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1.
Breast J ; 2023: 6688466, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37205012

RESUMO

Purpose: In modern breast cancer treatment, a growing role has been observed for breast reconstruction together with an increase in clinical indications for postmastectomy radiotherapy (PMRT). Choosing the optimum type of reconstructive technique is a clinical challenge. We therefore conducted a national multicenter study to analyze the impact of PMRT on breast reconstruction. Methods: We conducted a retrospective case-control multicenter study on women undergoing breast reconstruction. Data were collected from 18 Italian Breast Centres and stored in a cumulative database which included the following: autologous reconstruction, direct-to-implant (DTI), and tissue expander/immediate (TE/I). For all patients, we described complications and surgical endpoints to complications such as reconstruction failure, explant, change in type of reconstruction, and reintervention. Results: From 2001 to April 2020, 3116 patients were evaluated. The risk for any complication was significantly increased in patients receiving PMRT (aOR, 1.73; 95% CI, 1.33-2.24; p < 0.001). PMRT was associated with a significant increase in the risk of capsular contracture in the DTI and TE/I groups (aOR, 2.24; 95% CI, 1.57-3.20; p < 0.001). Comparing type of procedures, the risk of failure (aOR, 1.82; 95% CI, 1.06-3.12, p=0.030), explant (aOR, 3.34; 95% CI, 3.85-7.83, p < 0.001), and severe complications (aOR, 2.54; 95% CI, 1.88-3.43, p < 0.001) were significantly higher in the group undergoing DTI reconstruction as compared to TE/I reconstruction. Conclusion: Our study confirms that autologous reconstruction is the procedure least impacted by PMRT, while DTI appears to be the most impacted by PMRT, when compared with TE/I which shows a lower rate of explant and reconstruction failure. The trial is registered with NCT04783818, and the date of registration is 1 March, 2021, retrospectively registered.


Assuntos
Neoplasias da Mama , Mamoplastia , Feminino , Humanos , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Neoplasias da Mama/etiologia , Radioterapia Adjuvante/efeitos adversos , Radioterapia Adjuvante/métodos , Mastectomia/métodos , Estudos Retrospectivos , Resultado do Tratamento , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Mamoplastia/efeitos adversos , Mamoplastia/métodos
2.
Aesthet Surg J ; 43(6): 665-672, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242548

RESUMO

BACKGROUND: Secondary cosmetic breast surgery after primary augmentation with implant can be associated with an increased risk of adverse events. Partial/complete nipple-areola complex necrosis is particularly feared. In this preliminary study, the authors propose the utilization of indocyanine green (ICG) angiography to assess the blood supply of breast tissue after implant removal. OBJECTIVES: The main objective was to prevent skin and gland necrosis in revision breast surgery. METHODS: The authors performed a retrospective comparative analysis of 33 patients who underwent secondary breast surgery between 2018 and 2021 by a single surgeon (M.S.). Breast tissue perfusion was assessed in 16 patients by intraoperative ICG angiography at the end of implant removal and possible capsulectomy. Non-stained/non-fluorescent areas were judged to be low perfusion areas and were excised with short scar mastopexy. RESULTS: In the ICG angiography group, 7 patients (44%) showed an area of poor perfusion along the inferior pole; all of these patients underwent subglandular breast augmentation. Resection of the poor perfusion areas allowed an uneventful postoperative course. In the non--- ICG angiography group (17 patients), 5 patients experienced vertical-scar dehiscence/necrosis. We found a statistically significant association between the non-ICG angiography group and vertical scar dehiscence/necrosis, and also between vertical scar dehiscence/necrosis and subglandular implant placement (P = 0.04). CONCLUSIONS: Safer secondary surgery can be offered to patients undergoing secondary aesthetic breast procedures, especially when the first augmentation surgery is unknown-for example, implant plane, type of pedicle employed, if the implant is large and subglandular, and if capsulectomy is performed.


