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In this study, Bacillus tequilensis TB5 α-amylase from rice-milled by-products (rice bran and de-oiled rice bran) was successfully immobilized onto biologically synthesized magnetic nanoparticles fabricated with chitosan (MNP-Ch) and characterized via different biophysical techniques. Furthermore, the study emphasized incorporating this nanostructure framework (MNP@2mgchitosan_DORB-amy and MNP@3mgchitosan_RB-amy) to offer diverse applications, including enzymatic desizing, cleaning starchy stains, and treating synthetic starchy wastewater. An enzyme loading of > 90 % for both enzymes indicated increased binding sites due to the functional moieties of chitosan on the MNP. The Km was 0.28 and 0.31 mg/mL for the immobilized and free forms of DORB-amy, respectively, and 0.18 and 0.27 mg/mL for the immobilized and free forms of RB-amy, respectively. A low Km indicated an increased affinity of MNP-Ch-immobilized forms of enzymes toward the substrate. The performance of both immobilized enzymes improved at a wide range of pH and temperature, which may be attributed to the covalent binding of the enzyme on to the MNP-Ch. The nanobiocatalysts in the detergent act synergistically to fade the starchy stains. Furthermore, an 8-9 TEGEWA scale rating with > 11 % of starch removal was obtained through the biodesizing of starch-sized cotton fabric. The nanobiocatalyst efficiently decomposed starch and liberated 650-670 mg/L of reducing sugar from the synthetic wastewater, therefore offering promising opportunities for its exploration in a wastewater treatment plant. Thus, the study recommends the potential exploration of sturdy matrices like MNP to offer remarkable applications with maximum operational stability, easier recovery, and higher efficiency.
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Bacillus , Biocatálise , Quitosana , Detergentes , Enzimas Imobilizadas , Amido , Águas Residuárias , alfa-Amilases , alfa-Amilases/metabolismo , alfa-Amilases/química , Quitosana/química , Águas Residuárias/química , Amido/química , Amido/metabolismo , Bacillus/enzimologia , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Detergentes/química , Nanopartículas de Magnetita/química , Têxteis , Estrutura Molecular , Purificação da Água/métodos , Concentração de Íons de HidrogênioRESUMO
BACKGROUND: Identifying at-risk patients for complications remains challenging in patients with chronic lower extremity (LE) wounds receiving free tissue transfer (FTT) for limb salvage. The modified-5 frailty index (mFI-5) has been utilized to predict postoperative complications, yet it has not been studied in this population. The aim of this study was to determine the utility of the mFI-5 in predicting adverse postoperative outcomes. METHODS: Patients ≥60 years, who underwent LE FTT reconstruction at a single institution from 2011 to 2022, were retrospectively reviewed. Patient characteristics, mFI-5, and postoperative outcomes were collected. Cohorts were divided by an mFI-5 score of <2 or ≥2. RESULTS: A total of 115 patients were identified, of which 71.3% (n = 82) were male, 64.3% (n = 74) had a mFI-5 score of ≥2, and 35.7% (n = 41) had a score <2. The average age and body mass index were 67.8 years and 28.7 kg/m2 , respectively. The higher mFI-5 cohort had lower baseline albumin levels (3.0 vs. 4.0 g/dL, p = .015) and higher hemoglobin A1c levels (7.4 vs. 5.8%, p < .001). The postoperative length of stay was longer in the higher mFI-5 cohort (18 vs. 13.4 days, p = .003). The overall flap success was 96.5% (n = 111), with no difference between cohorts (p = .129). Postoperative complications were comparable between cohorts (p = .294). At a mean follow-up of 19.8 months, eight patients (7.0%) underwent amputation, and 91.3% (n = 105) were ambulatory. CONCLUSION: High microsurgical success rates can be achieved in comorbid patients with high frailty indexes who undergo FTT for limb salvage. A multidisciplinary team approach may effectively mitigate negative outcomes in elderly, frail patients.
