Leveraging the glymphatic and meningeal lymphatic systems as therapeutic strategies in Alzheimer's disease: an updated overview of nonpharmacological therapies.

Understanding and treating Alzheimer's disease (AD) has been a remarkable challenge for both scientists and physicians. Although the amyloid-beta and tau protein hypothesis have largely explained the key pathological features of the disease, the mechanisms by which such proteins accumulate and lead to disease progression are still unknown. Such lack of understanding disrupts the development of disease-modifying interventions, leaving a therapeutic gap that remains unsolved. Nonetheless, the recent discoveries of the glymphatic pathway and the meningeal lymphatic system as key components driving central solute clearance revealed another mechanism underlying AD pathogenesis. In this regard, this narrative review integrates the glymphatic and meningeal lymphatic systems as essential components involved in AD pathogenesis. Moreover, it discusses the emerging evidence suggesting that nutritional supplementation, non-invasive brain stimulation, and traditional Chinese medicine can improve the pathophysiology of the disease by increasing glymphatic and/or meningeal lymphatic function. Given that physical exercise is a well-regarded preventive and pro-cognitive intervention for dementia, we summarize the evidence suggesting the glymphatic system as a mediating mechanism of the physical exercise therapeutic effects in AD. Targeting these central solute clearance systems holds the promise of more effective treatment strategies.

Limitations and Possibilities of Transarterial Chemotherapeutic Treatment of Hepatocellular Carcinoma.

Because diagnostic tools for discriminating between hepatocellular carcinoma (HCC) and advanced cirrhosis are poor, HCC is often detected in a stage where transarterial chemoembolization (TACE) is the best treatment option, even though it provides a poor survival gain. Despite having been used worldwide for several decades, TACE still has many limitations. First, there is a vast heterogeneity in the cellular composition and metabolism of HCCs as well as in the patient population, which renders it difficult to identify patients who would benefit from TACE. Often the delivered drug does not penetrate sufficiently selectively and deeply into the tumour and the drug delivery system is not releasing the drug at an optimal clinical rate. In addition, therapeutic effectiveness is limited by the crosstalk between the tumour cells and components of the cirrhotic tumour microenvironment. To improve this widely used treatment of one of our most common and deadly cancers, we need to better understand the complex interactions between drug delivery, local pharmacology, tumour targeting mechanisms, liver pathophysiology, patient and tumour heterogeneity, and resistance mechanisms. This review provides a novel and important overview of clinical data and discusses the role of the tumour microenvironment and lymphatic system in the cirrhotic liver, its potential response to TACE, and current and possible novel DDSs for locoregional treatment.

Chylomicrons-Simulating Sustained Drug Release in Mesenteric Lymphatics for the Treatment of Crohn's-Like Colitis.

BACKGROUND AND AIMS: Alteration to both the structures and functions of mesenteric lymphatic vessels is a typical hallmark of Crohn's disease [CD]. Dysfunctional lymphatics was observed in patients with both CD and experimental colitis, suggesting mesenteric lymphatics could be potential therapeutic targets. This study aimed to develop a nano-delivery system which can enhance drug delivery in mesenteric lymphatic tissue [MLT] and evaluate the therapeutic effects in Crohn's colitis. METHODS: We designed a mesoporous silica nanoparticle [MSN] conjugated with long-chain fatty acid [LMSN] and covered with enteric coating [ELMSN] which can be specifically transported via the mesenteric lymphatic system. The therapeutic efficacy of laquinimod-loaded nanoparticles [LAQ@ELMSN] was evaluated in the well-established interleukin [IL]-10-/- spontaneous experimental colitis. RESULTS: ELMSNs induced sustainable drug release that markedly increased drug concentration in MLT. In experimental colitis, the lymphatics-targeting drug delivery system suppressed lymphangitis and promoted lymphatic drainage. The downregulation of pro-inflammatory cytokines and the downstream NF-κB-related proteins efficiently inhibited lymphangiogenesis and restored tight junctions of mesenteric lymphatic vessels [MLVs]. LAQ@ELMSN showed a superior therapeutic effect in ameliorating intestinal inflammation compared with free drug administration. Alteration of gut microbiota and metabolites in experimental colitis was also reversed by LAQ@ELMSN. CONCLUSION: Our study demonstrates a convenient, orally administered drug delivery system which enhances drug release in MLT. The results confirm the contribution of the mesenteric lymphatic system to the pathogenesis of gut inflammation and shed light on the application of lymphatics-targeting drug delivery therapy as a potential therapeutic strategy for CD treatment.

