Momordica charantia (bitter melon) attenuates high-fat diet-associated oxidative stress and neuroinflammation

Purpose

Microglia and Müller cells are prominent participants in retinal responses to injury and disease that shape eventual tissue adaptation or damage. This investigation examined how microglia and Müller cells interact with each other following initial microglial activation.

Methods

Mouse Müller cells were cultured alone, or co-cultured with activated or unactivated retinal microglia, and their morphological, molecular, and functional responses were evaluated. Müller cell-feedback signaling to microglia was studied using Müller cell-conditioned media. Corroborative in vivo analyses of retinal microglia-Müller cell interactions in the mouse retina were also performed.

Results

Our results demonstrate that Müller cells exposed to activated microglia, relative to those cultured alone or with unactivated microglia, exhibit marked alterations in cell morphology and gene expression that differed from those seen in chronic gliosis. These Müller cells demonstrated in vitro (1) an upregulation of growth factors such as GDNF and LIF, and provide neuroprotection to photoreceptor cells, (2) increased pro-inflammatory factor production, which in turn increased microglial activation in a positive feedback loop, and (3) upregulated chemokine and adhesion protein expression, which allowed Müller cells to attract and adhere to microglia. In vivo activation of microglia by intravitreal injection of lipopolysaccharide (LPS) also induced increased Müller cell-microglia adhesion, indicating that activated microglia may translocate intraretinally in a radial direction using Müller cell processes as an adhesive scaffold.

Conclusion

Our findings demonstrate that activated microglia are able to influence Müller cells directly, and initiate a program of bidirectional microglia-Müller cell signaling that can mediate adaptive responses within the retina following injury. In the acute aftermath following initial microglia activation, Müller cell responses may serve to augment initial inflammatory responses across retinal lamina and to guide the intraretinal mobilization of migratory microglia using chemotactic cues and adhesive cell contacts. Understanding adaptive microglia-Müller cell interactions in injury responses can help discover therapeutic cellular targets for intervention in retinal disease.     

Functional and Patient Reported Outcomes Following Total Glans Resurfacing

BackgroundWhilst there is a trend away from aggressive nonorgan sparing surgical treatments for malignant penile disease, a variety of penile preservation options exist but functional outcomes and patient reported outcomes (PROs) in this area are poorly reported to date.AimThe aim of this study is to report functional outcomes and PROs of total glans resurfacing (TGR) in a consecutive series of patients with lichen sclerosis (LS) or localized penile cancer (PC).MethodsFrom 2004 to 2018 a consecutive series of patients underwent TGR for the management of LS or localized PC in a tertiary referral network. Patient clinical records and operative notes were retrospectively reviewed. Statistical analysis was conducted with Stata 12.OutcomesUrinary and sexual outcomes were recorded utilizing both the International Index of Erectile Function (IIEF) and International Prostate Symptom Score (IPSS) validated questionnaires while PROs were extrapolated from a 5-item “ad hoc” telephone questionnaire administered at 1 year post procedure.Results37 consecutive patients were enrolled. Histology results demonstrated LS in 16 patients, with the remaining 21 having a diagnosis of PC. The most common reasons for patient presentation were local pain (32.4%), pruritus (37.8%) and bleeding (29.7%). Median follow-up was 22 (IQR 13–77) months. Median age was 62 (IQR 55–68).Neither of the questionnaires assessing urinary and sexual function showed any significant deterioration after surgery. Glans sensitivity was fully maintained in 89.2% of cases. 94.5% of patients reported to be fully satisfied with the aesthetic appearance of the penis and would consider undergoing the same procedure again if necessary. 91.9% of patients would recommend the same procedure to someone else. An overall improvement of the quality of life was reported by 86.4% of patients.Clinical ImplicationsTGR should be considered a treatment of choice for selected cases of benign or malignant penile lesionsStrengths and LimitationsOur study has some limitations, the first being its retrospective nature. Furthermore, despite being one of the largest series to date, follow-up duration is somewhat limited and a control group is lacking.ConclusionTGR represents an excellent surgical option ensuring satisfactory voiding and sexual function, as well as cosmesis for selected cases of penile lesions.M. Preto, M. Falcone, G. Blecher, et al. Functional and Patient Reported Outcomes Following Total Glans Resurfacing. J Sex Med 2021;18:1099–1103.     