Assuntos
Neoplasias da Mama , Mamoplastia , Humanos , Feminino , Estudos Retrospectivos , Cicatriz/etiologia , Mamoplastia/efeitos adversos , Mamoplastia/métodos , Neoplasias da Mama/cirurgia , Angiografia , Mamilos/cirurgia , Necrose/etiologia , Necrose/prevenção & controle , Necrose/cirurgia , Estética , Verde de Indocianina , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/cirurgia
3.
Biodegradation ; 33(6): 609-620, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36197531

RESUMO

The biodegradation of rubber materials is considered as a sustainable recycling alternative, highlighting the use of microorganisms and enzymes in oxidative processes of natural rubber. Currently, the main challenge is the treatment of rubber materials such as waste tyres, where the mixture of rubber polymers with different additives and the cross-linked structure obtained due to the vulcanisation process positions them as highly persistent materials. This study characterises the degradation of different rubber-containing substrates in in vivo and in vitro processes using the bacterium Rhodococcus rhodochrous and the oxygenase latex clearing protein (Lcp) from the same strain. For the first time, the degradation of polyisoprene particles in liquid cultures of R. rhodochrous was analysed, obtaining up to 19.32% mass loss of the polymer when using it as the only carbon source. Scanning electron microscopy analysis demonstrated surface alteration of pure polyisoprene and vulcanised rubber particles after 2 weeks of incubation. The enzyme LcpRR was produced in bioreactors under rhamnose induction and its activity characterised in oxygen consumption assays at different enzyme concentrations. A maximum consumption of 28.38 µmolO2/min was obtained by adding 100 µg/mL LcpRR to a 2% (v/v) latex emulsion as substrate. The bioconversion of natural rubber into reaction degradation products or oligoisoprenoids was calculated to be 32.54%. Furthermore, the mass distribution of the oligoisoprenoids was analysed by liquid chromatography coupled to mass spectrometry (LC-MS) and 17 degradation products, ranging from C20 to C100 oligoisoprenoids, were identified. The multi-enzymatic degradation capacity of R. rhodochrous positions it as a model microorganism in complex degradation processes such as in the case of tyre waste.


Assuntos
Látex , Rhodococcus , Látex/metabolismo , Biodegradação Ambiental , Ramnose/metabolismo , Emulsões/metabolismo , Borracha , Proteínas de Bactérias/metabolismo , Rhodococcus/metabolismo , Oxigenases/química , Carbono/metabolismo
4.
Facial Plast Surg ; 37(3): 400-406, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33706387

RESUMO

In the field of facial rejuvenation, among the recurrent topics, one of the most discussed is the return to less invasive techniques. Lower face rejuvenation is best achieved acting on the platysma muscle. Many techniques are used and usually include platysma section, redundancy reduction, and redraping. Platysma plication is also used especially in secondary cases because of the increased risk of nerve injury due to possible anatomical damage caused by previous operations. A technique that preserves the deep planes based on a new plication method is proposed (conservative neck rejuvenation). In this technique, the dissection plane is only subcutaneous to reduce the risk of nerve injuries. An effective neck contouring is possible using a simpler technique with very good results and a lower rate of morbidity.


Assuntos
Ritidoplastia , Sistema Musculoaponeurótico Superficial , Humanos , Pescoço/cirurgia , Músculos do Pescoço/cirurgia , Rejuvenescimento , Sistema Musculoaponeurótico Superficial/cirurgia
5.
J Reconstr Microsurg ; 37(5): 436-444, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33058098

