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1.
Mol Biol Rep ; 49(6): 5511-5520, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35484441

RESUMEN

BACKGROUND: Onion is an economically important vegetable cultivated worldwide on a large scale. Liberal exchange of germplasm and frequent selection caused narrow genetic diversity in most crops, including onion. Thus, it is essential to estimate and understand genetic diversity before launching of any breeding program. The current study was conducted to explore genetic diversity among 39 short-day onion genotypes (indigenous and exotic). METHODS AND RESULTS: All the genotypes were evaluated for various phenotypic traits by using single nucleotide polymorphism (SNP) genotyping based on KASPar assays. Principal component analysis (PCA) was performed to determine the variability among genotypes. The four principal components with eigenvalue greater than 1 accounted for 67.5656% variability for quantitative traits, whereas first five principal components with eigenvalue greater than 0.7 accounted for 86.24% variation among the genotypes for qualitative traits. The principal component analysis identified diverse traits including bulb weight, bulb diameter, plant height, number of survived plants and vitamin C. These traits were further analyzed through ANOVA (Analysis of Variance) following augmented block design to describe genotypic variability for selected traits. Onion genotypes showed significant variation for bulb weight, bulb diameter and Vitamin C. Genotypic clustering based on PCA showed that 15 indigenous genotypes were clustered with exotic genotypes (14) while remaining indigenous genotypes (10) were distant. A total of 30 SNPs were used for assessment of genetic diversity out of these, 24 SNPs were detected with polymorphic loci (0.8%, heterozygosity), while only six markers were with monomorphic sites (0.2% heterozygosity). Subsequently, population structure analysis revealed three different populations indicating significant variability. CONCLUSION: Conclusively, a significant similarity between exotic and a group of indigenous genotypes indicates direct adoption of exotic genotypes or their sister lines. A further broadening of the genetic base is required and could be done by crossing distant genotypes.


Asunto(s)
Cebollas , Polimorfismo de Nucleótido Simple , Ácido Ascórbico , Variación Genética/genética , Genotipo , Cebollas/genética , Fitomejoramiento , Polimorfismo de Nucleótido Simple/genética
2.
Pak J Pharm Sci ; 30(1 Suppl): 335-340, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28625963

RESUMEN

Metallo-ß-lactamases (MBLs) are zinc ion dependent enzymes that are responsible for the emergence and spread of ß-lactam resistance among bacterial pathogens. There are uncharacterized putative MBLs in the environment and their emergence is major interference in the generation of universal MBL inhibitors so it is important to identify and characterize novel MBLs. In this study two novel MBLs from Luteimonas sp. J29 and Pseudoxanthomonas mexicana were identified using B3 MBLs as query in BLAST database search. 3D models of putative MBLs generated by SWISS-MODEL server taking AIM-1 as a structural template were verified using web based structure assessment and validation programs. Multiple sequence alignment revealed that residues important for substrate binding were conserved and loop region residues (156-162 and 223-230) important for catalysis are variable in these novel MBLs. Homology models showed typical MBL α/ß/ß/α sandwich fold containing six α helices, twelve ß strands and metal interacting residues are conserved in similar way as with other B3 MBLs. We report promising putative B3 MBLs with some variations and substrate docking studies revealed that novel MBLs have attributes close to acquired B3 MBLs.


Asunto(s)
beta-Lactamasas/metabolismo , Secuencia de Aminoácidos , Dominio Catalítico/fisiología , Alineación de Secuencia , Especificidad por Sustrato/fisiología , Zinc/metabolismo , beta-Lactamas/metabolismo
3.
Urol Case Rep ; 52: 102598, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38143723

RESUMEN

Inflammatory myofibroblastic tumors of the bladder (IMTB) are rare neoplasms that can occur in children. These tumors have uncertain malignant potential and can present similarly to bladder sarcomas. It is important to differentiate between IMTB and bladder sarcomas using a careful immunohistochemical approach. We report a case of IMTB in a 12-year-old girl who presented with presyncope and gross hematuria. IMTB was diagnosed through immunohistochemical analysis, and clinical improvement was observed after resection of the tumor.