De novo design of β-helical polypeptides

Many proteins, including several growth factor receptors such as the IGF-1R and EGFR family, contain variants of the β-helix fold. Inspection of the irregular protein β-helices suggested that different families of regular β-helical polypeptides can be designed using a series of hinged vectors and the constraints imposed by the geometry of a peptide backbone. We have conceived β-helices with five and six β-strands per turn and designed, in detail, a series of regular β-helices with rhomboidal or triangular cross-sections. Each β-helix was modeled by threading C^α atoms to follow the vectorial β-helix and then creating the H-bonded polypeptide backbone and appropriate side-chain orientations. The conformational stability of these regular β-helices was assessed using molecular dynamics simulations. Several potential repeat amino acid sequences were identified for different geometries of β-helix. Regular β-helices offer new possibilities for the study of protein folding, the production of nanofibers, catalysts, inhibitors of growth factor receptors and drug carriers.     

Antigen presentation,autoantibody production,and therapeutic targets in autoimmune liver disease

The liver is an important immunological organ that controls systemic tolerance. The liver harbors professional and unconventional antigen-presenting cells that are crucial for tolerance induction and maintenance. Orchestrating the immune response in homeostasis depends on a healthy and well-toned immunological liver microenvironment, which is maintained by the crosstalk of liver-resident antigen-presenting cells and intrahepatic and liver-infiltrating leukocytes. In response to pathogens or autoantigens, tolerance is disrupted by unknown mechanisms. Intrahepatic parenchymal and nonparenchymal cells exhibit unique antigen-presenting properties. The presentation of microbial and endogenous lipid-, metabolite- and peptide-derived antigens from the gut via conventional and nonconventional mechanisms can educate intrahepatic immune cells and elicit effector responses or tolerance. Perturbation of this balance results in autoimmune liver diseases, such as autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis. Although the exact etiologies of these autoimmune liver diseases are unknown, it is thought that the disruption of tolerance towards self-antigens and microbial metabolites and lipids, as well as alterations in bile acid composition, may result in changes in effector cell activation and polarization and may reduce or impair protective anti-inflammatory regulatory T and B cell responses. Additionally, the canonical and noncanonical transmission of antigens and antigen:MHC complexes via trogocytosis or extracellular vesicles between different (non) immune cells in the liver may play a role in the induction of hepatic inflammation and tolerance. Here, we summarize emerging aspects of antigen presentation, autoantibody production, and the application of novel therapeutic approaches in the characterization and treatment of autoimmune liver diseases.     

Pharmacologic treatment of hyperthyroidism during lactation

QUESTION I have a patient who has hyperthyroidism due to Graves disease. She was taking methimazole but discontinued when she found out she was pregnant. She is currently close to delivery and might require antithyroid therapy in the postpartum period. Can methimazole cross into human milk, and is breastfeeding safe for her infant?ANSWER The exposure of infants to methimazole or propylthiouracil through breast milk is minimal and not clinically significant. Women with hyperthyroidism using methimazole or propylthiouracil should not be discouraged from breastfeeding, as the benefits of breastfeeding largely outweigh the theoretical minimal risks.     

Trends of medication errors in hospitalized children

Medication errors are a major cause of morbidity and mortality among hospitalized children. Due to the small volumes of stock solution involved, even a large error may look as an unsuspiciously small dose. Strategies were implemented to reduce medication errors in a large tertiary pediatric hospital in Toronto. Starting in 1993, several initiatives were taken, including a new hospital computer system for medication ordering, a review process to remove hazardous drugs from wards where they are not needed immediately, and in the training of pediatric residents. The rates of reported medication errors were compared before and after these initiatives were taken. Compared to baseline, there was a steady and a statistically significant decrease in medication errors through the decade. Total errors (actual and potential) decreased for nurses and physicians by half and for pharmacists by 75%. Actual incidents decreased by half. Moderate and severe errors decreased by more than 70%. It was concluded that a combination of several initiatives to decrease system and human errors has resulted in more than a 50% reduction of medication errors reaching the pediatric patient.