigated if body mass index (BMI) in late adolescence predicts development of severe liver disease later in life. Methods We performed a cohort study using data from 44,248 men (18–20 years) conscribed to military service in Sweden between 1969 and 1970. Outcome data were collected from national registers to identify any diagnosis of severe liver disease (i.e., diagnosis of decompensated liver disease, cirrhosis or death in liver disease) until the end of 2009. A Cox regression model was applied using BMI as independent variable. The model was adjusted for use of alcohol, use of narcotics, smoking, high blood pressure and cognitive ability at time of conscription. Results During a follow-up period of a mean of 37.8 years, 393 men were diagnosed with severe liver disease (mean time to diagnosis 24.7 years). BMI (Hazard ratio [HR] = 1.05 for each unit increase in BMI, 95% confidence interval [CI]: 1.01–1.09, p = 0.008) and overweight (HR = 1.64 for BMI 25–30 compared to BMI 18.5–22.5, 95% CI: 1.16–2.32, p = 0.006) were associated with an increased risk of development of severe liver disease. Conclusions Being overweight in late adolescence is a significant predictor of severe liver disease later in life in men. Lay summary We investigated close to 45,000 Swedish men in their late teens enlisted for conscription in 1969–1970. After almost 40 years of follow-up, we found that being overweight was a risk factor for developing severe liver disease, independent of established risk factors such as alcohol consumption. [ABSTRACT FROM AUTHOR]

Background & Aims: Hereditary hemochromatosis (HH) is an autosomal-recessive disorder characterized by iron overload. Relatives of HH patients were screened and those with HH-associated mutations and an increased iron load were identified. However, little is known about their mortality or strategies for their management. We assessed mortality among Swedish patients with HH and their first-degree relatives using health and census registers. Methods: We performed a matched population-based cohort study of 3832 patients with HH and their 14,496 first-degree relatives using data collected from 1990 through 2007. Mortality data from these groups were compared with that of 38,969 population controls and their 143,349 first-degree relatives using Cox regression analyses. Results: Patients identified on the basis of hospitalization with HH had an increased risk (relative risk [RR]) for death (RR, 2.45; 95% confidence interval [CI], 2.27–2.64; 857 deaths). Patients identified through other means had a mortality risk that was lower than those identified in the hospital but higher than controls (RR, 1.15; 95% CI, 1.00–1.33; 216 deaths). Their first-degree relatives had only a marginally increased mortality risk (RR, 1.05; 95% CI, 1.01–1.10); this RR was similar to that of patients'' spouses (RR, 1.09; 95% CI, 0.86–1.38; 82 deaths). Patients with HH who also had a family history of HH did not have an increased mortality risk compared with other groups (RR, 1.05; 95% CI, 0.67–1.62; 21 deaths). Conclusions: Patients with HH have a modestly increased mortality risk compared with controls. The mortality of relatives is increased marginally compared with controls, and is similar among biological and nonbiological relatives. [Copyright &y& Elsevier]

The aim of the present study was to investigate whether histopathological changes can be detected in two soft palate muscles, the palatopharyngeus and the uvula, in 11 patients with long duration of sleep-disordered breathing (SDB). Muscle samples were collected from patients undergoing uvulo-palatopharyngoplasty (UPPP). Reference samples from the corresponding areas were obtained at autopsy from five previously healthy subjects. Muscle morphology, fibre type and myosin heavy chain (MyHC) compositions were analysed with enzyme-histochemical, immunohistochemical and biochemical techniques. The muscle samples from the patients, and especially those from the palatopharyngeus, showed several morphological abnormalities. The most striking findings were (i) increased amount of connective tissue, (ii) abnormal variability in fibre size, (iii) increased proportion of small-sized fibres, (iv) alterations in fibre type and MyHC compositions, (v) increased frequency of fibres containing developmental MyHC isoforms. Our findings point towards a pathological process of denervation and degeneration in the patient samples. Conclusively, the morphological abnormalities suggest a neuromuscular disorder of the soft palate in SDB patients. [Copyright &y& Elsevier]

