Double and Single Bundle in Athletes: A Comparison in Medium and Long-Term Rates to Return to Sport and Re-Injury.

Objectives: Compare, retrospectively, the medium- and long-term of return to sport rates and re-injury of the anterior cruciate ligament (ACL) in patients submitted to single-bundle (SB) compared to double-bundle (DB) technique reconstruction. Methods: Athletes operated by SB or DB ACL reconstruction, with at least five years of follow-up at a single center, were included. The following data were collected: demographic data; competitive sports practice before the injury; previous surgery; injury/surgery to the contralateral knee; return to sports and level of the return; re-injury (time of the re-injury after the first surgery; mechanism of trauma for the re-injury; necessity of operative treatment); signs and complaints related to the knee the last clinical consultation. Results: Seventy-six athletes (27 SB and 49 DB) were included. The return to sport rate (98%) was the same for both groups, and the return to the previous level rate showed an improvement in the DB group but without statistical significance (63% vs. 79%; P = 0.173). However, other outcomes showed higher results for the DB group: lower re-injury rate throughout the follow-up period (41% vs. 18%; P = 0.034) and during the first year of follow-up (22% vs. 4%; P = 0.021), and less stiffness (0% vs. 22%, P = 0.001). While in primary reconstruction cases, there was not a higher re-injury rate using SB (P = 0.744), in the revision cases, SB was correlated with more re-injuries than DB (P = 0.002). Conclusion: The overall re-injury in the medium- and long-term and the return to practice sports at the same level as before surgery in athletes submitted to DB reconstruction were slightly better than those submitted to SB reconstruction, especially in the cases that were asecond time lesion ( revisioned knees).

Unravelling the surface structure of ß-Ga2O3 (100).

The present work is on a comprehensive surface atomic structure investigation of ß-Ga2O3 (100). The ß-Ga2O3 single crystal was studied by a structural model system in the simulations and in situ characterization via X-ray photoelectron spectroscopy (XPS), low-energy electron diffraction (LEED) and X-ray photoelectron diffraction (XPD) allowed for probing the outermost layers' properties. In situ XPD characterization allows for the collection of valuable element-specific short-range information from the ß-Ga2O3 surface, and the results were compared to a systematic and precise multiple scattering simulation approach. The experiments, characterizations, and simulations indicated strong evidence of considerable structural variations in the interatomic layer's distances. Such atomic displacement could clarify the electronic phenomena observed in theoretical studies. The comparison between experimental and theoretical XPD results involving multiple scattering calculations indicated that the ß-Ga2O3 surface has two possible terminations. The best fits to the photoelectron diffraction curves are used to calculate the interplanar relaxation in the first five atomic layers. The results show good agreement with previous density functional theory calculations, establishing XPD as a useful tool for probing the atomic structure of oxide surfaces.

X-ray photoelectron diffraction study of the approximant Al5Co2(001) quasicrystal.

The intermetallic Al5Co2 is defined as a structurally complex material and is considered a low-order quasicrystalline approximant. A single crystal of Al5Co2(001) was obtained by the Czochralski method. The sample was characterized by X-ray photoelectron spectroscopy (XPS), low-energy electron diffraction (LEED), and X-ray photoelectron diffraction (PED). The surface composition was also analyzed by XPS, indicating only Al and Co compounds. In the current research, the crystal structure was qualitatively analyzed using the LEED patterns for different incident beam energies indicating a (1 × 1) termination, also in accordance with some literature works. The structure study was performed by applying the standard software MSCD and showed a (1 × 1) pattern. In addition, four different termination models for this termination were tested. The reliability factor indicated that the best termination belongs to the Al-rich surface layer.

Nanohydroxyapatite/Titanate Nanotube Composites for Bone Tissue Regeneration.