4.
Cureus ; 15(4): e37701, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37206503

RESUMEN

Mediastinal hematomas are thoracic complications often resulting from direct trauma or aortic dissections. Spontaneous non-traumatic mediastinal hematomas are rare. We present a case of spontaneous non-traumatic mediastinal hematoma in a patient on Imatinib therapy for a gastrointestinal stromal tumor (GIST). A 67-year-old female presented to the ER with the chief complaint of constant sharp right shoulder pain that progressed to her chest. The patient was not on any anticoagulants and had not complained of shortness of breath. Under suspicion of a pulmonary embolism, a CT chest scan was performed, and a diagnosis of non-traumatic anterior mediastinal hematoma was confirmed. This case may warrant further investigation into the links between Imatinib use and the formation of mediastinal hematomas.

5.
Cureus ; 15(8): e44218, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37767267

RESUMEN

In the past, surgical treatment of anterior cruciate ligament (ACL) tears has mainly involved reconstruction using allografts and autografts. The relatively new FDA-approved bridge-enhanced ACL repair (BEAR) procedure allows the body to use its innate healing properties to help repair the ACL using an absorbable protein-based implant. The procedure is currently being offered by surgeons in 44 states. This case describes the first BEAR procedure performed in the state of Mississippi. A 47-year-old female of normal BMI presented to the orthopedic clinic with a chief complaint of right knee pain. The patient stated that she felt unstable on the injured knee, and the patient had positive anterior drawer and Lachman's tests on physical examination. MRI of the knee one month after injury revealed full-thickness ACL rupture. The patient underwent arthroscopic bridge-enhanced ACL repair in the right knee 43 days after the initial injury. The patient reported positive progress in her healing process at her three-month follow-up, and MRI at the three-month follow-up showed successful repair of the patient's ACL. At six months post-operatively, the patient reported that she is still doing well, and she feels that the stability of her right knee has improved. This case highlights an early trend towards repairs instead of reconstructions in ACL injuries for candidates that meet the following requirements: within 50 days of injury and have an intact tibial stump as recommended by the implant manufacturers.

6.
Front Plant Sci ; 14: 1265700, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38023925

RESUMEN

This study aimed to investigate the impact of individual drought, heat, and combined drought and heat stress on twelve cotton genotypes, including eight tolerant and four susceptible genotypes. A field experiment was carried out by employing a randomized complete block split-plot design, with treatments (control, drought, heat, drought + heat), and cotton genotypes assigned to the main plots and sub-plots respectively. The results showed that the combined stress had a more severe impact on the yield and fiber quality of cotton genotypes compared to individual stresses. Among the studied genotypes, FB-Shaheen, FH-207, MNH-886, and White Gold exhibited superior performance in regard to agronomic and fiber quality characters under combined stress environments. Physiological parameters, including transpiration rate, stomatal conductance, relative water contents, and photosynthetic rate, were significantly reduced under combined stress. However, specific genotypes, MNH-886, FH-207, White Gold, and FB-Shaheen, demonstrated better maintenance of these parameters, indicating their enhanced tolerance to the combined stress. Furthermore, the accumulation of reactive oxygen species was more pronounced under combined stress compared to individual stressors. Tolerant genotypes showed lower levels of H2O2 and MDA accumulation, while susceptible genotypes exhibited higher levels of oxidative damage. Antioxidant enzyme activities, such as superoxide dismutase, peroxidase, and catalase, increased under combined stress, with tolerant genotypes displaying higher enzyme activities. Conversely, susceptible genotypes (AA-703, KZ 191, IR-6, and S-15) demonstrated lower increases in enzymatic activities under combined stress conditions. Biochemical traits, including proline, total phenolic content, flavonoids, and ascorbic acid, exhibited higher levels in resistant genotypes under combined stress, while sensitive genotypes displayed decreased levels of these traits. Additionally, chlorophyll a & b, and carotenoid levels were notably decreased under combined stress, with tolerant genotypes experiencing a lesser decrease compared to susceptible genotypes.