A Study Using Visual Art Methods to Explore the Perceptions and Barriers of Self-Management in Children and Adolescents with Lymphedema.

Background: The aims of this study were to explore, using visual art methodology, how children and adolescents perceive their lymphedema and conceptualize the barriers and enablers in self-management and to explore the role of an educational camp in promoting self-efficacy. Methods: Participants (speaking English, French, and Italian) were recruited during an educational camp for children with lymphedema. Children and adolescents used different methodologies to depict living and self-managing their condition. Younger children (aged 5-12 years) drew pictures, and all children and adolescents (aged 5-18 years) were given cameras and asked to take photographs that depicted their experience of learning self-management of their condition during the camp. Rose's critical visual methodology framework was used for analysis. Results: Analysis of the data produced five categories: Normal versus altered childhood, living with lymphedema; perceptions of lymphedema and self-care in younger children; adolescents' perception of living and managing lymphedema; learning self-efficacy; and insights into cultural differences in self-care. Conclusions: The study has shown that self-management is complex. Children and adolescents face many daily challenges and frustrations in managing their condition in addition to the normal challenges of development and growth that impact on: home life, time with friends, school activities, and relationships. Children expressed a deep longing for cure and a recognition that their lives were altered by having the condition that led to limitations in sport and wearing fashionable clothes and shoes. The importance of relationships with professionals was critical as was the experience of meeting and learning with other children through the camp experience. Attempts to simplify self-management techniques would appear to be a key priority as would a greater understanding of the self-beliefs young people have of their ability to influence and control their condition and its impact on their life.

A Study to Explore the Professional Conceptualization and Challenges of Self-Management in Children and Adolescents with Lymphedema.

Background: The aim of this study was to explore the professional experience of caring for children and adolescents with lymphedema and to explore the way in which they understand and implement self-management strategies and the influence of their own self-efficacy beliefs on this process. Methods and Results: Participants were recruited during an educational camp for children with lymphedema. Three individual semistructured focus groups were undertaken in English, French, and Italian with simultaneous translation. Data were analyzed using interpretative phenomenological analysis (IPA). Analysis of the data produced three superordinate themes: professional concepts of self-management, professional practice, and redefining the cornerstone of lymphedema care. An additional seven subthemes were as follows: readiness to self-management, professional perspectives on self-management, defining success and treatment failure, emotional burden, traditional views on complex decongestive therapy, new ways to practice, and sole practitioner versus multidisciplinary teams. Conclusions: The purpose of the study was to explore the challenges professionals face when introducing self-management to children and adolescents with lymphedema and their parents and to explore their own sense of self-efficacy in approaching this. The research allowed in-depth discussion about the ways they conceptualize self-management and faced professional challenges. The research highlighted the need to define what is considered an acceptable outcome within a complex and uncertain condition and the self-management strategies that are needed to support this.

A Study to Explore the Parental Impact and Challenges of Self-Management in Children and Adolescents Suffering with Lymphedema.

Background: Limited research has shown the impact lymphedema has on children and families. The aim of this study was to explore the parental experience of caring for a child or adolescent with lymphedema and the daily challenges of self-management and self-efficacy. Methods and Results: Participants were recruited during an educational camp for children with lymphedema (N = 26). Three individual semistructured focus groups were undertaken in English, French, and Italian with simultaneous translation. Data were analyzed using interpretative phenomenological analysis. Analysis identified four superordinate themes; the journey, treatment management, independence, and psychosocial impact. Ten subthemes were identified: bandaging/compression, professional support, holistic care, fear, self-efficacy, acceptance, friendship, guilt, distress, and hope. Conclusions: Parental self-management of children with lymphedema is complex and invades many aspects of life. Lack of professional agreement over what constitutes self-management leads to parental confusion and anxiety. Self-management is demanding, and parents are ambivalent to its effectiveness, but choose to persevere through fear of their child's condition deteriorating. Self-efficacy is evident in complex problem solving, despite parents believing that they are not adequately prepared for this.