Strategies for the production of new nanocomposites that promote bone tissue regeneration are important, particularly those that enhance the osteoinduction of hydroxyapatite in situ. Here, we studied and report the synthesis of nanohydroxyapatite and titanate nanotube (nHAp/TiNT) composites formulated at different concentrations (1, 2, 3, and 10 wt % TiNT) by means of a wet aqueous chemical reaction. The addition of TiNT affects the morphology of the nanocomposites, decreasing the average crystallite size from 54 nm (nHAp) to 34 nm (nHAp/TiNT10%), while confirming its interaction with the nanocomposite. The crystallinity index (CI) calculated by Raman spectroscopy and XRD showed that the values decreased according to the increase in TiNT concentration, which confirmed their addition to the structure of the nanocomposite. SEM images showed the presence of TiNTs in the nanocomposite. We further verified the potential cytotoxicity of murine fibroblast cell line L929, revealing that there was no remarkable cell death at any of the concentrations tested. In vivo regenerative activity was performed using oophorectomized animal (rat) models organized into seven groups containing five animals each over two experimental periods (15 and 30 days), with bone regeneration occurring in all groups tested within 30 days; however, the nHAp/TiNT10% group showed statistically greater tissue repair, compared to the untreated control group. Thus, the results of this study demonstrate that the presently formulated nHAp/TiNT nanocomposites are promising for numerous improved bone tissue regeneration applications.

Return to Sport and Re-Injury Rate after Double-Bundle Anterior Cruciate Ligament Reconstruction with at least Five Years of Follow-Up.

BACKGROUND: This study retrospectively evaluated the medium- and long-term results of patients submitted to double-bundle (DB) anterior cruciate ligament (ACL) reconstruction. METHODS: A retrospective study of case series at a single center. Cases submitted to isolated ACL reconstruction with at least five years of follow-up were included. The following data were collected: demographic data; practice of competitive sport before the injury; previous surgery; injury/surgery in the contralateral knee; return to the practices of sports and level; re-injury (postoperative time; mechanism; need for surgery); and symptoms at the last clinical follow-up visit. Descriptive and sub-group analyses were performed. RESULTS: Sixty-nine patients were included; 52 men (75%), 49 athletes (71%), 47 (68%) with primary injury, mean age of 30 years (SD 10). The patients were followed up for an average of 8.7 years (minimum 5, maximum 11.8) after surgery. After the reconstruction, 67 (97%) returned to the sport; 75% at the same level as before the injury. Ten patients (14%) suffered re-injury after an average of 32 months (between 9 and 50 months). Regarding the outcome of re-injury, no statistically significant differences were found between subgroups of athletes vs non-athletes or primary injury vs revision surgery, despite a significant tendency towards increased re-injury levels in athletes. However, this tendency was not statistically significant. CONCLUSION: In our series of patients operated on with the double-bundle technique and with a long follow-up time, 14% presented re-injury, with no differences between primary and revision cases, and with a trend towards higher re-injury levels among the athletes in relation to the non-athletes. The rate of return to sport was satisfactory, with 97%, of which 75% were playing at the same level as before the injury.

Ultrasound-guided foam sclerotherapy for chronic venous disease with ulcer. A prospective multiple outcome cohort study.

BACKGROUND: Chronic Venous Disease (CVD) is the main cause of chronic leg ulcers. Varicose veins are the most frequent cause of venous leg ulcers (VLU). 50.9% of Brazilian women have varicose veins and ulcer prevalence is as high as 4%. Ultrasound-guided foam sclerotherapy (UGFS) is a low-cost treatment option for varicose veins. OBJECTIVES: To analyze UGFS outcomes in patients with VLU. METHODS: Prospective consecutive single center cohort study. Patients with great saphenous vein (GSV) reflux and VLU were treated and followed-up for 180 days. The following were studied: quality of life (QoL), disease severity, healing, and elimination of GSV reflux. The Aberdeen questionnaire, a venous clinical severity score, and Duplex scanning (DS) results were analyzed. RESULTS: 22 patients aged 35 to 70 years were treated. There was improvement in quality of life, disease severity reduced, and ulcer diameter reduced (p < 0.001; ANOVA). 77.27% of VLU healed completely (95%CI: 59.76-94.78%). The dimensions of 20/22 VLU reduced (90.91%; 95%CI: 78.9-100%). GSV reflux was eliminated in 63.64% (95%CI: 43.54-83.74%). Men had greater QoL benefit and women had more complications. There were no severe complications. The VLU that had healed completely at the end of the study were smaller at baseline than those that did not completely heal. The GSV that were completely occluded at the end of the study were smaller at baseline than those that were not completely occluded (p < 0.05; Mann-Whitney). CONCLUSION: The results suggest that most patients benefited from UGFS.

