Etiology, Classification, Diagnostics, and Conservative Management of Osteochondral Lesions of the Talus. 2023 Recommendations of the Working Group "Clinical Tissue Regeneration" of the German Society of Orthopedics and Traumatology.

Methods: Peer-reviewed literature was analyzed regarding different topics relevant to osteochondral lesions of the talus (OLTs) treatment. This process concluded with a statement for each topic reflecting the best scientific evidence available for a particular diagnostic or therapeutic concept, including the grade of recommendation. Besides the scientific evidence, all group members rated the statements to identify possible gaps between literature and current clinical practice.

Empfehlungen der AG Klinische Geweberegeneration zur Behandlung von Knorpelschäden am Kniegelenk.

The Working Group of the German Orthopedic and Trauma Society (DGOU) on Tissue Regeneration has published recommendations on the indication of different surgical approaches for treatment of full-thickness cartilage defects in the knee joint in 2004, 2013 and 2016. Based upon new scientific knowledge and new developments, this recommendation is an update based upon the best clinical evidence available. In addition to prospective randomised controlled clinical trials, this also includes studies with a lower level of evidence.

[Relevance of meniscus loss for the progression of osteoarthritis and treatment options for early arthritis].

Meniscal tears are still one of the most frequent lesions in the knee joint. The relevance of meniscus loss for the development of osteoarthritis is undisputed. Meniscus repair, replacement and transplantation play an important role in the treatment of early arthritis, especially when they are a part of a master plan including alignment correction, stabilization and cartilage surgery, if needed.

Autologous chondrocyte implantation (ACI) for cartilage defects of the knee: A guideline by the working group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Trauma (DGOU).

Background: Autologous chondrocyte implantation (ACI) is an established and well-accepted procedure for the treatment of localised full-thickness cartilage defects of the knee.

Methods: The present review of the working group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Trauma (DGOU) describes the biology and function of healthy articular cartilage, the present state of knowledge concerning therapeutic consequences of primary cartilage lesions and the suitable indication for ACI.

Results: Based on best available scientific evidence, an indication for ACI is given for symptomatic cartilage defects starting from defect sizes of more than three to four square centimetres; in the case of young and active sports patients at 2.

Arylhydrocarbon receptor-dependent mIndy (Slc13a5) induction as possible contributor to benzo[a]pyrene-induced lipid accumulation in hepatocytes.

Non-alcoholic fatty liver disease is a growing problem in industrialized and developing countries. Hepatic lipid accumulation is the result of an imbalance between fatty acid uptake, fatty acid de novo synthesis, β-oxidation and secretion of triglyceride-rich lipoproteins from the hepatocyte. A central regulator of hepatic lipid metabolism is cytosolic citrate that can either be derived from the mitochondrium or be taken up from the blood via the plasma membrane sodium citrate transporter NaCT, the product of the mammalian INDY gene (SLC13A5).

Enhanced thyroid hormone breakdown in hepatocytes by mutual induction of the constitutive androstane receptor (CAR, NR1I3) and arylhydrocarbon receptor by benzo[a]pyrene and phenobarbital.

Xenobiotics may interfere with the hypothalamic-pituitary-thyroid endocrine axis by inducing enzymes that inactivate thyroid hormones and thereby reduce the metabolic rate. This induction results from an activation of xeno-sensing nuclear receptors. The current study shows that benzo[a]pyrene, a frequent contaminant of processed food and activator of the arylhydrocarbon receptor (AhR) activated the promoter and induced the transcription of the nuclear receptor constitutive androstane receptor (CAR, NR1I3) in rat hepatocytes.

[Autologous chondrocyte implantation (ACI) for cartilage defects of the knee: a guideline by the working group "Tissue Regeneration" of the German Society of Orthopaedic Surgery and Traumatology (DGOU)].

Autologous chondrocyte transplantation/implantation (ACT/ACI) is an established and recognised procedure for the treatment of localised full-thickness cartilage defects of the knee. The present review of the working group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Traumatology (DGOU) describes the biology and function of healthy articular cartilage, the present state of knowledge concerning potential consequences of primary cartilage lesions and the suitable indication for ACI. Based on current evidence, an indication for ACI is given for symptomatic cartilage defects starting from defect sizes of more than 3-4 cm2; in the case of young and active sports patients at 2.

Intracellular pH regulation in unstimulated Calliphora salivary glands is Na+ dependent and requires V-ATPase activity.