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Fragilidade , Humanos , Masculino , Idoso , Feminino , Fragilidade/complicações , Fragilidade/diagnóstico , Medição de Risco , Estudos Retrospectivos , Fatores de Risco , Extremidade Inferior/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologiaRESUMO
BACKGROUND: In patients with chronic lower extremity (LE) wounds, chronic osteomyelitis confers additional complexity to achieving adequate treatment. Previous reviews demonstrate increased rates of osteomyelitis recurrence in patients who receive muscle flaps compared with fasciocutaneous flaps for LE limb salvage; however, these studies were not limited to atraumatic populations who receive exclusively free flaps. Thus, this study compared rates of recurrence in chronic osteomyelitis patients undergoing LE reconstruction with fasciocutaneous versus muscle free flaps. METHODS: Patients undergoing free tissue transfer (FTT) between July 2011 and July 2021 were retrospectively reviewed. Patients were stratified into fasciocutaneous and muscle free flap groups. Primary outcomes included osteomyelitis recurrence, flap complications, limb salvage, and ambulatory status. RESULTS: Forty-eight patients with pathologic diagnosis of chronic osteomyelitis of the wound bed were identified, of which 58.3% received fasciocutaneous (n = 28) and 41.7% received muscle flaps (n = 20). The most common comorbidities included diabetes mellitus (n = 29, 60.4%), peripheral neuropathy (n = 27, 56.3%) and peripheral vascular disease (n = 24, 50.0%). Methicillin-resistant or methicillin -sensitive Staphylococcus aureus were the most common pathogen in 18.7% (n = 9) of procedures. The majority of patients underwent a median of three debridements followed by negative pressure wound therapy prior to receiving FTT. At a median follow-up of 16.6 months, the limb salvage and ambulatory rates were 79.2 (n = 38) and 83.3% (n = 40), respectively. The overall rate of microsurgical flap success was 93.8% (n = 45). Osteomyelitis recurred in 25% of patients (n = 12) at a median duration of 4.0 months. There were no significant differences in rates of osteomyelitis recurrence, flap complications, limb salvage, ambulation, and mortality. On multivariate analysis, flap composition remained a nonsignificant predictor of osteomyelitis recurrence (odds ratio: 0.975, p = 0.973). CONCLUSION: This study demonstrates that flap composition may not influence recurrence of osteomyelitis following free flap reconstruction of chronic LE wounds, suggesting that optimal flap selection should be based on wound characteristics and patient goals.
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Retalhos de Tecido Biológico , Traumatismos da Perna , Osteomielite , Procedimentos de Cirurgia Plástica , Humanos , Estudos Retrospectivos , Retalhos de Tecido Biológico/cirurgia , Osteomielite/cirurgia , Músculos , Traumatismos da Perna/cirurgia , Resultado do TratamentoRESUMO
BACKGROUND: Breast cancer-related lymphedema is the most common cause of lymphedema in the United States and occurs in up to 50% of individuals receiving axillary lymph node dissection (ALND). Lymphovenous bypass (LVB) at the time of ALND may prevent lymphedema, but long-term results and anastomotic patency are unclear. This study evaluates the feasibility and outcomes of performing immediate lymphatic reconstruction via coupler-assisted bypass (CAB). METHODS: This is a retrospective review of all patients undergoing prophylactic LVB following ALND at two tertiary care centers between 2018 and 2022. Patients were divided into cohorts based on whether they received the "standard" end-to-end (E-E) suturing or CAB technique. The primary outcome of interest was development of lymphedema. Quantitative and qualitative assessments for lymphedema were performed preoperatively and at 3, 6, 12, and 24 months postoperatively. RESULTS: Overall, 63 LVBs were performed, of which 24 lymphatics underwent immediate reconstruction via "CAB" and 39 lymphatics via "standard" end-to-end suture. Patient characteristics, including body mass index, and treatment characteristics, including radiation therapy, did not significantly differ between groups. CAB was associated with a greater mean number of lymphatics bypassed per vein (standard 1.7 vs. CAB 2.6, p = 0.0001) and bypass to larger veins (standard 1.2 vs. CAB 2.2 mm, p < 0.0001). At a median follow-up of 14.7 months, 9.1% (1/11) of individuals receiving CAB developed lymphedema. These rates were similar to those seen following standard bypass at 4.8% (1/21), although within a significantly shorter follow-up duration (standard 7.8 vs. CAB 14.7 months, p = 0.0170). CONCLUSION: The CAB technique is a viable, effective technical alternative to the standard LVB technique. This comparative study of techniques in prophylactic LVB suggests that CABs maintain long-term patency, possibly due to the ease of anastomosing several lymphatics to single large caliber veins while reducing the technical demands of the procedure.