CONTEXTO: A doença venosa crônica (DVC) é a principal causa de úlceras crônicas em membros inferiores. As varizes dos membros inferiores são a causa mais frequente de úlcera venosa (UV). No Brasil, 50,9% das mulheres têm varizes e a prevalência da úlcera chega a 4%. A escleroterapia ecoguiada com espuma (EEE) é uma alternativa de baixo custo para tratamento de varizes de membros inferiores. OBJETIVOS: Analisar evolução de portadores de UV tratados com EEE. MÉTODOS: Coorte prospectiva e consecutiva em um único serviço. Portadores de UV com veia safena magna (VSM) insuficiente foram acompanhados por 180 dias após EEE. Foram estudadas: qualidade de vida, gravidade da doença, cicatrização e eliminação do refluxo. Foram utilizados questionário Aberdeen, escore clínico venoso e ultrassom Doppler. RESULTADOS: Foram tratados 22 pacientes com idade entre 35 a 70 anos. Houve melhora na qualidade de vida, redução da gravidade da doença, e redução dos diâmetros das úlceras (p < 0.001; ANOVA). Houve redução das dimensões em 90,91% das úlceras [intervalo de confiança de 95% (IC95%) 78,9-100%], e cicatrização completa em 77,27% (IC95% 59,76-94,78%). O refluxo foi eliminado em 63,64% (IC95% 43,54-83,74%) das VSM. Homens tiveram maior benefício em qualidade de vida, e mulheres apresentaram mais complicações. Não houve complicações graves. As UV completamente cicatrizadas e as VSM que apresentaram oclusão completa apresentavam dimensões inicialmente menores quando comparadas às das UV não completamente cicatrizadas e das VSM não completamente ocluídas (p < 0,05; Mann-Whitney). CONCLUSÕES: Os resultados sugerem que EEE foi benéfica para a maioria dos pacientes.

Excision of a Posterior Cruciate Ligament Cyst Using an Arthroscopic Trans-septal Approach.

Posterior cruciate ligament (PCL) cysts are rare. Although they are usually asymptomatic and benign, in a few cases they may cause knee discomfort and restricted movements. Nonsurgical treatment is the initial approach, with medication and corticosteroid injections. However, there may be treatment failures, with some cysts needing to be excised surgically. Arthroscopic excision of PCL cysts located in the posterior compartment of the knee can be technically challenging. We describe the arthroscopic excision of a PCL cyst using a trans-septal portal, which is an easy and safe method for accessing and completely removing the lesion under direct vision.

Ultrasound-guided foam sclerotherapy for chronic venous disease with ulcer. A prospective multiple outcome cohort study / Escleroterapia ecoguiada com espuma para doença venosa crônica com úlcera: coorte prospectiva de múltiplos desfechos

Abstract Background Chronic Venous Disease (CVD) is the main cause of chronic leg ulcers. Varicose veins are the most frequent cause of venous leg ulcers (VLU). 50.9% of Brazilian women have varicose veins and ulcer prevalence is as high as 4%. Ultrasound-guided foam sclerotherapy (UGFS) is a low-cost treatment option for varicose veins. Objectives To analyze UGFS outcomes in patients with VLU. Methods Prospective consecutive single center cohort study. Patients with great saphenous vein (GSV) reflux and VLU were treated and followed-up for 180 days. The following were studied: quality of life (QoL), disease severity, healing, and elimination of GSV reflux. The Aberdeen questionnaire, a venous clinical severity score, and Duplex scanning (DS) results were analyzed. Results 22 patients aged 35 to 70 years were treated. There was improvement in quality of life, disease severity reduced, and ulcer diameter reduced (p < 0.001; ANOVA). 77.27% of VLU healed completely (95%CI: 59.76-94.78%). The dimensions of 20/22 VLU reduced (90.91%; 95%CI: 78.9-100%). GSV reflux was eliminated in 63.64% (95%CI: 43.54-83.74%). Men had greater QoL benefit and women had more complications. There were no severe complications. The VLU that had healed completely at the end of the study were smaller at baseline than those that did not completely heal. The GSV that were completely occluded at the end of the study were smaller at baseline than those that were not completely occluded (p < 0.05; Mann-Whitney). Conclusion The results suggest that most patients benefited from UGFS.