7.
BMJ Case Rep ; 15(6)2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35725277

RESUMEN

Immune thrombocytopenic purpura (ITP) is an autoimmune disorder caused by autoantibodies against platelet antigens resulting in platelet destruction and inhibition of platelet production. Occasionally, an inciting event such as a virus or vaccination can precipitate ITP. Several cases of ITP have been reported after the BTN162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) SARS-CoV-2 (COVID-19) vaccines. All reported cases of post-vaccination ITP have resolved with medical therapy until this case.A man in his mid-20s developed bleeding from ITP 2 weeks after receiving the second dose of the Pfizer SARS-CoV-2 vaccine. All inpatient medical treatment attempts failed. On hospital day 40, a splenectomy was performed and he ultimately recovered and was discharged.Awareness of potential vaccination side effects is a fundamental element of refining and improving patient safety. This case illustrates that given the right circumstances, serious refractory ITP can develop in response to the second dose of the Pfizer SARS-CoV-2 vaccine.


Asunto(s)
Vacuna BNT162 , COVID-19 , Púrpura Trombocitopénica Idiopática , Esplenectomía , Vacuna BNT162/efectos adversos , Humanos , Masculino , Púrpura Trombocitopénica Idiopática/inducido químicamente , Púrpura Trombocitopénica Idiopática/cirugía , SARS-CoV-2
8.
Neoreviews ; 23(9): e603-e612, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-36047752

RESUMEN

Neonatal conjunctivitis is an important cause of ocular morbidity with infectious and noninfectious origins. Common practice in the United States is to administer prophylactic antibiotic ointment at birth; however, prophylaxis is ineffective for some causes. Moreover, recognition of the etiologies that threaten systemic complications to the neonate is critical in providing timely and appropriate treatment. This review summarizes the clinical features, etiology, and treatment recommendations of various forms of neonatal conjunctivitis.


Asunto(s)
Conjuntivitis , Enfermedades del Recién Nacido , Conjuntivitis/diagnóstico , Conjuntivitis/etiología , Conjuntivitis/terapia , Humanos , Recién Nacido , Enfermedades del Recién Nacido/diagnóstico , Enfermedades del Recién Nacido/terapia
9.
Front Genet ; 13: 772517, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35464861

RESUMEN

Spring wheat (Triticum aestivum L.) is one of the most imperative staple food crops, with an annual production of 765 million tons globally to feed ∼40% world population. Genetic diversity in available germplasm is crucial for sustainable wheat improvement to ensure global food security. A diversity panel of 184 Pakistani wheat accessions was genotyped using 123,596 high-quality single nucleotide polymorphism (SNP) markers generated by genotyping-by-sequencing with 42% of the SNPs mapped on B, 36% on A, and 22% on D sub-genomes of wheat. Chromosome 2B contains the most SNPs (9,126), whereas 4D has the least (2,660) markers. The mean polymorphic information content, genetic diversity, and major allele frequency of the population were 0.157, 0.1844, and 0.87, respectively. Analysis of molecular variance revealed a higher genetic diversity (80%) within the sub-population than among the sub-populations (20%). The genome-wide linkage disequilibrium was 0.34 Mbp for the whole wheat genome. Among the three subgenomes, A has the highest LD decay value (0.29 Mbp), followed by B (0.2 Mbp) and D (0.07 Mbp) genomes, respectively. The results of population structure, principal coordinate analysis, phylogenetic tree, and kinship analysis also divided the whole population into three clusters comprising 31, 33, and 120 accessions in group 1, group 2, and group 3, respectively. All groups were dominated by the local wheat accessions. Estimation of genetic diversity will be a baseline for the selection of breeding parents for mutations and the genome-wide association and marker-assisted selection studies.