Efeito do uso do taping na redução do volume do linfedema secundário ao câncer de mama: revisão da literatura / Effect of taping as treatment to reduce breast cancer lymphedema: literature review

O linfedema é a complicação mais frequente no pós-operatório de câncer de mama, podendo afetar diretamente as atividades diárias. O objetivo desse estudo foi verificar o uso do taping como forma alternativa/auxiliar de tratamento na redução do linfedema. Foi realizada uma revisão da literatura de artigos científicos indexados nas bases de dados PubMed, LILACS, MEDLINE, PEDro e Google Acadêmico, onde foram selecionados nove artigos científicos. Verificou-se que o uso do taping é uma técnica complementar na redução do linfedema, podendo ser uma forma alternativa de tratamento para a redução deste, apesar de não ser capaz de substituir a terapia compressiva multicamadas

Lymphedema is the most common complication during the postoperative period after surgery for breast cancer and can have a direct impact on daily activities. The objective of this study was to review the use of taping as an alternative/complementary treatment to reduce lymphedema. A literature review was conducted of scientific articles indexed on the PubMed, LILACS, MEDLINE, and PEDro databases and Google Scholar, and nine articles were selected. It was found that taping is a complementary therapy for reducing lymphedema, which may be used as an alternative treatment method, but cannot substitute multilayer compression therapy.

Targeting lymphatic function as a novel therapeutic intervention for rheumatoid arthritis.

Although clinical outcomes for patients with rheumatoid arthritis (RA) have greatly improved with the use of biologic and conventional DMARDs, approximately 40% of patients do not achieve primary clinical outcomes in randomized trials, and only a small proportion achieve lasting remission. Over the past decade, studies in murine models point to the critical role of the lymphatic system in the pathogenesis and therapy of inflammatory-erosive arthritis, presumably by the removal of catabolic factors, cytokines and inflammatory cells from the inflamed synovium. Murine studies demonstrate that lymphatic drainage increases at the onset of inflammatory-erosive arthritis but, as inflammation progresses to a more chronic phase, lymphatic clearance declines and both structural and cellular changes are observed in the draining lymph node. Specifically, chronic damage to the lymphatic vessel from persistent inflammation results in loss of lymphatic vessel contraction followed by lymph node collapse, reduced lymphatic drainage, and ultimately severe synovitis and joint erosion. Notably, clinical pilot studies in patients with RA report lymph node changes following treatment, and thus draining lymphatic vessels and nodes could represent a potential biomarker of arthritis activity and response to therapy. Most importantly, targeting lymphatics represents an innovative strategy for therapeutic intervention for RA.

Clinical Efficacy of Herbal Medicine for Pediatric Lymphatic Malformations: A Pilot Study.

BACKGROUND: Lymphatic malformations (LMs) are congenital malformations of the lymphatic system that commonly affect the head and neck region and cause marked cosmetic and functional complications. In this pilot study, we present eight children with LMs treated using an herbal medicine for this indication. METHODS: Between January 2009 and May 2014, eight children (four boys, four girls) with LMs were treated using oral administration of an herbal medicine, Eppikajyutsuto (TJ-28; Tsumura, Tokyo, Japan), as monotherapy. RESULTS: Four of the cases were macrocystic and four were mixed micro- and macrocystic. The mean treatment duration was 7.2 ± 2.9 months (range 5-12 mos). The mean LM volume shrinkage on magnetic resonance imaging was 54.5 ± 38.3% (macrocystic 73.6 ± 27.0%; mixed micro- and macrocystic 35.4 ± 41.5%). One of four macrocystic lesions had a marked reduction, two had a moderate reduction, and one had no response. A marked reduction was observed in three of the four mixed micro- and macrocystic cases; the other mixed cystic case had no response. The treatment was well tolerated, without severe adverse events. CONCLUSIONS: This preliminary study demonstrates the beneficial effects of TJ-28. Further evaluations of this therapeutic modality are warranted.

