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1.
J Vasc Surg Cases Innov Tech ; 9(2): 101125, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37427036

RESUMO

Objective: The aim of the present study was to evaluate the safety, feasibility, and early efficacy of saphenous vein ablation using a water-specific 1940-nm diode laser wavelength using low linear endovenous energy density. Methods: We retrospectively analyzed a series of patients who had undergone endovenous laser ablation (EVLA) between July 2020 and October 2021 from the multicenter, prospectively maintained VEINOVA (vein occlusion with various techniques) registry. EVLA was performed using a water-specific 1940-nm radial laser fiber. In the same session, all insufficient tributaries were treated by phlebectomy or sclerotherapy. Tumescent anesthesia was injected into the perivenous space. The vein diameter, energy delivered, and linear endovenous density were reviewed at baseline. The incidence of venous thromboembolism, endovenous heat-induced thrombosis (EHIT), burns, phlebitis, paresthesia, and occlusion were reviewed at 2 days and 6 weeks of follow-up. We used descriptive statistics to describe the results. Results: Overall, 229 patients were identified. Of the 229 patients, 34 were excluded because of treatment of recurrent varicose veins at a previously operated site (residual or neovascularization). Finally, 108 patients with varicose veins and 87 with recurrent varicose veins (new varicose veins in an untreated area) due to disease progression were included in the present analysis. A total of 256 native saphenous veins (163 great saphenous veins, 53 small saphenous veins, and 40 accessory saphenous veins) in 224 legs had undergone EVLA. The mean patient age was 58.3 ± 16.5 years. Of the 195 patients, 134 (68.7%) were women and 61 (31.3%) were men. Nearly one half of the patients had a history of saphenous vein surgery (44.6%). The CEAP (clinical, etiology, anatomy, pathophysiology) class was C2 in 31 legs (13.8%), C3 in 108 (48.2%), C4a to C4c in 72 (32.1%), and C5 or C6 in 13 legs (5.8%). The treatment length was 34.8 ± 18.3 cm. The mean diameter was 5.0 ± 1.2 mm. The average linear endovenous density was 34.8 ± 9.2 J/cm. Concomitant miniphlebectomy was performed in 163 patients (83.6%) and concomitant sclerotherapy in 35 patients (18%). At 2 days and 6 weeks of follow-up, the occlusion rate of the treated truncal veins was 99.6% and 99.6%, respectively, with only one truncal vein (0.4%) with partial recanalization at 2 days and 6 weeks of follow-up. No cases of proximal deep vein thrombosis, pulmonary embolism, or EHIT had occurred at follow-up. Only one patient (0.5%) had developed calf deep vein thrombosis at 6 weeks of follow-up. The incidence of postoperative ecchymosis was rare (1.5%) and had resolved at 6 weeks of follow-up. Conclusions: EVLA of incompetent saphenous veins using the water-specific 1940-nm diode laser wavelength is feasible and appears to be safe and efficient with a high occlusion rate, minimal side effects, and a zero rate of EHIT.