Resumo Contexto A doença venosa crônica (DVC) é a principal causa de úlceras crônicas em membros inferiores. As varizes dos membros inferiores são a causa mais frequente de úlcera venosa (UV). No Brasil, 50,9% das mulheres têm varizes e a prevalência da úlcera chega a 4%. A escleroterapia ecoguiada com espuma (EEE) é uma alternativa de baixo custo para tratamento de varizes de membros inferiores. Objetivos Analisar evolução de portadores de UV tratados com EEE. Métodos Coorte prospectiva e consecutiva em um único serviço. Portadores de UV com veia safena magna (VSM) insuficiente foram acompanhados por 180 dias após EEE. Foram estudadas: qualidade de vida, gravidade da doença, cicatrização e eliminação do refluxo. Foram utilizados questionário Aberdeen, escore clínico venoso e ultrassom Doppler. Resultados Foram tratados 22 pacientes com idade entre 35 a 70 anos. Houve melhora na qualidade de vida, redução da gravidade da doença, e redução dos diâmetros das úlceras (p < 0.001; ANOVA). Houve redução das dimensões em 90,91% das úlceras [intervalo de confiança de 95% (IC95%) 78,9-100%], e cicatrização completa em 77,27% (IC95% 59,76-94,78%). O refluxo foi eliminado em 63,64% (IC95% 43,54-83,74%) das VSM. Homens tiveram maior benefício em qualidade de vida, e mulheres apresentaram mais complicações. Não houve complicações graves. As UV completamente cicatrizadas e as VSM que apresentaram oclusão completa apresentavam dimensões inicialmente menores quando comparadas às das UV não completamente cicatrizadas e das VSM não completamente ocluídas (p < 0,05; Mann-Whitney). Conclusões Os resultados sugerem que EEE foi benéfica para a maioria dos pacientes.

Professional Athletes Are at Higher Risk of Septic Arthritis After Anterior Cruciate Ligament Reconstruction: An Analysis of 4421 Consecutive Patients Including 265 Elite Athletes From the SANTI Study Group.

BACKGROUND: Professional athletes are reported to be at greater risk of septic arthritis (SA) after anterior cruciate ligament reconstruction (ACLR) than the nonprofessional population. However, this finding has been controversial, and confusion has arisen in the literature owing to the underpowering of previous studies. PURPOSE/HYPOTHESIS: The purpose was to report the differences in the rate of SA after ACLR in a large series of patients and to perform pooled data analysis including previously published studies. The hypothesis was that professional athletes have a significantly higher risk of SA than nonprofessional athletes. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A retrospective analysis of prospectively collected data was performed. Patients who underwent ACLR between January 2009 and July 2017 (with a minimum follow-up of 12 months) were considered for study eligibility. The rate of SA was determined, and multivariate analysis was used to evaluate potentially important risk factors, including participation in professional sport. Furthermore, a literature search was performed, and data were extracted from all identified relevant studies. A pooled data analysis was performed to determine differences in the risk of SA between professional and nonprofessional populations. RESULTS: The current series comprised 4421 anterior cruciate ligament surgical procedures with 265 professional athletes. There were 15 cases of SA diagnosed over the study period (0.34%; 95% CI, 0.19%-0.56%). Ten cases occurred in professional athletes (3.8%; 95% CI, 1.82%-6.83%). The percentage of SA was 0.12% (95% CI, 0.04%-0.28%) in the nonprofessional population. Being a professional athlete was associated with a significantly increased risk of SA after ACLR (odds ratio, 21.038; 95% CI, 6.585-75.789; P < .0001). This finding was confirmed in the pooled data analysis comprising 11,416 patients including 1118 professional athletes (odds ratio, 5.03; 95% CI, 1.17-21.61). CONCLUSION: Professional athletes are at greater risk of SA after ACLR than nonprofessional athletes. The results of previous studies may have been conflicting owing to underpowering. The current study confirms the elevated risk by using a large clinical series and pooled data analysis to avoid the limitations of previous studies.