Data on healthcare resource use and costs associated with nonalcoholic fatty liver disease (NAFLD) in clinical practice are lacking. We compared real-life healthcare costs of patients with NAFLD to matched controls. We performed a retrospective study of 646 patients with biopsy-proven NAFLD in Sweden from 1971 through 2009. Each patient was matched for age, sex, and county of residence with 10 persons from the general population (controls). We retrieved all healthcare contacts through Dec 31, 2014 from national registers. Unit costs were assigned to arrive at a total healthcare cost (in USD [$]) per study subject. During a mean follow-up of 19.9 years, we recorded a mean of 0.27 hospitalizations per year for patients with NAFLD vs 0.16 for controls (P <.001). This corresponded to an incremental cost of $635 per year for patients with NAFLD. Patients with NAFLD had a higher mean use of outpatient care visits: 1.46 contacts per year compared with 0.86 per year in controls, corresponding to $255 in additional costs (P <.001). Total costs incurred by patients with stage 3–4 fibrosis were higher than by patients with fibrosis stage 0–2 (mean annual costs, $4397 vs $629). Cumulative costs were higher for all stages of fibrosis compared to controls. Healthcare costs are nearly twice as high in patients with NAFLD than in matched controls. This is mostly attributable to higher costs for hospitalizations, but also to more outpatient visits. Patients with advanced fibrosis had the highest costs. [ABSTRACT FROM AUTHOR]

Several non-invasive scoring systems have been developed to determine risk of advanced fibrosis in non-alcoholic fatty liver disease (NAFLD). We examined the association between 4 scoring systems and incident severe liver disease and overall mortality in a large cohort of patients with biopsy-proven NAFLD. We performed a retrospective analysis of data from 646 patients with biopsy-proven NAFLD, recruited from 2 hospitals in Sweden, from 1971 through 2009. The NAFLD fibrosis score (NFS), FIB-4, APRI, and BARD scores were calculated at the time of the liver biopsy. Based on each score, patients were assigned to categories of low, intermediate, or high risk for advanced fibrosis. Overall mortality and severe liver disease (cirrhosis, decompensated liver disease, liver failure, or hepatocellular carcinoma) were ascertained through linkage with national registers until the end of 2014. Cox regression, area under the receiver operating characteristic (AUROC) curve, and C-statistic analyses were used to study the predictive capacity of each scoring system. During a mean follow-up time of 19.9±8.7 years, there were 214 deaths and 76 cases of severe liver disease. For overall mortality, AUROC curve values were: NFS, 0.72 (95% CI, 0.68–0.76); FIB-4, 0.72 (95% CI, 0.68–0.76); BARD, 0.62 (95% CI, 0.58–0.66); and APRI, 0.52 (95% CI, 0.47–0.57). For severe liver disease, AUROC curve values were: NFS, 0.72 (95% CI, 0.66–0.78); FIB-4, 0.72 (95% CI, 0.66–0.79); BARD, 0.62 (95% CI, 0.55–0.69); APRI, 0.69 (95% CI, 0.63–0.76). C-statistics for all scores were of moderate capacity to predict outcomes. In a retrospective analysis of data from 646 patients with biopsy-proven NAFLD, we found the NFS and the FIB-4 scores to most accurately determine risk of overall death or severe liver disease. However, the AUROC values for these scoring systems are not high enough for use in the clinic; new systems are needed to determine prognoses of patients with NAFLD. [ABSTRACT FROM AUTHOR]

Liver transplantation (LTX) has been described as a rescue treatment option in severe, intractable post-hepatectomy liver failure (PHLF), but is not considered to be indicated for this condition by many hepatobiliary and transplant surgeons. In this article we describe the clinical experience of five northern European tertiary centers in using LTX to treat selected patients with severe PHLF. All patients subjected to LTX due to PHLF at the participating centers were identified from prospective clinical databases. Preoperative variables, surgical outcome (both resection surgery and LTX) and follow-up data were assessed. A total of 10 patients treated with LTX due to severe PHLF from September 2008 to May 2020 were identified and included in the study. All patients but one were male and the median age was 70 years (range 49–72). In all patients the indication for liver resection was suspected malignancy, but in six patients post-resection pathology revealed benign or pre-malignant disease. There was no 90-day mortality after LTX. Patients were followed for a median of 49 months (13–153) and eight patients were alive without recurrence at last follow-up. In selected patients with PHLF LTX can be a life-saving procedure with low short-term risk. [ABSTRACT FROM AUTHOR]