2.
J Sex Med ; 18(2): 315-326, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33454205

RESUMO

BACKGROUND: Arteriogenic erectile dysfunction is a common disease oftentimes not satisfactory treatable with medical therapy. AIM: To assess the safety and clinical success rate of endovascular revascularization of erection-related arteries with the angiolite BTK stent in patients with arteriogenic erectile dysfunction. METHODS: A total of 100 consecutive men (61.8 ± 10 years) with atherosclerotic lesions in erection-related arteries agreed to participate and were included into a single-center all-comers registry. Endovascular therapy with angiolite BTK drug-eluting stents was performed on a total of 211 lesions. Patients received a baseline International Index of Erectile Function (IIEF)-15 questionnaire at first presentation and 3 and 12 months after stenting. An improvement by 4 points in the erectile function domain consisting of 6 questions (IIEF-6) was defined as minimal clinically important difference. A total of 24 patients with 52 stented arterial lesions underwent angiographic follow-up of the initially treated arterial side during secondary revascularization of the contralateral side (angiographic sub-study). OUTCOME: Clinical improvement of erections in 100 patients undergoing endovascular revascularization of erection-related arteries. RESULTS: No major adverse events occurred during endovascular revascularization or within 30 days thereafter. Technical success was achieved in all lesions and procedural success in all patients. At 1 year, 55 of 97 patients (56.7%) improved by at least 4 points in IIEF-6 score and thus achieved a clinically relevant improvement of erectile function.In the angiographic sub-study, arterial patency and binary restenosis were observed in 46 of 52 (88.5%) and in 8 of 52 (15.4%), respectively, after a mean follow-up of 9.6 ± 5.8 months. CLINICAL IMPLICATIONS: In patients with arteriogenic erectile dysfunction, endovascular therapy with a novel thin-strut sirolimus eluting stent is a safe and feasible treatment option. STRENGTHS & LIMITATIONS: This real-world arterial revascularization registry included patients with a multitude of risk factors for ED, thereby representing the heterogeneity in patients in the clinical practice, which is one of its strengths but also one of its weaknesses. Another strength was the focus being laid on analyzing outcomes of patients with arteriogenic ED using only a single endovascular device. Further studies are warranted to better define subgroups of patients with impaired clinical outcomes. CONCLUSION: Within the present all-comers registry, endovascular therapy of erectile dysfunction with the angiolite BTK stent was shown to be a safe and feasible treatment option resulting in clinical improvement rates comparable to earlier clinical trials although also showing that further research is warranted to define patient subgroups with particular benefits of endovascular therapy. Schönhofen J, Räber L, Knöchel J, et al. Endovascular Therapy for Arteriogenic Erectile Dysfunction With a Novel Sirolimus-Eluting Stent. J Sex Med 2021;18:315-326.


Assuntos
Stents Farmacológicos , Procedimentos Endovasculares , Disfunção Erétil , Stents Farmacológicos/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Disfunção Erétil/terapia , Humanos , Masculino , Sirolimo/efeitos adversos , Stents , Resultado do Tratamento
3.
J Vasc Surg Venous Lymphat Disord ; 9(4): 916-924, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33263288

RESUMO

OBJECTIVE: The use of endovenous thermal ablation (ETA) for the treatment of truncal varicose veins has been increasing worldwide; however, uncertainty remains regarding the need for thromboprophylaxis and follow-up of patients undergoing this minimally invasive procedure. A nationwide survey of among physicians performing ETA was conducted to assess the thromboprophylaxis practice and follow-up protocols after ETA in Switzerland. METHODS: A questionnaire was sent to all ETA-certified physicians (n = 193) in Switzerland. The survey covered procedure type, thromboprophylaxis (including pharmacologic and compression therapy), duplex ultrasound follow-up examinations, and the management of endovenous heat-induced thrombosis (EHIT). RESULTS: Overall, 121 responses were received, for a response rate of 62.7%. Of the 121 respondents, 71 were vascular medicine specialists (58.7%) and 46 were general or vascular surgeons (38.0%), representing the two largest groups of specialists, followed by 2 dermatologists (1.7%) and 2 interventional radiologists (1.7%). Pharmacologic thromboprophylaxis after ETA was always used by 86 physicians (71.1%), nearly always by 8 (6.6%), frequently used by 5 (4.1%), rarely used by 21 (17.4%), and never by 1 physician (0.8%). A direct oral anticoagulant drug was the preferred type of thromboprophylaxis used by 92 physicians (77.3%). The first dose of thromboprophylaxis was mostly administered immediately after intervention by 53 physicians (53.7%). The duration of postablation thromboprophylaxis ranged from 1 to 21 days, with 7 to 10 days used by 57 physicians. Compression therapy was used by all physicians, with large variation in duration ranging from 1 to 42 days after a single ETA session and after ETA with concomitant phlebectomy. Postablation duplex ultrasonography was performed routinely by 120 respondents (99.2%), and 84 respondents (69.4%) performed two to three duplex ultrasound scans. Management of EHIT depended on the EHIT class and differed widely among the physicians. CONCLUSIONS: Our nationwide survey on thromboprophylaxis practices after ETA of truncal varicose veins in Switzerland showed that most physicians use pharmacologic thromboprophylaxis, with a direct oral anticoagulant drug the preferred agent. However, the timing of the first dose and the duration of thromboprophylaxis varied widely among the respondents, reflecting the uncertainty in this domain owing to the absence of high-quality evidence-based guidelines.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Ablação por Cateter/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Padrões de Prática Médica , Tromboembolia/prevenção & controle , Varizes/cirurgia , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Estudos Transversais , Esquema de Medicação , Pesquisas sobre Atenção à Saúde , Humanos , Meias de Compressão , Suíça , Tromboembolia/diagnóstico por imagem , Ultrassonografia Doppler Dupla
4.
Swiss Med Wkly ; 149: w20166, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31869428