Anterior Closing-Wedge Osteotomy for Posterior Slope Correction With Tibial Tubercle Preservation.

An excessive posterior tibial slope has been identified as a potential risk factor for anterior cruciate ligament tears. Anterior closing-wedge osteotomy decreases the posterior slope and can eliminate this risk factor in patients with recurrent instability and greater than 12° posterior slope. We will describe an anterior closing-wedge osteotomy technique performed at the tibial tubercle (TT), in which the TT is not detached to preserve the extensor mechanism attachment. A vertical cut is performed in the sagittal plane just posterior to the TT, leaving a distal cortical hinge. Two proximal parallel K-wires and 2 distal parallel K-wires convergent to the proximal ones are inserted from the anterior cortex on both sides of the tubercle toward the tibial posterior cortex at the posterior cruciate ligament's tibial insertion. Proximal and distal cuts are performed to remove the bone wedge. Reduction is achieved by gentle knee extension. Fixation is completed with 2 staples placed medially and laterally to the TT.

Ultrasound-guided foam sclerotherapy for severe chronic venous insufficiency.

Chronic venous insufficiency is characterized by cutaneous alterations caused by venous hypertension; in severe forms, it progresses to lower limb ulcers. Lower limb varicose veins are the main cause of chronic venous insufficiency, and the classic treatment includes surgery and compressive therapy. Minimally invasive alternative treatments for varicose veins include new techniques such as venous thermal ablation using laser or radiofrequency. The use of different methods depends on clinical and anatomical factors. Ultrasound-guided foam sclerotherapy is the venous injection of sclerosing foam controlled by Doppler ultrasound. Sclerotherapy is very useful to treat varicose veins, and probably, is cheaper than other methods. However, until the present, it is the less studied method.

Ultrasound-guided foam sclerotherapy for severe chronic venous insufficiency / Escleroterapia ecoguiada com espuma para tratamento da insuficiência venosa crônica grave

ABSTRACT Chronic venous insufficiency is characterized by cutaneous alterations caused by venous hypertension; in severe forms, it progresses to lower limb ulcers. Lower limb varicose veins are the main cause of chronic venous insufficiency, and the classic treatment includes surgery and compressive therapy. Minimally invasive alternative treatments for varicose veins include new techniques such as venous thermal ablation using laser or radiofrequency. The use of different methods depends on clinical and anatomical factors. Ultrasound-guided foam sclerotherapy is the venous injection of sclerosing foam controlled by Doppler ultrasound. Sclerotherapy is very useful to treat varicose veins, and probably, is cheaper than other methods. However, until the present, it is the less studied method.

RESUMO A insuficiência venosa crônica é caracterizada por alterações cutâneas decorrentes da hipertensão venosa que, nas formas graves, evoluem com úlceras nos membros inferiores. As varizes dos membros inferiores são a causa mais frequente de insuficiência venosa crônica, que tem como tratamentos clássicos a cirurgia de varizes e a terapia compressiva. Novas técnicas de termo-ablação venosa por laser e radiofrequência são alternativas minimamente invasivas para o tratamento de varizes. A aplicabilidade dos diferentes métodos é limitada por requisitos anatômicos e clínicos. A escleroterapia ecoguiada com espuma consiste na injeção endovenosa da espuma esclerosante monitorada pelo Ultrassom Doppler. A escleroterapia tem grande aplicabilidade para tratamento das varizes e, provavelmente, é mais barato que outros métodos. Entretanto é, até o momento, o método menos estudado.

Estimates for genetic variance components in reciprocal recurrent selection in populations derived from maize single-cross hybrids.