RESUMO

BACKGROUND: After anterolateral thigh (ALT) flap harvesting, skin graft of the donor site is commonly performed. When the defect width exceeds 8 cm or 16% of thigh circumference, it can determine lower limb function impairment and poor aesthetic outcomes. In our comparative study, we assessed the functional and aesthetic outcomes related to ALT donor-site closure with split-thickness skin graft compared with thigh propeller flap. METHODS: We enrolled 60 patients with ALT flap donor sites. We considered two groups of ALT donor-site reconstructions: graft group (30 patients) with split-thickness skin graft and flap group (30 patients) with local perforator-based propeller flap. We assessed for each patient the range of motion (ROM) at the hip and knee, tension, numbness, paresthesia, tactile sensitivity, and gait. Regarding the impact on daily life activities, patients completed the lower extremity functional scale (LEFS) questionnaire. Patient satisfaction for aesthetic outcome was obtained with a 5-point Likert scale (from very poor to excellent). RESULTS: In the propeller flap group, the ROMs of hip and knee and the LEFS score were significantly higher. At 12-month follow-up, in the graft group, 23 patients reported tension, 19 numbness, 16 paresthesia, 22 reduction of tactile sensitivity, and 5 alteration of gait versus only 5 patients experienced paresthesia and 7 reduction of tactile sensitivity in the propeller flap group. The satisfaction for aesthetic outcome was significantly higher in the propeller flap group. CONCLUSION: In high-tension ALT donor-site closure, the propeller perforator flap should always be considered to avoid split-thickness skin graft with related functional and aesthetic poor results.


Assuntos
Retalho Perfurante , Procedimentos de Cirurgia Plástica , Humanos , Estudos Retrospectivos , Transplante de Pele , Coxa da Perna/cirurgia , Resultado do Tratamento
6.
J Obstet Gynaecol Res ; 45(7): 1398-1403, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30916459

RESUMO

Mayer-Rokitansky-Küster-Hauser syndrome is characterized by aplasia of the uterus and the upper ⅔ of the vagina, with normal female genotype (46,XX) and the development of secondary sexual characters. One of the most popular surgical treatment is the McIndoe procedure, which major drawbacks are the scar of split thickness skin graft (STSG)harvesting, and risk of vaginal stenosis for graft retraction. We report the case of a patient, operated modifying the McIndoe technique, by harvesting a full thickness skin grafts (FTSG) from patient's breasts, undergone simultaneous reduction mammoplasty. The FTSG provided a complete lining of the reconstructed neovagina. At 6 months, we observed complete mucinous metaplasia of the vaginal walls and 1 year after surgery no sign of stenosis, without the use of the mold. The advantages of this technique are reduced donor site morbidity, when compared with traditional McIndoe technique, and reduced risk of neovagina retraction ensured by FTSG, compared with STSG. If future patients' series confirm the good results achieved, we could consider it as a first-line option in patients undergoing neovagina reconstruction, seeking breasts or body contouring surgery.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual/cirurgia , Doenças Mamárias/cirurgia , Anormalidades Congênitas/cirurgia , Ductos Paramesonéfricos/anormalidades , Procedimentos de Cirurgia Plástica/métodos , Transplante de Pele/métodos , Vagina/anormalidades , Transtornos 46, XX do Desenvolvimento Sexual/complicações , Transtornos 46, XX do Desenvolvimento Sexual/patologia , Doenças Mamárias/congênito , Doenças Mamárias/patologia , Terapia Combinada , Anormalidades Congênitas/genética , Anormalidades Congênitas/patologia , Estética , Feminino , Humanos , Hipertrofia , Ductos Paramesonéfricos/patologia , Ductos Paramesonéfricos/cirurgia , Vagina/cirurgia , Adulto Jovem
7.
Microsurgery ; 39(7): 605-612, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31400162