RESUMO

AIM OF THE STUDY: The objective of this study was to identify the optimal duration of pharmacological thromboprophylaxis after outpatient endovenous laser ablation (EVLA). METHODS: In this multicentre retrospective study in a university hospital, regional hospital and private practices, we collected the demographic, procedural and outcome data of all consecutive patients with varicose veins class C2 to C6 undergoing outpatient EVLA of truncal and accessory veins between February 2009 and December 2015. The cumulative primary efficacy endpoint consisted of endovenous heat-induced thrombosis (EHIT) class 2–4, deep vein thrombosis (DVT) and pulmonary embolism (PE) diagnosed with duplex ultrasound or computed tomography angiography after 1 and 4 weeks of follow-up. Cumulative secondary endpoints were complete ablation of the treated veins and major bleeding, skin burns and infection. RESULTS: A total of 864 patients were treated with EVLA as an outpatient procedure. Of those, 35 patients were omitted because of therapeutic anticoagulation or dual antiplatelet therapy. Another 36 cases were excluded as the patients received pharmacological thromboprophylaxis for 5 days. A total of 793 were included in the final analysis. Of those, 225 patients (28.4%) received fondaparinux 2.5 mg s.c. for 3 days, 166 patients (20.9%) received rivaroxaban 10 mg p.o. for 3 days and 402 patients (50.7%) received rivaroxaban 10 mg for 10 days. The incidence of EHIT class 2–4 was 0.8% (n = 6) in total, 1.3% (n = 6) in group 1 (treated for 3 days) and 0.3% (n = 1) in group 2 (treated for 10 days) (odds ratio [OR] 0.19, confidence interval [CI] 0.02–1.66, p = 0.133). The cumulative primary composite endpoint at 4-week follow-up was 1.1% (n = 9) and was 2.1% (n = 8) in group 1 and 0.3% (n = 1) in group 2 (OR 0.0.12, CI 0.01–0.96, p = 0.046). Propensity score-matched analysis revealed no significant difference in the composite primary endpoint (CI −0.074 to 0.26). Complete occlusion rate was 99.2% in group 1 and 98.8% in group 2 (OR 0.61, CI 0.15–2.59, p = 0.506). No PE or major bleeding events occurred in either group. Propensity score-matched analysis showed no significant difference in the secondary endpoints. CONCLUSION: Using propensity score-matched analysis we showed that pharmacological thromboprophylaxis after EVLA seems to be equally effective with 3 days or 10 days of treatment with a similar success rate and safety profile. Undoubtedly, a large randomised control trial, ideally including a group without pharmacological thromboprophylaxis, is needed to draw more definitive conclusions on the optimal duration of pharmacological post-EVLA thromboprophylaxis.


Assuntos
Inibidores do Fator Xa/administração & dosagem , Fondaparinux/administração & dosagem , Terapia a Laser , Rivaroxabana/administração & dosagem , Tromboembolia Venosa/prevenção & controle , Procedimentos Cirúrgicos Ambulatórios , Relação Dose-Resposta a Droga , Esquema de Medicação , Procedimentos Endovasculares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estudos Retrospectivos , Veia Safena/cirurgia , Varizes/cirurgia
5.
J Endovasc Ther ; 26(2): 181-190, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30741067