The effectiveness of intermittent pneumatic compression in long-term therapy of lymphedema of lower limbs.

BACKGROUND: The manual lymphatic drainage in lymphedema has proved to be successful; however, this method cannot be applied to millions of patients around the world. The only solution is to offer inexpensive, easily accessible mechanical devices for pneumatic compression (IPC). These devices should be designed on parameters of edema fluid hydromechanics. Recent data point to high pressures and long time of compression. AIM: To validate the effects of 3 years daily high pressure, long inflation time IPC therapy in terms of decrease of limb circumference/volume, tissue elasticity, histological changes, and incidental complications. METHODS: A group of 18 patients with unilateral leg lymphedema stage II to IV was treated for a period of 3 years using an 8-chamber sleeve, sequential inflation of chambers to 100-120 mmHg for 50 sec (total 400 sec). Limb circumference and tissue tonicity were measured at monthly intervals. Correlation between decrease in calf and thigh circumference and increase in elasticity was done. RESULTS: The treatment revealed durable permanent decrease of limb circumference and increased elasticity of tissues. The improvement was most expressed in the calf above the ankle and mid-calf. No complications as thigh ring or chronic genital edema were observed. There was no direct correlation between the decrease in limb circumference and increase in elasticity, most likely due to different mass of fibrous tissue. CONCLUSIONS: IPC takes over the permanently missing function of the obliterated lymphatics by squeezing edema tissue fluid to the regions with normal lymphatic drainage. The limb circumference is decreased or at least does not further increase, elasticity of tissue is increased and maintained. No complications in limb tissues were observed. The long-term, high pressure IPC, long inflation timed therapy can be safely be recommended to patients with lower limb lymphedema.

Obesity increases inflammation and impairs lymphatic function in a mouse model of lymphedema.

Although obesity is a major clinical risk factor for lymphedema, the mechanisms that regulate this effect remain unknown. Recent reports have demonstrated that obesity is associated with acquired lymphatic dysfunction. The purpose of this study was to determine how obesity-induced lymphatic dysfunction modulates the pathological effects of lymphatic injury in a mouse model. We used a diet-induced model of obesity in adult male C57BL/6J mice in which experimental animals were fed a high-fat diet and control animals were fed a normal chow diet for 8-10 wk. We then surgically ablated the superficial and deep lymphatics of the midportion of the tail. Six weeks postoperatively, we analyzed changes in lymphatic function, adipose deposition, inflammation, and fibrosis. We also compared responses to acute inflammatory stimuli in obese and lean mice. Compared with lean control mice, obese mice had baseline decreased lymphatic function. Lymphedema in obese mice further impaired lymphatic function and resulted in increased subcutaneous adipose deposition, increased CD45(+) and CD4(+) cell inflammation (P < 0.01), and increased fibrosis, but caused no change in the number of lymphatic vessels. Interestingly, obese mice had a significantly increased acute inflammatory reaction to croton oil application. In conclusion, obese mice have impaired lymphatic function at baseline that is amplified by lymphatic injury. This effect is associated with increased chronic inflammation, fibrosis, and adipose deposition. These findings suggest that obese patients are at higher risk for lymphedema due to impaired baseline lymphatic clearance and an increased propensity for inflammation in response to injury.

Effect of imiquimod as compared with surgery on the cancerization field in basal cell carcinoma.