RESUMO

INTRODUCTION: Pelvic lymphadenectomy (PL) causes changes to the inguinal lymph nodes with progressive loss of immune and lymphatic pump function. Efferent lymphatic vessel-to-venous anastomosis (ELVA) has been reported to address this problem. The aim of this report was to describe the feasibility of the SPECT/CT combined with ultrasound fusion imaging (UFI) to target the groin efferent lymph node (GELN) for ELVA. PATIENTS AND METHODS: Twelve patients with lower limb lymphedema after PL were scheduled for peripheric lymphaticovenular anastomosis (LVA) combined with ELVA. All-patients were clinically ISL-stage1, with good visualization of the inguinal lymph nodes at preoperative lymphoscintigraphy. The mean patient age was 55.4 years and the mean BMI was 25.5.The mean limb circumference (MLC) was calculated before surgery and 1 year after surgery. The LymQoL-Leg questionnaire was administered before surgery and 6 months after surgery. Before surgery, the GELN was identified by SPECT/CT and its location was marked on the skin by UFI virtual navigation. Peripheric LVA sites were planned by ultrasound and indocyanine green (ICG) lymphography. Pre and postoperative MLC and LymQoL-Leg scores were compared. RESULTS: In all-patients, the SPECT/CT succeeded at detecting and targeting the GELN. In all-patients, real-time anatomical coregistration with US was feasible, and it was possible to mark on the groin skin the depth and position of the GELN on the skin at the groin. During surgery, in every patient, we found the GELN marked before surgery and performed ELVA. We also performed two or three peripheric LVAs in every patient. The mean value of MLC decreased (38.2 ± 2.13 cm vs. 36.33 ± 2.14 cm; p = .04) and the mean score of the LymQoL-Leg questionnaire improved (9.3 ± 1.7 vs. 7.7 ± 1.1; p = .02). CONCLUSION: SPECT/CT combined with UFI is feasible for the preoperative identification of GELN for ELVA.


Assuntos
Excisão de Linfonodo , Linfonodos/diagnóstico por imagem , Linfedema/diagnóstico por imagem , Linfedema/cirurgia , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Ultrassonografia , Adulto , Idoso , Anastomose Cirúrgica , Estudos de Viabilidade , Feminino , Virilha , Humanos , Extremidade Inferior , Linfonodos/cirurgia , Masculino , Pessoa de Meia-Idade
8.
Microsurgery ; 39(5): 447-451, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30957283

RESUMO

Several different flaps based on the feeding vessels of sensitive nerves have been described in the limbs. This article reports the case of a neurocutaneous flap based on the lateral femoral cutaneous nerve (LFCN), employed for reconstruction of an inguinal defect. A 61-years-old female patient had undergone vulvectomy and bilateral inguinal lymphadenectomy for vulvar cancer with postoperative left groin wound breakdown. After a 3 weeks negative pressure therapy course, she presented a 10 × 4 cm skin and subcutaneous defect with undermined edges in the left inguinal area. Reconstruction with 14 × 6 cm pedicled left anterolateral thigh flap was planned. After the dissection of the vascular pedicle and of the sensitive nerve, complete thrombosis of both the veins and arterial spasm of perforating pedicle was detected. As the flap color was good, and slow marginal bleeding was present, we inspected the small vessels surrounding the nerve that were pulsating. To confirm the vascularization coming from the neural pedicle, we clamped the perforator and performed intraoperative indocyanine green (ICG) fluorescence angiography that showed a good fluorescence of the flap with a proximal to distal pattern of progression. The flap was transferred on the neural pedicle, survived completely, and wounds healed normally. Three months after surgery, the patient underwent radiotherapy, with uneventful course. In her last follow-up, 2 years after surgery, patient was free of disease and the flap showed normal scarring. This is the first case reported of a pedicled neurocutaneous flap based on the LFCN, indicating that in case of unsuitable perforators it could be an alternative pedicle.