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BACKGROUND: Free tissue transfer (FTT) provides a versatile method to achieve successful lower limb salvage. Thrombocytosis in patients undergoing lower extremity (LE) FTT is associated with increased risk of complications. The aims of this study were to assess the feasibility of performing LE FTT in patients with preoperative thrombocytosis, and whether antiplatelet (AP) therapy on the day of surgery (DOS) affects outcomes. METHODS: A retrospective review of thrombocytotic patients who underwent LE FTT between 2011 and 2022 was performed. Patients were stratified into groups based on the receipt of AP therapy on the DOS. Patients were propensity score matched for comorbidity burden and postoperative risk stratification. Outcomes of interest included perioperative transfusion requirements, postoperative flap-related complications, rates of flap success, limb salvage, and ambulatory status. RESULTS: Of the 279 patients who underwent LE FTT, 65 (23.3%) were found to have preoperative thrombocytosis. Fifty-three patients remained following propensity score matching; of which, 32 (60.4%) received AP therapy on the DOS and 21 (39.6%) did not. Overall flap success rate was 96.2% (n = 51). The likelihoods of thrombosis and hematoma development were similar between cohorts (p = 0.949 and 0.574, respectively). Receipt of DOS AP therapy was associated an additional 2.77 units and 990.10 mL of transfused blood (p = 0.020 and 0.018, respectively). At a mean follow-up of 20.7 months, overall limb salvage and ambulatory rates were 81.1% (n = 43) and 79.2% (n = 42), respectively, with no differences between cohorts. CONCLUSION: Preoperative thrombocytosis is not an absolute contraindication to LE FTT. DOS AP therapy may be protective in comorbid patients with elevated platelet counts but must be weighed against possible short-term bleeding as suggested by significant increases in postoperative transfusion requirements.
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Retalhos de Tecido Biológico , Trombocitose , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Pontuação de Propensão , Resultado do Tratamento , Extremidade Inferior/cirurgia , Estudos Retrospectivos , Complicações Pós-OperatóriasRESUMO
BACKGROUND: In 2021, the US Food and Drug Administration (FDA) issued a new checklist, labeling and rupture screening recommendations for breast implants to improve the decision-making process. OBJECTIVES: This study aims to understand the plastic surgeon's perspective on these changes and their perceived impact on clinical practice. METHODS: In September 2023, a 27 multiple-choice cross-sectional survey was distributed to 4,352 active members of the American Society of Plastic Surgeons to evaluate attitudes on the FDA's black box warning, informed decision checklist, and updated rupture screening recommendations. RESULTS: A total of 591 responses were collected (13.6%). The majority of respondents were between the ages of 45 to 64 (58%) and had been in practice for more than 20 years (52%). Surgeons felt like some additions were appropriate, however the majority (57%) stated that the informed decision checklist did not have a positive impact on workflow; 66% were also neutral or disagreed with the reported incidence rates related to complications and cancer. Nearly half of respondents (47%) did not feel the black box warning improved their patients' understanding of the risks and benefits. Additionally, 47% of respondents also believed these requirements, in combination, did not improve the overall patient experience with implants. CONCLUSIONS: Respondents had an overall positive response towards the addition of risk information provided by the FDA issued guidance and updates to rupture screening recommendations. However, they remain divided as to whether the black box warning and patient decision checklist had an overall positive impact on clinical practice patterns.
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BACKGROUND: Free tissue transfer (FTT) is critical for limb salvage of chronic lower extremity (LE) wounds. In patients with peripheral arterial disease (PAD), FTT LE reconstruction can be challenging due to limited vessel selection for anastomosis. The study aims to evaluate our surgical and functional outcomes after FTT to LE in patients with PAD. METHODS: A retrospective review identified patients who underwent LE free flap reconstruction between 2011 and 2021. All patients underwent preoperative arteriogram and subsequent FTT. Patients were classified into PAD or non-PAD cohorts, based on the presence of LE arterial stenoses or occlusions identified on arteriogram. Primary outcomes included complications, flap success, need for post-FTT vascular reintervention, limb salvage, and ambulatory status. RESULTS: A total of 253 patients underwent FTT to LE, with 84 patients (33.2%) in the PAD cohort. Patients with PAD had a higher prevalence of diabetes (83.3% vs 39.1%, P < 0.001) and end-stage renal disease (8.3% vs 2.4%, P = 0.028). Osteomyelitis was more common in the PAD group (73.8% vs 55.0%, P = 0.004). Free tissue transfer donor sites and flap composition were similar between cohorts. At a mean follow-up of 21.1 months, limb salvage rates were similar between non-PAD and PAD cohorts (90.5% vs 84.5%, P = 0.158), with no significant differences in ambulatory status or mortality. Higher complication rates occurred in the PAD cohort (38.1% vs 20.7%, P = 0.003), of which partial flap necrosis was more prevalent in the PAD group (6.0% vs 0.6%, P = 0.016). There was no difference in flap success rates between groups (P = 0.430). More postflap angiograms were performed in the PAD group (29.8% vs 7.1%, P < 0.001), with repeat percutaneous endovascular intervention performed in 68.0% of the PAD group versus 33.3% of the non-PAD group (P < 0.001). CONCLUSIONS: This is the largest study to demonstrate excellent long-term limb salvage outcomes in patients with PAD who undergo FTT to LE. Percutaneous endovascular intervention and FTT are effective methods to achieve limb salvage in vasculopathic patients with chronic LE wounds.
