Androgenic steroids induce pathologic scarring in a preclinical porcine model via dysfunctional extracellular matrix deposition

Hypertrophic scarring is a major source of morbidity. Sex hormones are not classically considered modulators of scarring. However, based on increased frequency of hypertrophic scarring in patients on testosterone, we hypothesized that androgenic steroids induce abnormal scarring and developed a preclinical porcine model to explore these effects. Mini-swine underwent castration, received no testosterone (noT) or biweekly testosterone therapy (+T), and underwent excisional wounding. To create a delayed wound healing model, a subset of wounds were re-excised at 2 weeks. Scars from postoperative day 42 (POD42) and delayed wounds (POD28) were harvested 6 weeks after initial wounding for analysis via histology, bulk RNA-seq, and mechanical testing. Histologic analysis of scars from +T animals showed increased mean fibrosis area (16 mm2noT, 28 mm2+T; p = .007) and thickness (0.246 mm2noT, 0.406 mm2+T; p < .001) compared to noT. XX+T and XY+T scars had greater tensile burst strength (p = .024 and p = .013, respectively) compared to noT swine. Color deconvolution analysis revealed greater deposition of type I and type III collagen as well as increased collagen type I:III ratio in +T scars. Dermatopathologist histology scoring showed that +T exposure was associated with worse overall scarring (p < .05). Gene ontology analysis found that testosterone exposure was associated with upregulation of cellular metabolism and immune response gene sets, while testosterone upregulated pathways related to keratinization and laminin formation on pathway analysis. In conclusion, we developed a preclinical porcine model to study the effects of the sex hormone testosterone on scarring. Testosterone induces increased scar tissue deposition and appears to increase physical strength of scars via supraphysiologic deposition of collagen and other ECM factors. The increased burst strength seen in both XX and XY animals suggests that hormone administration has a strong influence on scar mechanical properties independent of chromosomal sex. Anti-androgen topical therapies may be a promising future area of research.

Invasion of spontaneous germinal centers by naive B cells is rapid and persistent

In autoreactive germinal centers (GC) initiated by a single rogue B cell clone, wild-type B cells expand and give rise to clones that target other autoantigens, known as epitope spreading. The chronic, progressive nature of epitope spreading calls for early interventions to limit autoimmune pathologies, but the kinetics and molecular requirements for wild-type B cell invasion and participation in GC remain largely unknown. With parabiosis and adoptive transfer approaches in a murine model of systemic lupus erythematosus, we demonstrate that wild-type B cells join existing GCs rapidly, clonally expand, persist, and contribute to autoantibody production and diversification. The invasion of autoreactive GCs by wild-type B cells required TLR7, B cell receptor specificity, antigen presentation, and type I interferon signaling. The adoptive transfer model provides a tool for identifying early events in the breaking of B cell tolerance in autoimmunity.

DOCK8 is essential for neutrophil mediated clearance of cutaneous S. aureus infection

DOCK8 deficient patients are susceptible to skin infection with Staphylococcus aureus which is normally cleared by neutrophils. We examined the mechanism of this susceptibility in mice. Dock8-/- mice had delayed clearance of S. aureus from skin mechanically injured by tape stripping. The numbers and viability of neutrophils in infected but not in uninfected, tape stripped skin were significantly reduced in Dock8-/- mice compared to WT controls. This is despite comparable numbers of circulating neutrophils, and normal to elevated cutaneous expression of Il17a and IL-17A inducible neutrophil attracting chemokines Cxcl1, Cxcl2 and Cxcl3. DOCK8 deficient neutrophils were significantly more susceptible to cell death upon in vitro exposure to S. aureus and exhibited reduced phagocytosis of S. aureus bioparticles but had a normal respiratory burst. Impaired neutrophil survival in infected skin and defective neutrophil phagocytosis likely underlie the susceptibility to cutaneous S. aureus infection in DOCK8 deficiency.

Invasion of spontaneous germinal centers by naive B cells is rapid and persistent

In autoreactive germinal centers (GC) initiated by a single rogue B cell clone, wild-type B cells expand and give rise to clones that target other autoantigens, known as epitope spreading. The chronic, progressive nature of epitope spreading calls for early interventions, but the kinetics and molecular requirements for wild-type B cell invasion and participation in GC remain largely unknown. With parabiosis and adoptive transfer approaches in a murine model of systemic lupus erythematosus, we demonstrate that wild-type B cells join existing GCs rapidly, clonally expand, persist, and contribute to autoantibody production and diversification. The invasion of autoreactive GCs required TLR7, B cell receptor specificity, antigen presentation, and type I interferon signaling. The adoptive transfer model provides a novel tool for identifying early events in the breaking of B cell tolerance in autoimmunity.

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

BACKGROUND

80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality.

METHODS

This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494.

FINDINGS

Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70-8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39-8·80) and upper-middle-income countries (2·06, 1·11-3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26-11·59) and upper-middle-income countries (3·89, 2·08-7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications.

INTERPRETATION

Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications.

FUNDING

National Institute for Health Research Global Health Research Unit.

Diabetic Ketoacidosis in Adolescents and Children: A Prospective Study of Blood versus Urine Ketones in Monitoring Therapeutic Response

BACKGROUND

diabetic ketoacidosis (DKA) is a potentially lethal complication of diabetes mellitus (DM). There is no study in Indonesia that compares the much-preferred capillary beta hydroxybutirate (β-OHB) measurement to urine acetoacetate in monitoring therapeutic response of DKA in adolescents.

METHODS

a prospective study of 37 adolescents and children with DKA in Cipto Mangunkusumo Hospital was done between June 2006 and March 2011. The patients were followed until the time of DKA resolution. Hourly measurement of random blood glucose, capillary β-OHB concentration, and urine ketones were done, while blood gas analysis and electrolyte were measured every four hours.

RESULTS

median time to resolution was 21 (9-52) hours. Compared to urine ketones, capillary β-OHB concentration showed stronger correlation with pH (r= -0,52, p= 0,003 vs r= -0,49, p= 0,005) and bicarbonate level (r=-0,60, p=0.000 vs r= -0.48, p=0.007) during the median time of DKA resolution. All capillary β-OHB measurement yielded negative results at median time of DKA resolution, while urine ketones were still detected up to 9 hours after resolution.

CONCLUSION

blood ketone concentration showed better correlation with pH and bicarbonate level, as a tool to monitor therapeutic response in DKA in adolescent, compared to traditional urine ketones test in adolescents.