Assuntos
Virilha/cirurgia , Linfonodos/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/transplante , Neoplasias Vulvares/cirurgia , Feminino , Seguimentos , Sobrevivência de Enxerto , Virilha/fisiopatologia , Humanos , Excisão de Linfonodo/efeitos adversos , Excisão de Linfonodo/métodos , Pessoa de Meia-Idade , Medição de Risco , Transplante de Pele/métodos , Retalhos Cirúrgicos/inervação , Resultado do Tratamento , Neoplasias Vulvares/diagnóstico , Vulvectomia/efeitos adversos , Vulvectomia/métodos , Cicatrização/fisiologia
9.
J Reconstr Microsurg ; 35(9): 669-676, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31315137

RESUMO

BACKGROUND: The superficial circumflex iliac perforator (SCIP) flap has many ideal features, such as fast dissection, possibility to harvest thin, pliable, wide skin island, and concealed donor site scar. In spite of these features, its use was limited because of the wide anatomical variation of the pedicle, which is relatively shorter and has a smaller caliber than other more popular perforator flaps. Several names were given to the branches and perforators in the literature, thus adding confusion to the understanding of its anatomy. METHODS: We performed a surgical and a radioanatomical study of the SCIP pedicles analyzing high-resolution contrast-enhanced computed tomography (CT) scan of 95 groins, with particular attention to the deep branch (DB) of the superficial circumflex iliac artery (SCIA). Twenty-three of these patients were also studied by detecting the surgical anatomy during SCIP flap harvest. We employed a system of coordinates based on the line between pubic tubercle (PT) and anterior superior iliac spine (ASIS) to describe the position of the perforator of the DB. RESULTS: We found a 100% correlation between surgical and radiological findings. The length of the DB from the origin to the point in which its perforator pierced the sartorius fascia ranged from 1.6 to 6.5 cm, mean = 3.62 ± 0.92 cm. The distance between the origin of the DB and the inguinal ligament ranged from 1.1 to 7.5 cm, mean = 2.8 ± 1 cm. The perforator of the DB could be found in 91% of the cases within a box of 4 cm × 3 cm drawn caudally to the line joining the PT with the ASIS. This vessel can show a vertical or horizontal course in the subcutaneous layer. CONCLUSION: Our findings confirm other previous studies and add new information about the position and the course of the perforator of the DB of the SCIA. Important features of the SCIP pedicles can be investigated by the color Doppler ultrasound and CT scan.


Assuntos
Angiografia por Tomografia Computadorizada , Artéria Ilíaca/anatomia & histologia , Artéria Ilíaca/diagnóstico por imagem , Retalho Perfurante/irrigação sanguínea , Ultrassonografia Doppler em Cores , Adulto , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos , Meios de Contraste , Feminino , Virilha/irrigação sanguínea , Virilha/diagnóstico por imagem , Humanos , Artéria Ilíaca/cirurgia , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
10.
J Reconstr Microsurg ; 34(9): 701-707, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29689576

RESUMO

BACKGROUND: Lymphedema is a progressive disease that negatively affects body image and physical, psychological, and social functions. There is lack of evidence in the present literature about the impact of super microsurgical lymphaticovenular anastomosis (LVA) on health-related quality of life (HRQoL). The aim of this prospective study is to report the outcomes of patients' HRQoL after LVA for lower and upper extremities lymphedema. METHODS: Between September 2015 and February 2017, 74 patients with upper or lower limb lymphedema (ULL or LLL) underwent LVA at our center. Quality of life (QoL) was assessed by lymphedema QoL questionnaire (LyMQoL), which is a validated disease-specific instrument to measure the impact of lymphedema on patient's lives, covering four domains: function, body image, symptoms, and mood. All patients were evaluated preoperatively, 1 month after surgery, and every 3 months up to 1 year. Additionally, we evaluated the episodes of lymphangitis and the need for conservative therapy before and after surgery. RESULTS: After a mean follow-up of 8.5 months (range: 2-21 months), we observed an increase of 2.3 points in the overall QoL average for upper limb and 2.6 points for lower limb (p < 0.001). A statistically significant improvement in all four domains (p < 0.01) was reported after surgery, being present from the first postoperative months for both upper and lower extremities. CONCLUSION: Our study shows that lymphaticovenular anastomosis improves HRQoL in patients affected by ULL and LLL. Additionally, both a reduction of episodes of lymphangitis and a decrease in the need of conservative therapy were observed in this cohort of patients.


