Broad-Spectrum Matrix Metalloproteinase Inhibition Curbs Inflammation and Liver Injury but Aggravates Experimental Liver Fibrosis in Mice

Background Liver fibrosis is characterized by excessive synthesis of extracellular matrix proteins, which prevails over their enzymatic degradation, primarily by matrix metalloproteinases (MMPs). The effect of pharmacological MMP inhibition on fibrogenesis, however, is largely unexplored. Inflammation is considered a prerequisite and important co-contributor to fibrosis and is, in part, mediated by tumor necrosis factor (TNF)-α-converting enzyme (TACE). We hypothesized that treatment with a broad-spectrum MMP and TACE-inhibitor (Marimastat) would ameliorate injury and inflammation, leading to decreased fibrogenesis during repeated hepatotoxin-induced liver injury.Methodology/Principal Findings Liver fibrosis was induced in mice by repeated carbon tetrachloride (CCl4) administration, during which the mice received either Marimastat or vehicle twice daily. A single dose of CCl4was administered to investigate acute liver injury in mice pretreated with Marimastat, mice deficient in Mmp9, or mice deficient in both TNF-α receptors. Liver injury was quantified by alanine aminotransferase (ALT) levels and confirmed by histology. Hepatic collagen was determined as hydroxyproline, and expression of fibrogenesis and fibrolysis-related transcripts was determined by quantitative reverse-transcription polymerase chain reaction. Marimastat-treated animals demonstrated significantly attenuated liver injury and inflammation but a 25% increase in collagen deposition. Transcripts related to fibrogenesis were significantly less upregulated compared to vehicle-treated animals, while MMP expression and activity analysis revealed efficient pharmacologic MMP-inhibition and decreased fibrolysis following Marimastat treatment. Marimastat pre-treatment significantly attenuated liver injury following acute CCl4-administration, whereas Mmp9 deficient animals demonstrated no protection. Mice deficient in both TNF-α receptors exhibited an 80% reduction of serum ALT, confirming the hepatoprotective effects of Marimastat via the TNF-signaling pathway.Conclusions/Significance Inhibition of MMP and TACE activity with Marimastat during chronic CCl4administration counterbalanced any beneficial anti-inflammatory effect, resulting in a positive balance of collagen deposition. Since effective inhibition of MMPs accelerates fibrosis progression, MMP inhibitors should be used with caution in patients with chronic liver diseases

Anatomical meniscus construct with zone specific biochemical composition and structural organization

A PCL/hydrogel construct that would mimic the structural organization, biochemistry and anatomy of meniscus was engineered. The compressive (380 +/- 40 kPa) and tensile modulus (18.2 +/- 0.9 MPa) of the PCL scaffolds were increased significantly when constructs were printed with a shifted design and circumferential strands mimicking the collagen organization in native tissue (p < 0.05). Presence of circumferentially aligned PCL strands also led to elongation and alignment of the human fibrochondrocytes. Gene expression of the cells in agarose (Ag), gelatin methacrylate (GelMA), and GelMA-Ag hydrogels was significantly higher than that of cells on the PCL scaffolds after a 21-day culture. GelMA exhibited the highest level of collagen type I (COL1A2) mRNA expression, while GelMA-Ag exhibited the highest level of aggrecan (AGO) expression (p < 0.001, compared to PCL). GelMA and GelMA-Ag exhibited a high level of collagen type II (COL2A1) expression (p < 0.05, compared to PCL). Anatomical scaffolds with circumferential PCL strands were impregnated with cell-loaded GelMA in the periphery and GelMA-Ag in the inner region. GelMA and GelMA-Ag hydrogels enhanced the production of COL 1 and COL 2 proteins after a 6-week culture (p < 0.05). COL 1 expression increased gradually towards the outer periphery, while COL 2 expression decreased. We were thus able to engineer an anatomical meniscus with a cartilage-like inner region and fibrocartilage-like outer region

A new scoring system to predict mortality in community-acquired pneumonia: CURB (S)-65