Salivary gland cells of the blowfly Calliphora vicina have a vacuolar-type H(+)-ATPase (V-ATPase) that lies in their apical membrane and energizes the secretion of a KCl-rich primary saliva upon stimulation with serotonin (5-hydroxytryptamine). Whether and to what extent V-ATPase contributes to intracellular pH (pH(i)) regulation in unstimulated gland cells is unknown. We used the fluorescent dye BCECF to study intracellular pH(i) regulation microfluorometrically and show that: (1) under resting conditions, the application of Na(+)-free physiological saline induces an intracellular alkalinization attributable to the inhibition of the activity of a Na(+)-dependent glutamate transporter; (2) the maintenance of resting pH(i) is Na(+), Cl(-), concanamycin A and DIDS sensitive; (3) recovery from an intracellular acid load is Na(+) sensitive and requires V-ATPase activity; (4) the Na(+)/H(+) antiporter is not involved in pH(i) recovery after a NH(4)Cl prepulse; and (5) at least one Na(+)-dependent transporter and the V-ATPase maintain recovery from an intracellular acid load.

Human mesenchymal stromal cells express CD14 cross-reactive epitopes.

Mesenchymal stromal cells (MSCs) do not express a unique definite epitope or marker gene. As such, minimal criteria were recently established for defining multipotent MSC. These criteria include expression of CD73, CD90, CD105, and a lack of hematopoietic marker expression.

Remodeling of articular cartilage and subchondral bone after bone grafting and matrix-associated autologous chondrocyte implantation for osteochondritis dissecans of the knee.

Background: Osteochondritis dissecans (OCD) of the knee is a challenging problem. Previously, the authors implemented a novel 1-step surgical procedure for OCD treatment consisting of matrix-associated autologous chondrocyte implantation (ACI) and simultaneous bone reconstruction including the subchondral lamina.

Purpose: This study presents the 2-to 5-year results after this technique, assessing correlations of clinical function and cartilage and bone remodeling processes.

Hypoxia reduces the inhibitory effect of IL-1beta on chondrogenic differentiation of FCS-free expanded MSC.

Objective: Mesenchymal stromal cells (MSC) are a promising tool for tissue engineering of the intervertebral disc (ID). The IDs are characterized by hypoxia and, after degeneration, by an inflammatory environment as well. We therefore investigated the effects of inflammation induced with interleukin (IL)-1beta and of hypoxia (2% O(2)) on the chondrogenic differentiation of MSC.

Isolation of functionally distinct mesenchymal stem cell subsets using antibodies against CD56, CD271, and mesenchymal stem cell antigen-1.

Background: Conventionally, mesenchymal stem cells are functionally isolated from primary tissue based on their capacity to adhere to a plastic surface. This isolation procedure is hampered by the unpredictable influence of co-cultured hematopoietic and/or other unrelated cells and/or by the elimination of a late adhering mesenchymal stem cells subset during removal of undesired cells. To circumvent these limitations, several antibodies have been developed to facilitate the prospective isolation of mesenchymal stem cells.

Articular cartilage defects in the knee--basics, therapies and results.

Full-thickness defects of the articular cartilage in the knee joint have lower regenerative properties than chondral lesions of the ankle. In order to avoid early osteoarthritis, symptomatic articular cartilage defects in younger patients should undergo biological reconstruction as soon as possible. Various surgical procedures are available to biologically resurface the articular joint line.

Intracellular pH homeostasis and serotonin-induced pH changes in Calliphora salivary glands: the contribution of V-ATPase and carbonic anhydrase.

Blowfly salivary gland cells have a vacuolar-type H(+)-ATPase (V-ATPase) in their apical membrane that energizes secretion of a KCl-rich saliva upon stimulation with serotonin (5-hydroxytryptamine, 5-HT). We have used BCECF to study microfluometrically whether V-ATPase and carbonic anhydrase (CA) are involved in intracellular pH (pH(i)) regulation, and we have localized CA activity by histochemistry. We show: (1) mean pH(i) in salivary gland cells is 7.

3-Dimensional ultrasound imaging for meniscal lesions.

Purpose: The aim of this prospective study was to evaluate preoperative three-dimensional ultrasound scans for the detection of meniscal lesions with a special focus on interobserver reliability.