10.
J Surg Res ; 171(1): 170-4, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20605592

RESUMEN

BACKGROUND: Pulmonary artery (PA)-left atrial (LA) shunt models in piglets have been described, but technical details critical to limit morbidity/mortality and promote study of chronic cyanosis are lacking. Accordingly, we describe our experience with an optimized technique. MATERIALS AND METHODS: In 25 6- to 8-wk-old Yorkshire piglets, a beveled, 8 mm, polytetrafluoroethylene tube graft was anastomosed to the PA and LA. Systemic pressure was maintained at >60 mmHg. Saturation targets were met by adjusting a Teflon band on the graft and distal PA. The target oxygen saturation (SO(2)) was 85% on a 50% fraction of inspired oxygen (FiO(2)). If the SO(2) was <75% on a 50% FiO(2), the graft was constricted to achieve a SO(2) ≥ 90% on a 100% FiO(2) and 75%-80% on a 21% FiO(2). Complications affecting mortality were neutralized with a stepwise strategy to minimize risk. RESULTS: Thrombosis, blood loss, and arrhythmia were determinants of survival. Protocol optimization over time increased survival while assuring chronic cyanosis. Survival approached 90%, with a SO(2) of 80% to 90%, 3 to 5 wk postoperatively. Complications included bleeding, excessive hypoxemia, uncontrolled shunt flow, arrhythmias, and thrombosis. CONCLUSIONS: Refinement of surgical technique, shunt adjustment via graft banding, and thrombotic and arrhythmia prophylaxis are the keys to success with this model.


Asunto(s)
Cianosis/patología , Modelos Animales de Enfermedad , Cardiopatías Congénitas/patología , Sus scrofa , Anastomosis Quirúrgica , Animales , Arritmias Cardíacas/mortalidad , Arritmias Cardíacas/patología , Materiales Biocompatibles , Enfermedad Crónica , Cianosis/mortalidad , Atrios Cardíacos/patología , Cardiopatías Congénitas/mortalidad , Hipoxia/patología , Politetrafluoroetileno , Arteria Pulmonar/patología , Trombosis/patología
11.
Cureus ; 13(7): e16564, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34430166

RESUMEN

Background Breastfeeding plays a vital role in a newborn's life as it increases its chances of survival and is considered the optimal nutritional source for newborns. All newborns must have developed the suck, swallow, and breathe coordination in order to safely breastfeed. Studies conducted on breastfeeding in healthy term babies are limited as most studies available on breastfeeding focus on preterm babies. Full-term healthy infants can also present with feeding difficulties but due to a lack of studies conducted on them, there is no existing oxygen saturation pattern for healthy term infants. Thus, our study is designed to observe variations in the oxygen saturation of healthy term infants during breastfeeding. Methodology A cross-sectional study was conducted in a tertiary care hospital from March 2021 to April 2021. Using a non-probability consecutive sampling technique, 60 neonates were enrolled in the study. The baby was monitored for heart rate and oxygen saturation before, during, and after feeding. Results The oxygen saturation levels were lower during feed while it was significantly high after a feed (p < 0.001). No significant variation was seen between saturation before feeding and during feed (0.635) or before feeding with after feed (p = 0.108). Maximum oxygen saturation drop was observed in 21% at the first minute and cumulatively 73% of neonates within the first five minutes of feeding. Heart rate remained in the physiological range (120-160 b/min) in 85%, above 160 in just 11.6% of the babies. Conclusion Effective breastfeeding is crucial for the growth and development of every infant, which is why there is a need to have an understanding of how infants develop suck, swallow, and breathe coordination. Having breathing and sucking patterns for infants can help medical personal identify when an infant is having difficulty with oral feeding and suggest safer, more effective methods of breastfeeding.

12.
Cureus ; 13(9): e17711, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34650885

RESUMEN

OBJECTIVE: Extubation failure is common in mechanically ventilated neonates. Finding objective criteria for predicting successful extubation may help to reduce the incidence of failure and the length of mechanical ventilation (MV). We conducted this study to determine the accuracy of the spontaneous breathing trial (SBT) and lung function measurements in predicting successful extubation in neonates. METHODOLOGY: This cross-sectional validation study was conducted at a tertiary care neonatal intensive care unit (NICU) over 12 months from December 2019 to December 2020. Neonates intubated for >24 hours and considered ready for extubation were enrolled in the study. Neonates who met defined eligibility criteria underwent a three minutes SBT using endotracheal continuous positive airway pressure (ET-CPAP) before extubation. The primary clinical team was blinded to the results, and all neonates were extubated after SBT. Extubation was considered successful if patients remained extubated for 48 hours. RESULTS: Among the 107 infants, 77.5% (n=83) of infants passed the SBT. Of these, 78 were successfully extubated, giving the positive predictive value of 93.97%. The overall extubation success rate was 90% (n=96). The sensitivity and specificity of SBT were 81.2% and 54.5%, respectively. VE (ET-CPAP) and VE-ventilator at a cutoff of ≥238 ml and ≥143.7 ml have an area under the curve (AUC) of 0.77 and 0.75 respectively to predict successful extubation (p-value 0.003, 0.008 respectively). CONCLUSION: SBT predicts extubation success with pronounced accuracy. Therefore, we propose SBT as a valuable and crucial step that guides clinicians' decision-making regarding extubation preparedness or impending failure in neonates.