OBJECTIVE: The first decision to be made in the case of community-acquired pneumonia (CAP) is whether hospitalization of the patient is mandatory. In this study, we aimed to investigate whether the addition of oxygenation parameters to CURB-65 has diagnostic value in predicting mortality in CAP. PATIENTS AND METHODS: A total of 903 CAP patients were included in the study. Patients with a CURB-65 score of 0 and 1 were classified as Group 1 and patients with a CURB-65 score of 2 or more were classified as Group 2. The prediction of mortality through Pneumonia Severity Index (PSI), CURB-65 and CURBS-65/CURBP- 65 with the addition of SaO(2) and PaO2 values; hence the four different models, was compared among all patient groups. RESULTS: As a result, 3.3% of the cases in Group 1 and 12.7% of the cases in Group 2 died. In both CURB-65 groups, it was noted that the frequency of patients with SaO(2) <90% was significantly higher in the dead group than in the alive patient group (p= 0.009 and p= 0.001, respectively). In the univariate analysis, PaO2<60, and SaO(2)<90 were significantly associated with mortality. Model 2 (CURBS-65) and Model 3 (CURBP-65) were examined, SaO(2)< 90 (OR 2.08) was found to have an effect on death. In predicting mortality by the receiver operating characteristics (ROC) analysis, it was understood that the CURBS-65 score had a slightly higher area under the curve (AUC) value than CURB-65. CONCLUSIONS: As a result, it has been shown that the use of CURBS-65 scoring instead of CURB-65 clinical scoring may be more useful in predicting mortality

What should be the appropriate minimal duration for patient examination and evaluation in pulmonary outpatient clinics?

INTRODUCTION: Patient examinations performed in a limited time period may lead to impairment in patient and physician relationship, defective and erroneous diagnosis, inappropriate prescriptions, less common use of preventive medicine practices, poor patient satisfaction, and increased violent acts against health-care staff. OBJECTIVE: This study aimed to determine the appropriate minimal duration of patient examination in the pulmonary practice. METHODS: A total of 49 researchers from ten different study groups of the Turkish Thoracic Society participated in the study. The researchers were asked to examine patients in an almost ideal manner, without time constraint under available conditions. RESULTS: A total of 1680 patient examinations were reviewed. The mean duration of patient examination in ideal conditions was determined to be 20.4 +/- 9.6 min. Among all steps of patient examination, the longest time was spent for "taking medical history." The total time spent for patient examination was statistically significantly longer in the university hospitals than in the governmental hospitals and training and research hospitals (P < 0.001). Among different patient categories, the patients with a chronic disorder presenting for the first time and were referred from primary or secondary to tertiary care for further evaluation have required the longest time for patient examination. CONCLUSION: According to our study, the appropriate minimal duration for patient examination is 20 min. It has been observed that in university hospitals and in patients with chronic pulmonary diseases, this duration has been increased to above 25 min. The durations in clinical practice should be planned accordingly

3D

© 2021 Wiley Periodicals LLC.Fabrication of scaffolds using polymers and then cell seeding is a routine protocol of tissue engineering applications. Synthetic polymers have adequate mechanical properties to substitute for some bone tissue, but they are generally hydrophobic and have no specific cell recognition sites, which leads to poor cell affinity and adhesion. Some natural polymers, have high cell affinity but are mechanically weak and do not have the strength required as a bone supporting material. In the present study, 3D printed hybrid scaffolds were fabricated using PCL and GelMA carrying dental pulp stem cells (DPSCs), which is printed in the gaps between the PCL struts. This cell loaded GelMA was shown to support osteoinductivity, while the PCL provided mechanical strength needed to mimic the bone tissue. 3D printed PCL/GelMA and GelMA scaffolds were highly stable during 21 days of incubation in PBS. The compressive moduli of the hybrid scaffolds were in the range of the compressive moduli of trabecular bone. DPSCs were homogeneously distributed throughout the entire hydrogel component and exhibited high cell viability in both scaffolds during 21 days of incubation. Upon osteogenic differentiation DPSCs expressed two key matrix proteins, osteopontin and osteocalcin. Alizarin red staining showed mineralized nodules, which demonstrates osteogenic differentiation of DPSCs within GelMA. This construct yielded a very high cell viability, osteogenic differentiation and mineralization comparable to cell culture without compromising mechanical strength suitable for bone tissue engineering applications. Thus, 3D printed, cell loaded PCL/GelMA hybrid scaffolds have a great potential for use in bone tissue engineering applications