Methods: Forty one patients with clinical signs of meniscal lesions were preoperatively examined by ultrasound using the 3-D technique (11.7 MHz linear transducer).

Chondrogenic potential of human adult mesenchymal stem cells is independent of age or osteoarthritis etiology.

Osteoarthritis (OA) is a multifactorial disease strongly correlated with history of joint trauma, joint dysplasia, and advanced age. Mesenchymal stem cells (MSCs) are promising cells for biological cartilage regeneration. Conflicting data have been published concerning the availability of MSCs from the iliac crest, depending on age and overall physical fitness.

[Treatment of osteochondritis dissecans of the knee: one-step procedure with bone grafting and matrix-supported autologous chondrocyte transplantation].

Aim: The aim of this study was to establish and assess a one-step reconstruction procedure of deep osteochondral defects of the knee joint with bone grafting and matrix-supported autologous chondrocyte transplantation in osteochondritis dissecans.

Method: Between 2004 and 200622 patients with osteochondral defects in the weight-bearing zone of the femoral condyles(ICRS OCD III and IV) were reconstructed simultaneously with bone grafting and matrix-supported autologous chondrocyte transplantation (NOVOCART 3D). All patients were analysed prospectively.

Novel markers for the prospective isolation of human MSC.

The isolation of mesenchymal stem cells (MSC) from primary tissue is hampered by the limited selectivity of available markers. So far, CD271 is one of the most specific markers for bone marrow (BM)-derived MSC. In search of additional markers, monoclonal antibodies (mAbs) with specificity for immature cells were screened by flow cytometry for their specific reactivity with the rare CD271(+) population.

Human placenta and bone marrow derived MSC cultured in serum-free, b-FGF-containing medium express cell surface frizzled-9 and SSEA-4 and give rise to multilineage differentiation.

Conventionally, mesenchymal stem cells (MSC) are generated by plating cells from bone marrow (BM) or other sources into culture flasks and selecting plastic-adherent cells with fibroblastoid morphology. These cells express CD9, CD10, CD13, CD73, CD105, CD166, and other markers but show only a weak or no expression of the embryonic markers stage-specific embryonic antigen-4 (SSEA-4), Oct-4 and nanog-3. Using a novel protocol we prepared MSC from BM and non-amniotic placenta (PL) by culture of Ficoll-selected cells in gelatin-coated flasks in the presence of a serum-free, basic fibroblast growth factor (b-FGF)-containing medium that was originally designed for the expansion of human embryonic stem cells (ESC).

[Cartilage repair in the knee joint].

Full thickness defects of the articular cartilage in the knee joint have lower regenerative properties compared to chondral lesions of the ankle. In order to avoid early osteoarthritis, symptomatic articular cartilage defects in younger patients should undergo biological reconstruction as early as possible. There are different surgical procedures available to achieve a biological resurfacing of the articular joint line.

[Value of three-dimensional ultrasound and MRI in meniscal lesions].

Background: The aim of this prospective study was the evaluation of preoperative three-dimensional ultrasound in detecting meniscal lesions compared to preoperative MRI.

Methods: A total of 34 patients with clinical signs of meniscal lesions were examined preoperatively (11.7 MHz linear transducer) using the 3-D technique.

cAMP regulates plasma membrane vacuolar-type H+-ATPase assembly and activity in blowfly salivary glands.

Reversible assembly of the V0V1 holoenzyme from V0 and V1 subcomplexes is a widely used mechanism for regulation of vacuolar-type H+-ATPases (V-ATPases) in animal cells. In the blowfly (Calliphora vicina) salivary gland, V-ATPase is located in the apical membrane of the secretory cells and energizes the secretion of a KCl-rich saliva in response to the hormone serotonin. We have examined whether the cAMP pathway, known to be activated by serotonin, controls V-ATPase assembly and activity.

Arthroscopic fixation of the subscapularis tendon in the reverse Hill-Sachs lesion for traumatic unidirectional posterior dislocation of the shoulder.

Posterior unidirectional instability of the shoulder following trauma is frequently associated with a cartilage-bone defect on the anterior joint surface of the humeral head. This defect can catch on the posterior joint surface during internal rotation of the arm, which causes redislocation of the humeral head in a posterior direction, thus increasing joint destruction. We describe a new arthroscopic surgical technique in which the subscapularis tendon is mobilized and attached to the defect using nonabsorbable or bioabsorbable suture anchors.