BACKGROUND: Patients with basal cell carcinoma (BCC) have an increased risk of subsequent BCCs. It is possible that imiquimod might reduce this risk by acting on the cancerization field. OBJECTIVE: To examine the ability of imiquimod to reduce subsequent BCCs. METHODS: Retrospective cohort study of patients with BCC treated at our hospital between 2003 and 2011. The patients were divided into 2 groups depending on whether they had been treated with surgery or with imiquimod. Comparing the 2 groups, we analyzed the development of new BCCs, the time that elapsed between first and subsequent tumors, and the site of occurrence of the second BCC with respect to the first one (local, same lymphatic drainage basin or anatomic region, or other). Survival methods were used to analyze the data. RESULTS: We reviewed the charts of 623 patients. Of these, 550 had been treated with surgery (88.3%) and 71 with imiquimod (11.4%). Overall, a second BCC occurred in 36.4% of patients (n=227). The rate of occurrence was 38.2% in the surgery group and 23.9% in the imiquimod group (P=.02). The hazard ratio for the occurrence of a subsequent BCC was 2.13 (95% CI, 1.28-3.53) for patients treated with surgery compared with those treated with imiquimod. Imiquimod reduced the risk of a second BCC locally, regionally, and in the lymphatic drainage area. Our findings are limited by the retrospective nature of our study and the small number of patients treated with imiquimod. CONCLUSIONS: Imiquimod may reduce the risk of subsequent BCC in patients treated for BCC and its effect could last for up to 2 years in local, regional and lymphatic cancerization fields. We believe that the cancerization field concept should be expanded to include not only the local area, but also the pertinent anatomic region and the regional lymphatic drainage area.

Lymphatic diamine oxidase secretion stimulated by fat absorption is linked with histamine release.

Diamine oxidase (DAO) is abundantly expressed in mammalian small intestine catalyzing the oxidative breakdown of polyamines and histamine. The aim of this study was to determine the relationship between stimulation of intestinal diamine oxidase secretion with intestinal fat absorption and histamine release. Conscious intestinal lymph fistula rats were used. The mesenteric lymph ducts were cannulated and intraduodenal tubes were installed for the infusion of Liposyn II 20% (an intralipid emulsion). Lymphatic DAO activity and protein secretion were analyzed by radiometric assay and Western blot, respectively. Lymphatic histamine concentration was measured by ELISA. Infusion of Liposyn II (4.43 kcal/3 ml) resulted in a ~3.5-fold increase in lymphatic DAO protein secretion and DAO activity, peaking at 1 h and lasting for 3 h. Liposyn II infusion also increased the lymphatic histamine release, a substrate for DAO. To determine the relationship of DAO release with histamine release, histamine was administered intraperitoneally (10 mg/kg) in fasting rats and resulted in a significant doubling in lymphatic DAO activity, supporting a link between histamine and DAO. In addition, ip administration of the histamine H4 receptor antagonist JNJ7777120 significantly reduced the Liposyn II-induced DAO output by 65.9%, whereas H(1) (pyrilamine maleate), H(2) (ranitidine), and H(3) (thioperamide maleate) receptor antagonists had little effect. We conclude that DAO secretion may contribute to the catabolism of histamine released during fat absorption and this is probably mediated through the histamine H(4) receptor.

Lymphatic dysfunction impairs antigen-specific immunization, but augments tissue swelling following contact with allergens.

The lymph transports tissue-resident dendritic cells (DCs) to regional lymph nodes (LNs), having important roles in immune function. The biological effects on tissue inflammation following lymphatic flow obstruction in vivo, however, are not fully known. In this study, we investigated the role of the lymphatic system in contact hypersensitivity (CHS) responses using k-cyclin transgenic (kCYC(+/-)) mice, which demonstrate severe lymphatic dysfunction. kCYC(+/-) mice showed enhanced ear swelling to both DNFB and FITC, as well as stronger irritant responses to croton oil compared with wild-type littermates. Consistently, challenged ears of kCYC(+/-) mice exhibited massive infiltrates of inflammatory cells. In contrast, DC migration to regional LNs, drainage of cell-free antigen to LNs, antigen-specific IFN-γ production, and lymphocyte proliferation were impaired during the sensitization phase of CHS in kCYC(+/-) mice. Transfer experiments using lymphocytes from sensitized mice and real-time PCR analysis of cytokine expression using challenged ear revealed that ear swelling was enhanced because of impaired lymphatic flow. Collectively, we conclude that insufficient lymphatic drainage augments apparent inflammation to topically applied allergens and irritants. The findings add insight into the clinical problem of allergic and irritant contact dermatitis that commonly occurs in humans with peripheral edema of the lower legs.