The building blocks of DNA, dNTPs, can be produced de novo or can be salvaged from deoxyribonucleosides. However, to what extent the absence of de novo dNTP production can be compensated for by the salvage pathway is unknown. Here, we eliminated de novo dNTP synthesis in the mouse heart and skeletal muscle by inactivating ribonucleotide reductase (RNR), a key enzyme for the de novo production of dNTPs, at embryonic day 13. All other tissues had normal de novo dNTP synthesis and theoretically could supply heart and skeletal muscle with deoxyribonucleosides needed for dNTP production by salvage. We observed that the dNTP and NTP pools in WT postnatal hearts are unexpectedly asymmetric, with unusually high dGTP and GTP levels compared with those in whole mouse embryos or murine cell cultures. We found that RNR inactivation in heart led to strongly decreased dGTP and increased dCTP, dTTP, and dATP pools; aberrant DNA replication; defective expression of muscle-specific proteins; progressive heart abnormalities; disturbance of the cardiac conduction system; and lethality between the second and fourth weeks after birth. We conclude that dNTP salvage cannot substitute for de novo dNTP synthesis in the heart and that cardiomyocytes and myocytes initiate DNA replication despite an inadequate dNTP supply. We discuss the possible reasons for the observed asymmetry in dNTP and NTP pools in WT hearts. [ABSTRACT FROM AUTHOR]

Background & Aims Non-alcoholic fatty liver disease (NAFLD) is very common in the general population, but identifying patients with increased risk of mortality and liver-specific morbidity remains a challenge. Non-alcoholic steatohepatitis (NASH) is thought to enhance this risk; therefore, resolution of NASH is a major endpoint in current pharmacologic studies. Herein, we aim to investigate the long-term prognosis of a large cohort of NAFLD patients, and to study the specific effect of NASH and fibrosis stage on prognosis. Methods We conducted a retrospective cohort study of 646 biopsy-proven NAFLD patients. Each case was matched for age, sex and municipality to ten controls. Outcomes on mortality and severe liver disease, defined as cirrhosis, liver decompensation/failure or hepatocellular carcinoma, were evaluated using population-based registers. Cox regression models adjusted for age, sex and type 2 diabetes were used to examine the long-term risk according to fibrosis stage. Likelihood ratio tests were used to assess whether adding NASH to these models increased the predictive capacity. Laplace regression was used to estimate the time to severe liver disease according to stage of fibrosis. Results During a follow-up of mean 20 years (range 0–40) equivalent to 139,163 person-years, 12% of NAFLD patients and 2.2% of controls developed severe liver disease ( p <0.001). Compared to controls, the risk of severe liver disease increased per stage of fibrosis (hazard ratio ranging from 1.9 in F0 to 104.9 in F4). Accounting for the presence of NASH did not change these estimates significantly (likelihood ratio test >0.05 for all stages of fibrosis). Similar results were seen for overall mortality. The lower end of the 95% confidence interval for the 10 th percentile of time to development of severe liver disease was 22–26 years in F0-1, 9.3 years in F2, 2.3 years in F3, and 0.9 years to liver decompensation in F4. Conclusions In this, the largest ever study of biopsy-proven NAFLD, the presence of NASH did not increase the risk of liver-specific morbidity or overall mortality. Knowledge of time to development of severe liver disease according to fibrosis stage can be used in individual patient counselling and for public health decisions. Lay summary Non-alcoholic fatty liver disease (NAFLD) is very common in the general population, but reaching an accurate prognosis remains challenging. We investigate the long-term prognosis of a large cohort of NAFLD patients. In this, the largest ever study of biopsy-proven NAFLD, the presence of NASH did not increase the risk of liver-specific morbidity or overall mortality. Knowledge of time to development of severe liver disease according to fibrosis stage can be used in individual patient counselling and for public health decisions. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To clarify the morphological basis of the limited coronary reserve in hypertrophic cardiomyopathy (HCM). Background: Some of the symptoms in Hypertrophic cardiomyopathy (HCM), such as chest pain, dyspnea and arrhythmia, may be explained by myocardial ischemia. Many patients with HCM are known to exhibit these symptoms in the absence of atherosclerosis in the major coronary vessels. Decreased myocardial perfusion has been demonstrated in HCM, however, little is known about the myocardial capillary morphology in this disease. Methods: Using immunohistochemistry and morphometry, we analysed capillaries and cardiomyocytes in myectomy specimens from 5 patients with HCM with moderate hypertrophy and left ventricular outflow tract obstruction and in 5 control hearts. Results: The number of capillaries per cardiomyocyte (p <0.009) and number of capillaries per cardiomyocyte area unit, reflecting cardiomyocyte mass (p =0.009), were lower in individuals with HCM, i.e. indicating loss of capillaries. In HCM, the capillary density was 33% lower (p <0.05). Conclusions: Our morphologic findings show that the capillary supply, and thus the coronary reserve, is impaired in HCM with moderate hypertrophy and left ventricular outflow tract obstruction. These data may partly explain the limitation of myocardial perfusion in HCM, which is associated with worse prognosis. Furthermore, we present evidence of actual loss of myocardial capillaries in HCM and a defective capillary growth. [Copyright &y& Elsevier]