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Retalhos de Tecido Biológico , Doença Arterial Periférica , Procedimentos de Cirurgia Plástica , Humanos , Retalhos de Tecido Biológico/irrigação sanguínea , Resultado do Tratamento , Doença Arterial Periférica/cirurgia , Salvamento de Membro/métodos , Extremidade Inferior/cirurgia , Estudos Retrospectivos , Fatores de RiscoRESUMO
OBJECTIVE: Chronic lower extremity (LE) wounds are common in patients with peripheral vascular disease (PVD). Free tissue transfer (FTT) provides healthy soft tissue for wound coverage and additional blood supply to promote wound healing. Given previous studies demonstrate increased complications in LE fasciocutaneous flaps, it was hypothesized that low vascular resistance in muscle flaps may be more advantageous for wound healing in PVD patients. Therefore, this study compared outcomes in PVD patients undergoing LE reconstruction with fasciocutaneous versus muscle free flaps. METHODS: Retrospectively reviewed PVD patients undergoing FTT between 2011 and 2021. Patients were stratified into fasciocutaneous and muscle free flap groups. Primary outcomes included complications, flap success, post-reconstruction vascular interventions, limb salvage, and ambulatory status. RESULTS: One hundred thirteen patients with PVD were identified, of which 60.2% received fasciocutaneous (n = 68) and 39.8% received muscle flaps (n = 45). Forty-two patients (37.2%) underwent pre-flap endovascular interventions. Flap success rate was 98.2% (n = 111). Overall complication rate was 41.2% following fasciocutaneous flaps compared to 24.4% in muscle flaps (p = 0.067). Fasciocutaneous flaps had higher odds of ulceration requiring repeat angiogram within 1 year of reconstruction compared to muscle flaps (OR 3.4, 95% CI: 1.07-10.95, p = 0.047), and higher odds of requiring repeat angiogram overall (OR 3.4, 95% CI: 1.07-10.95, p = 0.047). No difference in requiring procedures in the operated limb within 1 year was observed (p = 0.155). At mean follow-up, there was no difference in limb salvage, ambulatory, and mortality rate between groups. CONCLUSION: This study demonstrates that fasciocutaneous flaps had higher postoperative complication rates and more commonly required repeat arteriograms following LE FTT reconstruction due to recurrent ulcerations, suggesting greater utility of muscle flaps for FTT reconstruction in PVD patients.
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Retalhos de Tecido Biológico , Traumatismos da Perna , Doenças Vasculares Periféricas , Procedimentos de Cirurgia Plástica , Humanos , Retalhos de Tecido Biológico/irrigação sanguínea , Estudos Retrospectivos , Salvamento de Membro/métodos , Resultado do TratamentoRESUMO
BACKGROUND: Free tissue transfer (FTT) reconstruction is associated with a high rate of limb salvage in patients with chronic lower extremity (LE) wounds. Studies have shown perioperative risk stratification tools (e.g., 5-factor modified frailty index [mFI-5] and Charlson comorbidity index [CCI]) to be useful in predicting adverse outcomes; however, no studies have compared them in patients undergoing LE reconstruction. The aim of this study is to compare the utility of mFI-5 and CCI in predicting postoperative morbidity in elderly patients receiving LE FTT reconstruction. METHODS: A retrospective review of patients aged 60 years or older who underwent LE FTT reconstruction from 2011 to 2022 was performed. Comorbidity burden was measured by two validated risk-stratification tools: mFI-5 and CCI. Primary outcomes included prolonged postoperative length of stay (LOS), defined as greater than 75th percentile of the cohort, postoperative complications, and eventual amputation. RESULTS: A total of 115 patients were identified. Median CCI and mFI-5 were 5 (interquartile range [IQR]: 4-6) and 2 (IQR: 1-3), respectively. Average postoperative LOS was 16.4 days. Twenty-nine patients (25.2%) experienced a postoperative complication, and eight patients (7%) required LE amputation at a mean follow-up of 19.8 months. Overall, flap success was 96.5% (n = 111), and limb salvage rate was 93% (n = 108). Increased CCI was found to be independently predictive of only eventual amputation (odds ratio: 1.59; p = 0.039), while mFI-5 was not predictive of prolonged postoperative LOS, flap complications, or eventual amputation. CONCLUSION: This is the first study to compare the utility of mFI-5 and CCI in predicting adverse outcomes in elderly patients undergoing LE FTT reconstruction. Our results demonstrate CCI to be a superior predictor of secondary amputation in this patient population and mFI-5 to have limited utility. Further investigation in a prospective multicenter cohort is warranted.