Assuntos
Anastomose Cirúrgica , Extremidade Inferior/cirurgia , Vasos Linfáticos/cirurgia , Linfedema/cirurgia , Microcirurgia , Qualidade de Vida , Extremidade Superior/cirurgia , Adulto , Idoso , Anastomose Cirúrgica/métodos , Feminino , Seguimentos , Humanos , Extremidade Inferior/fisiopatologia , Linfedema/fisiopatologia , Linfedema/psicologia , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente/estatística & dados numéricos , Estudos Prospectivos , Qualidade de Vida/psicologia , Resultado do Tratamento , Extremidade Superior/fisiopatologia , Adulto Jovem
11.
Clin Breast Cancer ; 23(2): e37-e44, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36610826

RESUMO

We report our experience in direct-to-implant breast reconstruction with prepectoral polyurethane implants, with a focus on intraoperative mastectomy flap thickness compared to preoperative data (flap thickness ratio) as a reliable predictive variable of ischemic complications and reconstructive outcomes (satisfaction with breast). BACKGROUND: The optimization of nipple sparing mastectomy and implant-based reconstruction techniques led to an increase in the popularity of prepectoral reconstruction. The aim of this study is to explore the ratio between the intraoperative and preoperative breast tissue coverage assessment as reliable tool in order to predict the risk of ischemic complications in prepectoral reconstruction. METHODS: We analyzed 124 preoperative digital mammograms of 100 patients who underwent prepectoral implant-based reconstruction. We applied a Rancati modified score for breast tissue coverage classification, adding 4 measurements on the craniocaudal view. The intraoperative mastectomy flap thickness was measured using an intraoperative ultrasound assessment. We investigated the differences between the groups with and without ischemic complications related to the preoperative, intraoperative, and flap thickness ratio data. RESULTS: The flap thickness ratio was lower in ischemic complication group compared to no ischemic complication group (0.4 vs. 0.8) with statistically significant differences for all ischemic complication subgroups: major mastectomy flap necrosis (P = .000), minor mastectomy flap necrosis (P = .005), partial nipple areola complex necrosis (P = .007), and implant exposure (P = .001).


Assuntos
Implantes de Mama , Neoplasias da Mama , Mamoplastia , Humanos , Feminino , Mamilos/diagnóstico por imagem , Mamilos/cirurgia , Mastectomia/efeitos adversos , Mastectomia/métodos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Estudos Retrospectivos , Mamoplastia/métodos , Necrose/cirurgia
12.
Int J Biol Macromol ; 242(Pt 1): 124626, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37119884

RESUMO

Fruit residues are attractive substrates for the production of bacterial polyhydroxyalkanoates due to the high contents of fermentable sugars and the fast, simple, and efficient pretreatment methods required. In this study, apple residues, mainly apple peel, were used as the sole carbon source in cultures of the bacterium Azotobacter vinelandii OP to produce poly-3-hydroxybutyrate (P3HB). Conversion from the residue to total sugars was highly effective, achieving conversions of up to 65.4 % w w-1 when using 1 % v v-1 sulfuric acid and 58.3 % w w-1 in the absence of acid (only water). The cultures were evaluated at the shake-flask scale and in 3-L bioreactors using a defined medium under nitrogen starvation conditions. The results showed the production of up to 3.94 g L-1 P3HB in a bioreactor, reaching an accumulation of 67.3 % w w-1 when using apple residues. For the PHB obtained from the cultures with apple residues, a melting point of 179.99 °C and a maximum degradation temperature of 274.64 °C were calculated. A P3HB production strategy is shown using easily hydrolysable fruit residues to achieve production yields comparable to those obtained with pure sugars under similar cultivation conditions.