Lymph duct ligation during ischemia/reperfusion prevents pulmonary dysfunction in a rat model with ω-3 polyunsaturated fatty acid and glutamine.

OBJECTIVE: The release of injurious factors into the mesenteric lymph from the ischemic intestine has been shown to contribute to lung injury and systemic inflammation after severe injury. We studied the effects of lung injury and systemic inflammatory reaction after intestinal ischemia/reperfusion and mesenteric lymph duct ligation with different nutritional statuses. METHODS: Rats (n = 72) were fed with a normal diet or received one of three diets (enteral nutrition, glutamine, or ω-3 polyunsaturated fatty acid) that were isocaloric and isonitrogenous. After 7 d, rats were subjected to 60 min of intestinal ischemia, ischemia plus mesenteric lymph duct ligation, or sham procedures. After 3 d of ischemia, the lymph nodes, lung, intestinal, liver, and blood were harvested and analyzed. RESULTS: In the different groups, lung injury, including levels of myeloperoxidase, nitric oxide, nitric oxide synthase, and the index of alveolar apoptosis, were partly prevented by mesenteric lymph duct ligation (P < 0.05). Likewise, the rats with ischemia/reperfusion, but not those with duct ligation plus ischemia/reperfusion, had a significant increase in intestinal permeability and decreased mucosal thickness. The serum cytokine and endotoxin concentrations were also lower in the lymph duct ligation groups, although there was no significant difference between lymph duct ligation and sham procedure. The lung and intestinal injuries were attenuated in the groups fed with glutamine and ω-3 polyunsaturated fatty acid. CONCLUSION: These results indicate that lymph duct ligation prevents lung injury, a systemic inflammation reaction, and gut-barrier dysfunction. Enteral glutamine and ω-3 polyunsaturated fatty acid modified the gut inflammation, prevented lung injury, and attenuated the systemic inflammation reaction.

[What do we know about the lymphatic drainage of the rectum?]. / Que savons-nous du drainage lymphatique du rectum ?

Lymph node (LN) involvement is one of the most significant prognostic factors of patients with rectal cancer. However, the distribution of rectal LN is not well known. The rectal LN are mainly located around the rectal arteries. In the mesorectum, the LN are mainly located posteriorly. The number of LN by patient varies considerably. Many reasons can explain this variability. Acquired factors such as infection, inflammation or metastatic involvement facilitate the detection of LN. In contrast, preoperative radiotherapy reduces the number and size of lymph nodes. The procedure of resection affects the number of LN harvested. Extensive lymphadenectomies increase the number of LN harvested. The technique used by pathologist has equally a major influence. The fat clearing method allows detection of a greater number of LN than manual dissection particularly for small LN. Toxicity of these solutions and a time-consuming process explain that fat clearing method is rarely used in clinical practice. Detection of rectal lymph nodes is difficult and tedious but is necessary for an accurate staging of patients with rectal cancer.

[A paclitaxel-resistant case of recurrent breast cancer responded to combination therapy of capecitabine and trastuzumab].

The patient was a 72-year-old female. Under the supervision of her former doctor, this patient had an operation and adjuvant chemotherapy for progressive breast cancer. During the following period, local recurrence of breast cancer and pulmonary lymphopathia developed. Although medication with paclitaxel was attempted, the focus was resistant to this treatment, and metastasis to the brain was also observed. Due to the dyscrasia above, the patient had difficulty breathing and became bedridden. Subsequently, combination treatment of capecitabine and trastuzumab was attempted. As a result,metastasis in the brain and pulmonary lymphopathia were improved. The patient recovered enough to be discharged at one time. However, his condition took a turn for the worse after the interruption of the combination treatment by a side effect. In conclusion, the combination treatment of capecitabine and trastuzumab is thought to be effective for non-responders to paclitaxel.

Experimental mycotoxicosis in chickens induced by ochratoxin A and penicillic acid and intervention with natural plant extracts.