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Fragilidade , Idoso , Humanos , Fragilidade/complicações , Fragilidade/epidemiologia , Fragilidade/cirurgia , Estudos Prospectivos , Tempo de Internação , Comorbidade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Medição de Risco , Fatores de RiscoRESUMO
BACKGROUND: Eyelid surgeries are common operations performed for both cosmetic and functional purposes. Because the periorbital region is highly visible, it is important to avoid poor scar formation in this cosmetically sensitive region. No study to date has investigated the possible existence of keloid formation following eyelid procedures. OBJECTIVES: This study systematically reviewed the literature to identify cases of hypertrophic scar and keloid formation following cosmetic or functional (nonburn) eyelid procedures to aid surgeons when counseling patients. METHODS: A PubMed/MEDLINE search was conducted on May 17, 2022, using appropriate search terms: "blepharoplasty," "tarsorrhaphy," "canthotomy," "ptosis repair," "epicanthoplasty," "keloid," "hypertrophic scar," and related lay terms. All eligible articles in English with no lower date limit were included for analysis. Descriptive statistics, exclusion criteria, and summarized results are reported. RESULTS: The PubMed search yielded 107 abstracts/articles. Full-text review resulted in 34 articles included for analysis. Twenty manuscripts reported no occurrences of hypertrophic scars. Only 13 manuscripts reported patients with hypertrophic scarring, which equated to 36 patients out of 3650. One individual was identified in a series of 77 patients who developed a keloid after a tarsorrhaphy. No articles reported a keloid as an outcome of strictly cosmetic procedures. CONCLUSIONS: This study concludes that there are no reported instances of keloid formation following cosmetic (nonburn) eyelid procedures in the existing literature. Hypertrophic scar formation is minimally reported. The absence of keloid scar formation on the eyelid is critical knowledge for surgeons when educating patients about maladaptive scarring risks following eyelid procedures.
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Blefaroplastia , Cicatriz Hipertrófica , Queloide , Humanos , Cicatriz Hipertrófica/etiologia , Queloide/etiologia , Queloide/cirurgia , Pálpebras/patologia , Blefaroplastia/efeitos adversosRESUMO
BACKGROUND: Free tissue transfer (FTT) lower limb salvage requires costly multidisciplinary care. Traditionally, patients who undergo FTT reconstruction for lower extremity (LE) wounds were admitted to the intensive care unit (ICU) in the immediate postoperative period for close monitoring. During the COVID-19 pandemic, our practice shifted toward admitting FTT patients to the floor postoperatively instead of the ICU. The purpose of this study is to compare surgical outcomes in patients admitted to the floor versus ICU immediately following LE free flap reconstruction. METHODS: We retrospectively reviewed patients undergoing LE FTT reconstruction from 2011 to 2021. Flap monitoring consisted of an implantable Cook-Swartz Doppler probe for muscle flaps and ViOptix tissue oximetry for fasciocutaneous flaps; clinical exam and hand-held dopplers were not the primary flap monitoring techniques. Patients were divided into two groups depending on whether they went to the ICU or floor postoperatively. To ensure proper comparability between cohorts, we corrected for age, BMI and Charlson Comorbidity Index (CCI) using 1:2 propensity score matching (floor: ICU). Primary outcomes included early postoperative complications, flap takeback and salvage, flap success, and postoperative length of stay (LOS). RESULTS: A total of 252 patients were identified. Forty-five patients (17.9%) were admitted to the floor postoperatively and 207 patients (82.1%) to the ICU. Overall, microsurgical success rate was 97.2%, which was similar for floor and ICU patients. Flap takeback and salvage were similar between cohorts. Average postoperative LOS was significantly shorter in floor patients (15.7 vs. 19.1 days, p = 0.043). CONCLUSION: Our findings suggest that postoperative floor admission does not decrease flap success rates and should be considered in patients who undergo FTT to LE reconstruction and are otherwise stable. In the ongoing era of health care cost containment, microsurgery centers should consider appropriate floor training to allow medically stable free flap patients to avoid an ICU stay.