RESUMO

PURPOSE: To report the 1-year outcomes of a single-center, all-comers registry aimed to assess effectiveness and safety of endovascular revascularization for atherosclerotic erectile dysfunction (ED) in an unselected patient cohort. MATERIALS AND METHODS: Between April 2016 and October 2017, 50 consecutive patients (mean age 59.6±10.3 years) underwent endovascular revascularization for ED owing to >50% stenosis in 82 erection-related arteries. Patients were treated by means of standard balloon angioplasty (16%), drug-coated balloon angioplasty (27%), or drug-eluting stent (55%) implantation. The primary feasibility outcome measure was the incidence of a minimum clinically relevant improvement of ≥4 in the 6-question International Index of Erectile Function Questionnaire (IIEF-6) score at 12 months. Clinical effectiveness was improvement in erectile function as quantified in the mean difference (MD) of the IIEF-15 score at 3 and 12 months as well as the mean changes in IIEF-15 questions 3 and 4. RESULTS: Procedure success was achieved in 49 (98%) of 50 patients. At 12 months, 30 (65%) of 46 patients achieved a minimum clinically relevant improvement in the IIEF-6 score. The overall IIEF-15 score, as well as scores for questions 3 and 4, improved in 32 (65%) of 49 patients, 28 (57%) of 49 patients, and 29 (60%) of 48 patients, respectively. Change in the overall IIEF-15 score at 12 months was consistent among subgroups, except for elderly patients [MD -5.0 (95% CI -9.7 to -0.2), p=0.041] and those with hypertension [MD -11.0 (95% CI -20.5 to -1.5), p=0.025], who showed less improvement. CONCLUSION: Endovascular revascularization was safe and efficacious in the majority of ED patients through 1 year.


Assuntos
Angioplastia com Balão , Impotência Vasculogênica/terapia , Ereção Peniana , Pênis/irrigação sanguínea , Doença Arterial Periférica/terapia , Idoso , Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/instrumentação , Tomada de Decisão Clínica , Materiais Revestidos Biocompatíveis , Constrição Patológica , Stents Farmacológicos , Estudos de Viabilidade , Humanos , Impotência Vasculogênica/diagnóstico por imagem , Impotência Vasculogênica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Estudos Prospectivos , Recuperação de Função Fisiológica , Sistema de Registros , Fatores de Risco , Suíça , Fatores de Tempo , Resultado do Tratamento , Dispositivos de Acesso Vascular
6.
J Endovasc Ther ; 25(6): 710-715, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30343612

RESUMO

PURPOSE: To evaluate the incidence of elastic recoil in patients presenting with erectile dysfunction (ED) undergoing endovascular revascularization of the pudendal or penile arteries. METHODS: A consecutive series of 21 ED patients (mean age 58.3±9.3 years) undergoing minimally invasive revascularization of 31 arteries was analyzed. ED lesions included the pudendal arteries (n=27) and the penile artery (n=4). Mean lesion length was 20.6±13.9 mm. Minimal lumen diameter (MLD) measurements were assessed at baseline, immediately after balloon angioplasty, and 10 minutes thereafter. Early recoil was defined as an MLD reduction >10%. Elastic recoil with >10% lumen compromise was treated with drug-coated balloons, while severe elastic recoil (>30%) required drug-eluting stents (DES). The International Index of Erectile Function (IIEF-15) score was obtained prior to and 3 months after the procedure to obtain information on functional outcomes subsequent to angioplasty. RESULTS: Mean MLD at baseline was 0.9±0.6 mm, which improved to 2.0±0.9 mm immediately after balloon dilation. At 10 minutes after dilation, the MLD was 1.7±1.0 mm. Elastic recoil was observed in all 31 lesions and resulted in a mean lumen compromise of 21.2%. Severe (>30%) recoil was observed in 14 arteries, which underwent DES therapy. The IIEF-15 score improved from 31.3±11.2 at baseline to 49.8±16.8 (p<0.001) at the 3-month follow-up. CONCLUSION: Endovascular revascularization constitutes a safe and feasible treatment modality to restore erectile function in patients with arteriogenic ED and ineffective conservative management. Early elastic recoil is very frequent subsequent to balloon dilation of small-caliber erection-related arteries. Thus, mechanical scaffolding with DES is required in a high subset of ED patients to provide favorable early angiographic and clinical results.