Assuntos
Azotobacter vinelandii , Malus , Poli-Hidroxialcanoatos , Azotobacter vinelandii/metabolismo , Malus/metabolismo , Reatores Biológicos/microbiologia , Poliésteres/química , Hidroxibutiratos/química , Açúcares/metabolismo
13.
Polymers (Basel) ; 14(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35160364

RESUMO

The strong environmental impact caused by plastic pollution has led research to address studies from different perspectives. The mathematical modeling of the biodegradation kinetics of solid materials is a major challenge since there are many influential variables in the process and there is interdependence of microorganisms with internal and external factors. In addition, as solid substrates that are highly hydrophobic, mass transfer limitations condition degradation rates. Some mathematical models have been postulated in order to understand the biodegradation of plastics in natural environments such as oceans. However, if tangible and optimizable solutions are to be found, it is necessary to study the biodegradation process under controlled conditions, such as using bioreactors and composting systems. This review summarizes the biochemical fundamentals of the main plastics (both petrochemical and biological origins) involved in biodegradation processes and combines them with the main mathematical equations and models proposed to date. The different biodegradation studies of plastics under controlled conditions are addressed, analyzing the influencing factors, assumptions, model developments, and correlations with laboratory-scale results. It is hoped that this review will provide a comprehensive overview of the process and will serve as a reference for future studies, combining practical experimental work and bioprocess modeling systems.

14.
J Plast Reconstr Aesthet Surg ; 75(3): 1083-1093, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34838502

RESUMO

Capsular contracture, a common complication of breast implant reconstruction following postmastectomy radiotherapy (PMRT), represents a challenge for plastic surgeons. Regenerative surgery with multiple autologous fat grafts (lipobed) before replacing the implant has been proven to be a satisfactory approach in the radio-damaged breast. Currently, in literature, there are no data available on the histological features of irradiated capsules after regenerative surgery. We enrolled 80 patients after immediate subpectoral alloplastic breast reconstruction, with indication for revision surgery due to grade IV capsular contracture developed after PMRT. Forty patients were undergoing multiple fat grafting (lipobed group, mean age 48) and 40 patients were not undergoing multiple fat grafting (non-regenerative surgery (NRS) group, mean age 49). The removed capsules were addressed to histological and immunohistochemical assessment. The capsules of the lipobed group patients compared with NRS group patients showed: a lower mean thickness (602.17 versus 670.43 µm; P = 0.013), a lower collagen fiber alignment (median value of angle deviation: 30.34 versus 18.38; P = 0.001), a lower immunohistochemical positivity for myofibroblasts (α-smooth muscle actin [α-SMA] expression: 12.5% versus 52.5%; P = 0.00), a higher immunohistochemical positivity for estrogen receptor-ß (ER-ß; 80% versus 20%; P = 0.00), and a lower immunohistochemical positivity for estrogen receptor-α (ER-α; 53.3% versus 16.7%; P = 0.00). The histological and immunohistochemical differences found are possibly due to alterations in the extracellular microenvironment determined by grafted fat.


Assuntos
Implante Mamário , Implantes de Mama , Neoplasias da Mama , Mamoplastia , Tecido Adiposo/patologia , Implante Mamário/efeitos adversos , Implantes de Mama/efeitos adversos , Neoplasias da Mama/complicações , Neoplasias da Mama/cirurgia , Cápsulas , Feminino , Humanos , Contratura Capsular em Implantes/etiologia , Contratura Capsular em Implantes/patologia , Mamoplastia/efeitos adversos , Mastectomia/efeitos adversos , Pessoa de Meia-Idade , Estudos Retrospectivos , Microambiente Tumoral
15.
J Plast Reconstr Aesthet Surg ; 73(3): 556-562, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31668834