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COVID-19 , Retalhos de Tecido Biológico , Traumatismos da Perna , Procedimentos de Cirurgia Plástica , Retalhos de Tecido Biológico/cirurgia , Humanos , Unidades de Terapia Intensiva , Traumatismos da Perna/cirurgia , Pandemias , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
AIM: The aim of the present study was to compare and evaluate the efficacy of two minimally invasive methods in the removal of infected carious dentin in primary molars. MATERIALS AND METHODS: Eighty primary molars with class I occlusal caries involving dentin were selected and allocated to either of the two groups using convenient sampling. Group A (n = 40) caries were excavated using BRIX 3000 and in Group B (n = 40) atraumatic restorative treatment (ART) caries were excavated using hand instruments only. In both groups, caries removal efficacy was evaluated clinically using caries detection dye (Sable and Sleek), and the patient's discomfort level was noted using the Wong-Baker faces pain rating scale (WBFPS). RESULTS: The results indicated that BRIX 3000 was effective in the removal of caries from primary molars with a significant difference. While there was no statistically significant difference seen in pain perception on caries excavation using both the methods. Although, a mild discomfort was noted in Group B. CONCLUSION: Comparing the two minimally invasive techniques, the new chemomechanical solution (BRIX 3000) was an effective method for the removal of caries from primary molars. So, it can be considered an alternative to the conventional caries removal method in treating pediatric dental patients. CLINICAL SIGNIFICANCE: BRIX 3000 gel is effective in the removal of caries in children who are anxious and apprehensive as it is a noninvasive method of treatment in the pediatric age group.
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Tratamento Dentário Restaurador sem Trauma , Cárie Dentária , Criança , Assistência Odontológica , Cárie Dentária/terapia , Suscetibilidade à Cárie Dentária , Preparo da Cavidade Dentária/métodos , Dentina , Humanos , Dente MolarRESUMO
α-Amylase is the most significant glycoside hydrolase having applications in various industries. It cleaves the α,1-4 glucosidic linkages of polysaccharides like starch, glycogen to yield a small polymer of glucose in α-anomeric configuration. α-Amylase is produced by all the three domains of life but microorganisms are preferred sources for industrial-scale production due to several advantages. Enormous studies and research have been done in this field in the past few decades. Still, it is requisite to work on enzyme stability and catalysis, as it loses its functionality in extreme. As the enzyme loses its structural and catalytic property under extreme environmental conditions, it is mandatory to confer some potential strategies for enhancing enzyme behaviour in such conditions. This limitation of an enzyme can be overcome up to some extent by extremophiles. They serve as an excellent source of α-amylase with outstanding features. This review is an attempt to encapsulate some structure-based strategies for improving enzyme behaviour thereby enabling researchers to selectively amend any of the strategies as per requirement during upstream and downstream processing for higher enzyme yield and stability. Thus, it will provide some cutting-edge strategies for tailoring α-amylase producing organism and enzyme with the help of several computational biology tools.
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Extremófilos , alfa-Amilases , Amilases , Catálise , Biologia ComputacionalRESUMO
We consider a model of an extensible semiflexible filament moving in two dimensions on a motility assay of motor proteins represented explicitly as active harmonic linkers. Their heads bind stochastically to polymer segments within a capture radius, and extend along the filament in a directed fashion before detaching. Both the extension and detachment rates are load-dependent and generate an active drive on the filament. The filament undergoes a first order phase transition from the open chain to spiral conformation and shows a reentrant behavior in both the active extension and the turnover, defined as the ratio of attachment-detachment rates. Associated with the phase transition, the size and shape of the polymer change non-monotonically, and the relevant autocorrelation functions display a double-exponential decay. The corresponding correlation times show a maximum signifying the dominance of spirals. The orientational dynamics captures the rotation of spirals, and its correlation time decays with activity as a power law.
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Citoesqueleto , Polímeros , Cinesinas , Conformação Molecular , Transição de FaseRESUMO
OBJECTIVE: Pathways are succinct, operational versions of evidence-based guidelines. Studies have demonstrated pathways improve quality of care for children hospitalized with asthma, but we have limited information on other key factors to guide hospital leaders and clinicians in pathway implementation efforts. Our objective was to evaluate the adoption, implementation, and reach of inpatient pediatric asthma pathways. METHODS: This was a mixed-methods study of hospitals participating in a national collaborative to implement pathways. Data sources included electronic surveys of implementation leaders and staff, field observations, and chart review of children ages 2-17 years admitted with a primary diagnosis of asthma. Outcomes included adoption by hospitals, pathway implementation factors, and reach of pathways to children hospitalized with asthma. Quantitative data were analyzed using descriptive statistics and multivariable regression. Qualitative data were analyzed using thematic content analysis. RESULTS: Eighty-five hospitals enrolled; 68 (80%) adopted/completed the collaborative. These 68 hospitals implemented pathways with overall high fidelity, implementing a median of 5 of 5 core pathway components (Interquartile Range [IQR] 4-5) in a median of 5 months (IQR 3-9). Implementation teams reported a median time cost of 78 h (IQR: 40-120) for implementation. Implementation leaders reported the values of pathway implementation included improvements in care, enhanced interdisciplinary collaboration, and access to educational resources. Leaders reported barriers in modifying electronic health records (EHRs), and only 63% of children had electronic pathway orders placed. CONCLUSIONS: Hospitals implemented pathways with high fidelity. Barriers in modifying EHRs may have limited the reach of pathways to children hospitalized with asthma.