The combined toxic effect of ochratoxin A (OTA) and penicillic acid (PA) on the body mass, the weight and pathomorphology of some internal organs was studied in 85 broiler chickens fed a mouldy diet containing 130, 300 or 800 ppb OTA and 1000-2000 ppb PA. The main pathomorphological changes were cloudy swelling and granular degeneration in the epithelium and mononuclear cell proliferation and activation of capillary endothelium in the kidney and liver; degenerative changes and depletion of lymphoid cells in lymphoid organs (bursa of Fabricius, thymus and spleen) were also seen. Protective effects of 5% total water extract of artichoke and a new natural phytosubstance Rosallsat against these pathomorphological changes were observed. A significant decrease in body mass and relative weight of lymphoid organs was found after 6 weeks of exposure and a greater decrease after 10 weeks of exposure to OTA and PA, and a protective effect of artichoke extract and a slight effect of Rosallsat against that decrease was observed. A significant increase in relative weight of liver and kidneys was also observed as well as a protective effect of artichoke extract against that increase. The quantity of OTA and the percentage of positive samples were significantly lower in tissues of chickens treated with artichoke extract or Rosallsat in addition to OTA than in those treated with only OTA.

[The theory of lymphangion and current approaches to the pathogenesis, diagnosis and treatment of lymphedema of the lower extremities]. / Teoriia limfangiona i sovremennye podkhody k patogenezu, diagnostike i lecheniiu limfedemy nizhnikh konechnostei.

The paper describes the results of examination carried out by the Sankt-Peterburg school of lymphologists, pertaining to the structure, physiological properties and function of lymphangions responsible for active lymph transport. The problems of the pathogenesis, diagnosis and treatment of lymphedema of the lower extremities used in clinical practice are reviewed from the standpoint of the new theory. The data obtained as a result of the clinico-morphofunctional studies allowed to delineate the stages of lymphedema as dependent on the degree of lymphocytic structure and function integrity. Based on the aforesaid the new approaches to the diagnosis and selection of the treatment methods for lymphedema of the lower extremities have been formulated.

Vascular endothelial growth factors C and D and their VEGFR-2 and 3 receptors in blood and lymphatic vessels in healthy and arthritic synovium.

OBJECTIVE: To localize vascular endothelial growth factor C (VEGF-C) and VEGF-D in synovial specimens in relation to their VEGFR-2 and VEGFR-3 receptors in blood and lymphatic vessels. METHODS: Immunohistochemical staining and messenger RNA analysis from control and arthritic synovial membrane specimens. RESULTS: Quantitative RT-PCR disclosed that VEGF-C mRNA copy numbers were higher than VEGF-D mRNA copy numbers in the rheumatoid arthritis (RA), osteoarthritis, and control patient groups studied (p < 0.01). Immunohistochemical staining localized VEGF-C to synovial lining cell layer, pericytes, and smooth muscle cells of blood vessels. The number of VEGF-C positive cells was increased in the synovial lining of ankylosing spondylitis (AS) and RA compared to control synovium. However, in contrast to control synovial lining, little if any VEGF-D was detected in AS or RA synovial lining. VEGFR-2 expressing stromal blood vessels, also positive for the vascular endothelial marker PAL-E and the basement membrane marker laminin, were more abundant in RA and AS than in controls. Interestingly, the lymphatic endothelial receptor VEGFR-3 was also expressed in most synovial vessels, especially in the sublining capillaries and venules. CONCLUSION: VEGF-C is strongly expressed in the hypertrophic synovial lining of arthritic joints, whereas VEGF-D expression is very low in AS and RA. The expression of VEGF-C and VEGF-D in pericytes and smooth muscle cells suggests that these factors may have a role in maintaining vascular homeostasis. The VEGF receptors VEGFR-2 and VEGFR-3 are present in most of the sublining blood vessels. The expression of the lymphatic marker VEGFR-3 in the sublining blood vessels may relate to fluid filtration and/or fenestrations. The relatively few lymphatic vessels along with increased vascular permeability in RA may contribute to the development of tissue edema and joint stiffness.