13.
South Med J ; 103(6): 567-9, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20710143

RESUMEN

Spigelian hernia is a rare abdominal wall defect usually appearing between the abdominal muscle lateral to the rectus abdominis and through a debilitated spigelian aponeurosis. Spigelian hernias account for 0.12% to 2.4% of all abdominal wall hernias with a 17-24% risk of strangulation. We report the case of a 77-year-old male that presented with small bowel obstruction with incarcerated spigelian hernia which was successfully treated with a Ventralex hernia patch (Bard Access Systems, Inc., Murray Hill, NJ). A small open incision over the incarcerated hernia was a safe and effective method of repairing an incarcerated spigelian hernia in an urgent fashion.


Asunto(s)
Hernia Ventral/complicaciones , Hernia Ventral/diagnóstico , Obstrucción Intestinal/diagnóstico , Obstrucción Intestinal/etiología , Intestino Delgado , Anciano , Hernia Ventral/cirugía , Humanos , Obstrucción Intestinal/cirugía , Intestino Delgado/cirugía , Masculino , Politetrafluoroetileno , Mallas Quirúrgicas , Técnicas de Sutura , Tomografía Computarizada por Rayos X
14.
South Med J ; 102(1): 94-5, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19077781

RESUMEN

This is a case report of tuberculous peritonitis (TB), an entity which is difficult to diagnose. When TB is found in extrapulmonary organs it is usually associated with an immunocompromised state, such as that caused by the human immunodeficiency virus (HIV). Medical therapy continues to be the treatment of choice and, if the correct diagnosis is made early, surgery is rarely required.


Asunto(s)
Peritonitis Tuberculosa/diagnóstico , Dolor Abdominal/etiología , Adulto , Antituberculosos/uso terapéutico , Infecciones por VIH/microbiología , Humanos , Obstrucción Intestinal/microbiología , Obstrucción Intestinal/cirugía , Laparotomía , Masculino , Peritonitis Tuberculosa/tratamiento farmacológico , Peritonitis Tuberculosa/cirugía , Peritonitis Tuberculosa/virología , Tomografía Computarizada por Rayos X
15.
J Clin Biochem Nutr ; 41(2): 132-8, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18193107

RESUMEN

An intracellular glucose oxidase was isolated from the mycelium extract of a locally isolated strain of Aspergillus niger UAF-1. The enzyme was purified to a yield of 28.43% and specific activity of 135 U mg(-1) through ammonium sulfate precipitation, anion exchange and gel filtration chromatography. The enzyme showed high affinity for D-glucose with a Km value of 2.56 mM. The enzyme exhibited optimum catalytic activity at pH 5.5. Temperature optimum for glucose oxidase, catalyzed D-glucose oxidation was 40 degrees C. The enzyme showed a high thermostability having a half-life 30 min, enthalpy of denaturation 99.66 kJ mol(-1) and free energy of denaturation 103.63 kJ mol(-1). These characteristics suggest the use of glucose oxidase from Aspergillus niger UAF-1 as an analytical reagent and in the design of biosensors for clinical, biochemical and diagnostic assays.