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Asma/terapia , Procedimentos Clínicos/organização & administração , Fidelidade a Diretrizes/estatística & dados numéricos , Pacientes Internados , Qualidade da Assistência à Saúde/organização & administração , Adolescente , Criança , Pré-Escolar , Procedimentos Clínicos/economia , Procedimentos Clínicos/normas , Registros Eletrônicos de Saúde , Pessoal de Saúde/educação , Humanos , Capacitação em Serviço , Comunicação Interdisciplinar , Guias de Prática Clínica como Assunto , Qualidade da Assistência à Saúde/economia , Qualidade da Assistência à Saúde/normasRESUMO
OBJECTIVE: To examine the relationship between food security status, diet quality measured using Healthy Eating Index-2010 (HEI-2010) scores, demographics and the following factors: perceptions of healthy food availability, healthy eating identity and perceived control of healthy eating. DESIGN: A cross-sectional study in 2016-2017 using three 24-h dietary recalls and one psychosocial survey. SETTING: Two urban communities in Cleveland and Columbus, Ohio, USA, with low access to healthy food retailers. PARTICIPANTS: Primary food shoppers living in the targeted geographic areas (N 450). RESULTS: Our results indicated that high school graduates had lower HEI-2010 scores compared with participants who had some college education or more (ß = -2·77, P = 0·02). Participants receiving Supplemental Nutrition Assistance Program (SNAP) benefits had lower HEI-2010 scores (ß = -2·69, P = 0·03). Healthy eating identity was associated with higher HEI-2010 scores (ß = 1·85, P = 0·004). Food security status moderated the relationship between perception of healthy food availability and HEI-2010 scores. Among participants with very low food security (VLFS), greater perceptions of healthy food availability were associated with higher HEI-2010 scores (ß = 3·25, P = 0·03), compared with food secure participants. Only 14 % of VLFS participants used a personal vehicle as transportation to their primary food shopping store. CONCLUSIONS: Findings offer targets for future intervention development and evaluation to promote community nutrition. These targets include strategies to improve the value of SNAP benefits, promote access to quality education, increase transportation options to healthy food retailers and develop nutrition programming to promote healthy eating identity.
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Assistência Alimentar , Segurança Alimentar , Adulto , Estudos Transversais , Dieta , Abastecimento de Alimentos , Humanos , PobrezaRESUMO
The Heat shock proteins 90 family plays pivotal roles in root growth and plant development. Its isoforms have been identified in several plant species with transcripts presents in almost all stages of plant growth. However, its functional relevance has not been completely established. Therefore, in this study, we provide evidence about the role of SlHSP90.2 in tomato (Solanum lycopersicum) root development. Using tomato cultivars with differing root phenotypes, we have shown that SlHSP90.2 transcripts are in accordance with root architecture, i.e. high rooting cultivars had more expression of SlHSP90.2 as compared to low rooting cultivars. Moreover, overexpression of SlHSP90.2 gene in transgenic tomato plants showed significant increase in root biomass and architecture, as evident from the analysis of fresh and dry weights of root and shoot samples, primary root length and length and number of lateral roots. The transgenic lines are also more tolerant to salinity and drought stresses. The results of the present study suggest that genetic manipulation of HSP90.2 homologs in other crops can offer promising leads to develop plant with better root biomass and architecture and improved agronomics traits, like better water and mineral absorption, salinity and drought tolerance potential.
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Arabidopsis MYC2 bHLH transcription factor plays a negative regulatory role in blue light (BL)-mediated seedling development. HY5 bZIP protein works as a positive regulator of multiple wavelengths of light and promotes photomorphogenesis. Both MYC2 and HY5, belonging to two different classes of transcription factors, are the integrators of multiple signaling pathways. However, the functional interrelations of these two transcription factors in seedling development remain unknown. Additionally, whereas HY5-mediated regulation of gene expression has been investigated in detail, the transcriptional regulation of HY5 itself is yet to be understood. Here, we show that HY5 and MYC2 work in an antagonistic manner in Arabidopsis seedling development. Our results reveal that HY5 expression is negatively regulated by MYC2 predominantly in BL, and at various stages of development. On the other hand, HY5 negatively regulates the expression of MYC2 at various wavelengths of light. In vitro and in vivo DNA-protein interaction studies suggest that MYC2 binds to the E-box cis-acting element of HY5 promoter. Collectively, this study demonstrates a coordinated regulation of MYC2 and HY5 in blue-light-mediated Arabidopsis seedling development.
Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Plântula/genética , Antocianinas/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Gravitropismo/genética , Luz , Microscopia de Fluorescência , Mutação , Fenótipo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/efeitos da radiação , Técnicas do Sistema de Duplo-HíbridoRESUMO
DNA sequencing of the SERPINA1 gene to detect α1-antitrypsin (AAT) deficiency (AATD) may provide a better appreciation of the individual and cumulative impact of genetic variants on AAT serum levels and COPD phenotypes.AAT serum level and DNA sequencing of the coding regions of SERPINA1 were performed in 1359 participants of the Canadian Cohort Obstructive Lung Disease (CanCOLD) study. Clinical assessment for COPD included questionnaires, pulmonary function testing and computed tomography (CT) imaging. Phenotypes were tested for association with SERPINA1 genotypes collated into four groups: normal (MM), mild (MS and MI), intermediate (heterozygote MZ, non-S/non-Z/non-I, compound IS, and homozygote SS) and severe (ZZ and SZ) deficiency. Smoking strata and MZ-only analyses were also performed.34 genetic variants were identified including 25 missense mutations. Overall, 8.1% of alleles in this Canadian cohort were deficient and 15.5% of 1359 individuals were carriers of at least one deficient allele. Four AATD subjects were identified and had statistically lower diffusion capacity and greater CT-based emphysema. No COPD phenotypes were associated with mild and intermediate AATD in the overall cohort or stratified by smoking status. MZ heterozygotes had similar CT-based emphysema, but lowered diffusion capacity compared with normal and mild deficiency.In this Canadian population-based cohort, comprehensive genetic testing for AATD reveals a variety of deficient alleles affecting 15.5% of subjects. COPD phenotype was demonstrated in severe deficiency and MZ heterozygotes. This study shows the feasibility of implementing a diagnostic test for AATD using DNA sequencing in a large cohort.
Assuntos
Doença Pulmonar Obstrutiva Crônica , Deficiência de alfa 1-Antitripsina , Alelos , Canadá , Genótipo , Humanos , Doença Pulmonar Obstrutiva Crônica/genética , Análise de Sequência de DNA , alfa 1-Antitripsina/genética , Deficiência de alfa 1-Antitripsina/diagnóstico , Deficiência de alfa 1-Antitripsina/genéticaRESUMO
BACKGROUND: Chlorhexidine (CHX) is a widely utilized disinfectant that can cause IgE-mediated urticaria/anaphylaxis. The cross-reactivity of patients with IgE-mediated CHX allergy with other disinfectants, which share structural similarities with CHX like polyhexanide (polyhexamethylene biguanide; PHMB), alexidine (ALX), or octenidine (OCT), is unknown. METHODS: Forty-four patients with anaphylaxis or urticaria upon CHX exposure and positive skin prick test (SPT) and/or positive CHX ImmunoCAP test (Phadia TFS, Uppsala, Sweden) were recruited. IgE to the biguanide and/or hexamethylene structure was investigated with PHMB ImmunoCAP (n = 32) and by basophil activation tests (BAT) with CHX and ALX (n = 37). Inhibition tests of CHX and PHMB ImmunoCAPs by CHX, ALX, PHMB, and OCT were performed. RESULTS: IgE reactivity to PHMB as surrogate marker for biguanide/hexamethylene reactivity was detected in 5/32 sera. Seven of 37 patients showed a positive BAT with ALX, but only under optimized conditions. Binding to CHX ImmunoCAP was inhibited by ALX in 1/32 sera, and binding to PHMB was blocked by ALX (1/5) and by OCT in another (1/5). In SPT, 9/10 patients were positive for CHX and 3 of them with ALX (only at highest concentration at 5 mg/mL). A further patient reacted primarily with OCT and showed IgE cross-reactivity with CHX, ALX, and PHMB. CONCLUSION: The IgE response to CHX seems polyclonal. The chloroguanide ending of CHX is the main epitope for the IgE and is suitable as screening assay to detect CHX reactivity. IgE-reactivities with the biguanide or hexamethylene components of other disinfectants (ALX, PHMB) can be detected by SPT, PHMB ImmunoCAP, and ALX-BAT in 15%-33% of CHX-allergic patients.