Assuntos
Angioplastia com Balão , Artérias , Impotência Vasculogênica/terapia , Ereção Peniana , Pênis/irrigação sanguínea , Idoso , Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/instrumentação , Artérias/diagnóstico por imagem , Artérias/fisiopatologia , Materiais Revestidos Biocompatíveis , Constrição Patológica , Stents Farmacológicos , Humanos , Impotência Vasculogênica/diagnóstico por imagem , Impotência Vasculogênica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recuperação de Função Fisiológica , Fluxo Sanguíneo Regional , Fatores de Tempo , Resultado do Tratamento , Dispositivos de Acesso Vascular
7.
J Vasc Surg Venous Lymphat Disord ; 5(6): 817-823, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29037351

RESUMO

OBJECTIVE: Endovenous heat-induced thrombosis (EHIT) and deep venous thrombosis (DVT) are well-known complications after superficial endovenous thermoablation. We investigated the efficacy of rivaroxaban in preventing EHIT and DVT after endovenous laser ablation (EVLA). METHODS: We retrospectively analyzed a consecutive series of patients presenting with truncal varicosis class C2 to C6 undergoing EVLA. After EVLA, all patients received oral rivaroxaban (10 mg) or subcutaneous fondaparinux (2.5 mg) once daily for 3 consecutive days. The primary end point was the composite of EHIT or DVT assessed by duplex ultrasound imaging after 1 and 4 weeks. EHIT class 1 was defined as the thrombus extending to the saphenofemoral junction. Extension into the deep venous system with a cross-sectional area obstruction <50% was considered EHIT class 2. EHIT class 3 was defined as >50% cross-sectional area obstruction. EHIT class 4 was total occlusion of the femoral vein. The secondary end points were minor or major bleeding, paresthesia, and skin burns. RESULTS: Between February 2009 and December 2015, 391 patients (473 limbs) were treated with EVLA of the truncal saphenous vein. The primary end point occurred in 13 of 166 (7.8%) and 14 of 225 (6.2%) after 1 week and in 13 of 166 (7.8%) and 15 of 225 (6.7%) after 4 weeks comparing the rivaroxaban and fondaparinux groups (P = .659). EHIT class 1 was observed in 20 patients (5.1%) and EHIT class 2 in five (1.3%). No patients had EHIT class 3 or 4. The incidence of DVT was one of 166 (0.6%) in the rivaroxaban group and two of 225 (0.9%) in the fondaparinux group (P = .750). Minor bleeding events occurred in 17 of 166 patients (10.2%) and in 20 of 225 patients (8.9%), respectively (P = .652). No major bleeding events were observed. Paresthesia was observed in 12.5% in the rivaroxaban group and in 17.8% in the fondaparinux group. No skin burns were observed. CONCLUSIONS: Rivaroxaban offers an oral medication approach showing no difference in preventing EHIT and DVT compared with fondaparinux, without increased bleeding risk.


Assuntos
Inibidores do Fator Xa/administração & dosagem , Terapia a Laser/efeitos adversos , Polissacarídeos/administração & dosagem , Rivaroxabana/administração & dosagem , Trombose Venosa/prevenção & controle , Administração Cutânea , Administração Oral , Procedimentos Endovasculares/efeitos adversos , Inibidores do Fator Xa/efeitos adversos , Feminino , Fondaparinux , Hemorragia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Polissacarídeos/efeitos adversos , Estudos Retrospectivos , Rivaroxabana/efeitos adversos , Veia Safena/cirurgia , Resultado do Tratamento , Varizes/cirurgia , Insuficiência Venosa/cirurgia
8.
Forsch Komplementmed ; 20 Suppl 2: 22-4, 2013.
Artigo em Alemão | MEDLINE | ID: mdl-23860109

RESUMO

Peripheral arterial occlusive disease (PAOD) is in about 90% of the cases caused by atherosclerosis. Since this can affect all arteries of the body, PAOD is considered an important indicator of cardiovascular events such as heart attack or stroke, and thus of the leading cause of death in the Western world. With the measurement of the ankle/brachial pressure index (ABI), a practicable method is available to diagnose the disease in routine practice. Besides lifestyle modifications, the mainstay of treatment of atherosclerosis includes also drug treatment of known risk factors. In case of a severe circulatory disorder with critical ischemia, a revascularization by angioplasty or surgical methods is imperative. If the walking distance is limited due to PAOD, we speak of intermittent claudication. Here, in addition to the interventional treatment (percutaneous transluminal angioplasty (PTA) / surgery), a conservative walking exercise can be performed. The supportive use of Padma 28 in the conservative treatment has a measurable effect with a significant extension of the maximum walking distance and poses an additive treatment option.