17.
J Pharm Bioallied Sci ; 6(1): 16-21, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24459399

RESUMEN

OBJECTIVE: Efficacy and safety concerns have been raised in the literature with the use of tribromoethanol (TBE) (Avertin(®)) for anesthesia in rats and mice when administered by intraperitoneal (IP) injection. Despite the controversy, it remains in common usage as an anesthetic agent in laboratory rodents for short-term surgical procedures. Cyclodextrins have been shown to improve drug solubility and were investigated here as an improved anesthetic formulation for mice. MATERIALS AND METHODS: The phase solubility of TBE with hydroxypropyl-ß-cyclodextrin (HP-ß-CD) was estimated. The efficacy of two anesthetic regimens was compared in this study; the conventional TBE formulation solubilized in tert-amyl alcohol and a HP-ß-CD formulation containing TBE. Mice (n = 6) were administered the formulations by IP injection and the pharmacodynamic parameters of time to induction of anesthesia, duration of anesthesia and recovery time were measured using a combined reflex score (CRS). RESULTS AND DISCUSSION: Phase solubility studies showed a linear increase in the solubility of TBE with increasing HP-ß-CD concentration and suggested >1:1 binding of the drug in the cyclodextrin complex. At a dose of 260 mg/kg the standard TBE formulation appeared to produce deeper anesthesia than the cyclodextrin formulation, with a minimum average CRS of 1.8 compared with 5.2. No post-mortem pathology was observed in mice that received either the conventional or cyclodextrin formulation. CONCLUSION: The cyclodextrin TBE formulation did not conclusively provide an improved anesthetic response at a dose of 260 mg/kg compared with the conventional formulation. The improved solubility of TBE with HP-ß-CD and the reduced variability in anesthetic response warrants the further investigation of this formulation. This study has also identified the value of using the anticholinergic atropine in association with TBE for anesthesia.

18.
J Coll Physicians Surg Pak ; 22(3): 135-8, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22414350

RESUMEN

OBJECTIVE: To determine the frequency of HPV in eaters of Gutka (betel, areca, lime and tobacco concoction), presenting with oral lesions. STUDY DESIGN: A descriptive study. PLACE AND DURATION OF STUDY: Ziauddin University Research Laboratory, from February to July 2010. METHODOLOGY: Subjects munching Gutka fulfilled the inclusion criteria. Samples were collected in the form of 20 - 40 ml oral rinse from 262 subjects who were habitual eaters of Gutka after an informed consent. Gentle brushings from the lesion were taken from subjects with the help of a brush at the other end of dental floss and the oral rinse was stored at 4°C until DNA extraction. DNA was extracted and PCR was performed using HPV consensus primers Gp5+/Gp6+. Oral cavity was examined for the presence of ulcer, trismus, sub-mucosal fibrosis, leukoplakia and/or warts. RESULTS: Out of 262 subjects, 42 were females and 220 males with an average age of 27± 10 years. HPV was positive in 47 subjects (17.9%). HPV frequency was 2.7% greater in chewers with more than 10 years of habit compared to less than 10 years. Examination of oral cavity showed 78% presenting with more than one complaint including oral ulcers (25%), rough mucosa (62%), sub-mucosal fibrosis (24%), leukoplakia (20%) and erythroplakia (10.6%). Highest frequency of HPV was observed in erythroplakia (25%). Association between presence of symptoms and HPV shows an ODDS RATIO: ad/bc= 4982/430=11.6. CONCLUSION: Oral lesions caused by constant exposure to Gutka are associated with high frequency of HPV infection, which may be a risk factor for squamous cell carcinoma of the oral cavity. People should be educated about the consequences of Gutka abuse.


Asunto(s)
Areca/efectos adversos , Conducta Alimentaria , Enfermedades de la Boca/inducido químicamente , Neoplasias de la Boca/epidemiología , Papillomaviridae/genética , Infecciones por Papillomavirus/epidemiología , Trastornos Relacionados con Sustancias/epidemiología , Acacia/efectos adversos , Adolescente , Adulto , Mezclas Complejas/efectos adversos , ADN Viral/análisis , Femenino , Humanos , Incidencia , Masculino , Enfermedades de la Boca/epidemiología , Enfermedades de la Boca/patología , Mucosa Bucal/efectos de los fármacos , Mucosa Bucal/patología , Neoplasias de la Boca/inducido químicamente , Neoplasias de la Boca/patología , Pakistán/epidemiología , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/virología , Reacción en Cadena de la Polimerasa , Factores de Riesgo , Trastornos Relacionados con Sustancias/etiología , Trastornos Relacionados con Sustancias/patología , Tabaco sin Humo/efectos adversos , Adulto Joven
19.
Tissue Eng Part A ; 15(6): 1281-90, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18928401