RESUMO

Patients undergoing revision rhinoplasty can show complex tip deformities such as asymmetry, dome angulation with cartilage interruption, alar pinch and retraction, and underprojection. When these defects are present at the same time, often multiple cartilage grafts are needed to restore a pleasing tip and functional external nasal valve. This study reports our experience with the rainbow graft, a previously described technique that can repair with a single cartilage graft the above-mentioned defects. We performed a retrospective review of 21 patients who had undergone revision rhinoplasty between 2006 and 2017 employing the rainbow graft technique to correct complex tip deformities. The presence of tip deformities such as asymmetry, dome angulation with cartilage interruption, alar pinch, alar retraction, and under/overprojection was recorded preoperatively and postoperatively. Complete photographic documentation was done, and Rhinoplasty Outcome Evaluation (ROE) questionnaire was administered to the patients. Five patients were male and 16 were females. Mean age of patients was 40 ± 7.6 years. Follow-up ranged from 1 to 12 years, mean 5 ±â€¯3 years. Eight patients had undergone one rhinoplasty, 10 patients had undergone two, and three patients had undergone three. Before surgery, all patients showed asymmetry, 20 dome angulation, 19 alar pinch, and 18 retraction. Eight showed tip overprojection, six underprojection, and seven no alteration of tip projection. The mean ROE score was 20.23 ± 7.37. After surgery, two patients showed persistent asymmetry, none had dome angulation, one alar pinch, and two alar retraction. Projection was corrected in every patient. We observed no case of graft infection, malposition, or resorption, and corrections achieved remained stable during follow-up. Mean postoperative ROE score was 80.75 ± 6.24. Its improvement was statistically significant (p < 0.001). The rainbow graft is a safe and effective technique in revision rhinoplasty indicated for the total restoration of nasal tip appearance in the presence of complex secondary deformities.


Assuntos
Cartilagem da Orelha/transplante , Procedimentos de Cirurgia Plástica/métodos , Reoperação/métodos , Rinoplastia/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nariz/cirurgia , Satisfação do Paciente , Estudos Retrospectivos
16.
Stem Cells Int ; 2019: 1579102, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467557

RESUMO

Clonal development (clonogenicity) is an inherent property of a subset of postnatal bone marrow (BM) adherent stromal mesenchymal stem cells (MSCs) from which a multipotent progeny develops in culture. Our data suggest that clonogenicity and BM-MSC expansion are two distinct biological events. This hypothesis is based on the following observations: (1) the beginning of clonal growth is a property strictly dependent on serum and independent of the social context, (2) the expansion of individual clone is influenced by events deriving from a social context during initial growth, (3) clonogenic cells grown in a social context in presence of serum can emancipate themselves to generate a secondary different progeny, and (4) the ability of socially generated clones to develop an inherent potential for further growth suggests that quorum sensing may operate in BM-MSC cultures and determine the potential growth of clonal strains.

17.
Cancers (Basel) ; 11(6)2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31159336

RESUMO

: Subendothelial cells (pericytes) are the clonogenic, multipotent and self-renewing skeletal stem cells (SSCs) found in bone marrow (BM) stroma. They express genes maintaining hematopoietic stem cell (HMC) niche identity and, transplanted in immunocompromised mice, organize the hematopoietic microenvironment (HME) generating humanized bone/BM ossicles. To create a mouse model of hematogenous metastasis of human prostate cancer (PC) cells to human bone/BM, we injected PC cells in the blood circulatory system of Severe Combined Immunodeficiency (SCID)/beige mice bearing heterotopic ossicles. Results indicate that PC cells could efficiently home to mice-implanted extraskeletal BM ossicles, but were not able to colonize mice skeletal segments. In humanized bone/BM ossicles, early foci of PC cells occupied a perisinusoidal position, in close contact with perivascular stromal cells. These findings demonstrate the importance of the SSC compartment in recreating a suitable environment to metastatic PC cells. Our data support the hypothesis that BM SSCs committed to a pericyte fate can specify for homing niches of PC cells, suggesting an involvement of specific interactions with subendothelial stromal cells in extravasation of circulating metastatic PC cells to BM.

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