Assuntos
Arteriopatias Oclusivas/tratamento farmacológico , Fitoterapia/métodos , Extratos Vegetais/uso terapêutico , Arteriopatias Oclusivas/classificação , Arteriopatias Oclusivas/diagnóstico , Terapia Combinada , Angiopatias Diabéticas/tratamento farmacológico , Quimioterapia Combinada , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Qualidade de Vida , Caminhada
9.
Cells Tissues Organs ; 178(1): 48-59, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15550759

RESUMO

The four stages of the estrous cycle in Monodelphis domestica, namely proestrus, estrus, postestrus and the transitional metestrus, were analyzed with the scanning electron microscope and compared with the results of the previously published transmission electron-microscopic paper [Cells Tissues Organs 2002;172:276-296]. During the estrous cycle the vaginal epithelium undergoes dramatic changes from a nonkeratinized to a highly keratinized epithelium. The predominant feature of proestrus with the beginning of keratinization is the presence of polygonal flat cells with pavement-like appearance, bordered by raised ridges and covered with microvilli. The epithelium is fully keratinized in estrus, and the superficial layers overlap like shingles. Many cells are still densely covered by microvilli, whereas others develop a complex pattern of microridges. In postestrus different epithelial structures are revealed depending on the actual stage of desquamation. In early postestrus surface cells resemble those present during estrus. In late postestrus, when only few keratinized cells are left, the nonkeratinized cells become exposed to the lumen through desquamation. These cells border the lumen during metestrus, a cycle stage during which numerous leukocytes migrate into the vaginal canal. A number of these uppermost cells is probably not yet prepared to function as metestrus cells and are therefore sloughed off as well. During metestrus compact cell masses stick in the vaginal furrows. Epithelial surface cells are highly irregular and bulging with their microvilli covered surfaces in the vaginal lumen. This study represents the first comprehensive description of alterations on the surface ultrastructure of a marsupial vagina during the estrous cycle, demonstrating considerable differences in comparison to many eutherians.


Assuntos
Ciclo Estral , Monodelphis/anatomia & histologia , Animais , Epitélio/ultraestrutura , Ciclo Estral/metabolismo , Feminino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Útero/anatomia & histologia , Vagina/ultraestrutura
10.
Cells Tissues Organs ; 172(4): 276-96, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12566630

RESUMO

The vaginal complex of marsupials differs from that of eutherians. Cervices open separately in a sinus vaginalis or cul-de-sac. Two lateral vaginae adjoin the sinus vaginalis and fuse at the level of the urethra opening and form the sinus urogenitalis. During the estrous cycle the vaginal epithelium undergoes a number of specified morphological changes. This paper is the first to describe these changes on an ultrastructural level in a marsupial. Investigations in Monodelphis vagina reveal that a cyclic switch exists between a keratinized and a stratified nonkeratinized epithelium. Keratinization starts during proestrus and reaches its maximum during estrus. In the postestrus, desquamation of the stratum corneum takes place, mostly in two steps. In metestrus one to two additional layers of the now nonkeratinized surface cells are shed into the vaginal lumen. Typical cell structures, such as keratin filaments, keratohyalin and membrane-coating granules, are involved in the keratinization process. Keratohyalin is found in the cytoplasm as well as in the nucleus of stratum granulosum cells, a phenomenon which is known from other parakeratinized epithelia of rapid turnover. Membrane-coating granules, responsible for the permeability barrier between the epithelial cells, are of the nonlamellated type in the nonkeratinized epithelium and produce an amorphous material in the intercellular spaces after extrusion. At periods, however, when the epithelium is keratinized, membrane-coating granules are of the lamellated type and form a lamellated barrier structure after extrusion in the intercellular space. The loss of the protective keratinized layers asks for an additional defense mechanism for the epithelium. The migration of leukocytes through the epithelium predominantly during post- and metestrus and their presence in the vaginal lumen may play a protective role together with the bacterial content.


Assuntos
Epitélio/metabolismo , Ciclo Estral/metabolismo , Gambás/metabolismo , Vagina/metabolismo , Animais , Epitélio/ultraestrutura , Feminino , Microscopia Eletrônica , Útero/metabolismo , Vagina/ultraestrutura
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