RESUMEN

We previously demonstrated the ability to create engineered arteries by carefully controlling the mechanical environment of intact arteries perfused ex vivo, yielding engineered arteries with native appearance and vasoactive response. Increased axial strain was sufficient to increase length up to 20% in 9 days through a growth and remodeling response. The amount of the achievable length increase, however, was highly dependent on the hemodynamic conditions acting through unknown mechanisms. Because matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) activity is increased, and often required, in mechanically induced remodeling in vivo, MMP-2 and MMP-9 expression was investigated to elucidate the hemodynamic mediation of artery length. Carotid arteries from 30 kg pigs were perfused for 9 days ex vivo at either in situ axial strain or with a gradual 50% increase in axial strain, under either arterial or reduced hemodynamics ( approximately 10% of arterial hemodynamics). MMP-2 protein expression increased roughly twofold, while MMP-9 expression increased threefold under either reduced hemodynamics or increased axial strain (p < 0.05). The combination of reduced hemodynamics with increased axial strain demonstrated an additive increase in MMP-9 protein (p < 0.05) with no further change in MMP-2 expression. To investigate the mechanism by which axial strain and hemodynamics could additively increase MMP-9 expression, the expression of nuclear factor kappa B (NF-kappaB) subunits p50 and p65 was evaluated. Axial strain stimulated p65 expression and localization, while hemodynamics increased p50 expression, with both molecules being expressed only when both mechanical stimuli were applied. These data suggest that MMP-9 expression can be simultaneously stimulated by separate mechanical stimuli mediated by p50 and p65 expression, and that by using conditions that maximize MMP-9 expression, we can create an optimal remodeling environment to better direct the growth of engineered arteries and other tissues.


Asunto(s)
Arterias/enzimología , Matriz Extracelular/enzimología , Hemodinámica , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Estrés Mecánico , Ingeniería de Tejidos , Animales , Arterias/citología , Núcleo Celular/metabolismo , Elastina/metabolismo , Inmunohistoquímica , Subunidad p50 de NF-kappa B/metabolismo , Transporte de Proteínas , Sus scrofa , Factor de Transcripción ReIA/metabolismo
20.
J Thorac Cardiovasc Surg ; 138(2): 382-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19619782

RESUMEN

OBJECTIVE: We sought to determine the impact of relieving branch pulmonary artery stenosis on pulmonary valve insufficiency and right ventricular function. Long-standing pulmonary insufficiency causes progressive right ventricular dilatation, leading to decreased right ventricular function. Adults with pulmonary insufficiency are at risk of decreased exercise tolerance, arrhythmias, and sudden cardiac death. Branch pulmonary artery stenosis frequently occurs in these patients, and the presence of branch stenosis may exacerbate valve insufficiency. METHODS: Neonatal piglets (n = 7) underwent surgery to create pulmonary insufficiency and left pulmonary artery stenosis. At 3 months of age, the animals underwent baseline cardiac magnetic resonance imaging followed by stenting of the left pulmonary artery. A repeat magnetic resonance imaging scan was performed 1 week after intervention. Magnetic resonance imaging evaluation included (1) velocity mapping to assess the forward and reverse flow at the main, left and right pulmonary arteries, and aorta; and (2) volumetric assessment of the right ventricle. RESULTS: Left pulmonary artery flow increased from 14.5% to 36.3% of total net flow after stenting (P < .01). Pulmonary regurgitation decreased from 38.7% to 27.4% (P < .02). Right ventricular ejection fraction improved from a median of 53.5% to 58.2% after stenting (P < .01). Cardiac index improved from a median of 2.7 to 3.5 L/min/m(2) (P = .01). CONCLUSION: Relief of branch pulmonary artery stenosis reduces insufficiency and improves right ventricular systolic function in this animal model. This supports the practice of aggressive intervention in patients with branch pulmonary artery stenosis and pulmonary insufficiency.


Asunto(s)
Arteria Pulmonar/cirugía , Insuficiencia de la Válvula Pulmonar/fisiopatología , Animales , Velocidad del Flujo Sanguíneo , Constricción Patológica , Hemodinámica , Imagen por Resonancia Magnética , Imagen por Resonancia Cinemagnética , Miocardio/patología , Arteria Pulmonar/patología , Insuficiencia de la Válvula Pulmonar/cirugía , Sus scrofa , Función Ventricular Derecha
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