This study was carried out to obtain the estimates of genetic variance and covariance components related to intra- and interpopulation in the original populations (C0) and in the third cycle (C3) of reciprocal recurrent selection (RRS) which allows breeders to define the best breeding strategy. For that purpose, the half-sib progenies of intrapopulation (P11 and P22) and interpopulation (P12 and P21) from populations 1 and 2 derived from single-cross hybrids in the 0 and 3 cycles of the reciprocal recurrent selection program were used. The intra- and interpopulation progenies were evaluated in a 10 × 10 triple lattice design in two separate locations. The data for unhusked ear weight (ear weight without husk) and plant height were collected. All genetic variance and covariance components were estimated from the expected mean squares. The breakdown of additive variance into intrapopulation and interpopulation additive deviations (σ τ (2)) and the covariance between these and their intrapopulation additive effects (Cov Aτ) found predominance of the dominance effect for unhusked ear weight. Plant height for these components shows that the intrapopulation additive effect explains most of the variation. Estimates for intrapopulation and interpopulation additive genetic variances confirm that populations derived from single-cross hybrids have potential for recurrent selection programs.

Traumatic arteriovenous fistula of the superficial temporal artery / Fístula arteriovenosa traumática de artéria temporal superficial

Arteriovenous fistulae of the superficial temporal artery are rare, and their principal cause is traumas. Complications include pulsatile mass, headache, hemorrhage and deformities that compromise esthetics. Treatment can be performed using conventional surgery or endovascular methods. The authors describe a case of a 44-year-old male patient who developed a large pulsating mass, extending from the preauricular region to the right parietotemporal and frontal regions after a motorcycle accident. The treatment chosen was complete surgical removal of the pulsatile mass and ligature of the vessels feeding the fistula.

As fístulas arteriovenosas de artéria temporal superficial são raras, sendo o trauma sua etiologia principal. Suas complicações incluem massa pulsátil, cefaleia, hemorragia e deformidade estética. O tratamento pode ser realizado por cirurgia convencional ou endovascular. Os autores relatam o caso de um paciente de 44 anos que evoluiu com massa pulsátil extensa desde região pré-auricular até região parietotemporal e frontal direita após acidente motociclístico. Optou-se por remoção cirúrgica completa da massa pulsátil e ligadura dos vasos nutridores da fístula.

True posttraumatic radial artery aneurysm / Aneurisma verdadeiro de arteria radial pos-traumatico

Radial artery aneurysms are rare and mostly secondary to traumatic events (posttraumatic pseudoaneurysms). Radial artery aneurysms should be treated due to the high risk of embolization, thrombosis, and compression of adjacent nerves. The authors describe a case of a 49-year-old patient complaining of a progressively growing tumor in the left wrist after a dog bite. The tumor proved to be a true posttraumatic aneurysm. Treatment consisted of removal of the aneurysm sac and ligation of the radial artery.

Os aneurismas de artéria radial são raros, sendo, na maioria das vezes, pseudoaneurismas pós-traumáticos. Os aneurismas de artéria radial devem ser tratados devido ao risco de embolização, trombose e compressão de estruturas nervosas adjacentes. Os autores relatam o caso de um paciente de 49 anos referindo tumoração de crescimento progressivo em punho esquerdo após mordedura canina, sendo diagnosticado aneurisma verdadeiro de artéria radial pós-traumático. Optou-se pela ressecção do saco aneurismático e ligadura da artéria radial.

Dissecção espontânea da aorta abdominal infrarrenal / Spontaneous dissection of the infrarenal aorta

A rotura da camada íntima que marca o início da dissecção aórtica se origina na maioria dos casos na aorta torácica, sendo rara a dissecção espontânea da aorta abdominal infra-renal. As três principais causas são: iatrogênica, traumática ou espontânea. A dor abdominal e a isquemia de membros são os sintomas mais comuns e um número significativo de pacientes e´ assintomatico. O diagnóstico tem sido feito através de métodos de imagem como ultrassonografia, tomografia computadorizada, ressonância nuclear magnética e angiografia aliados ao alto índice de suspeição. Relatamos os casos de duas pacientes que apresentaram dissecção de aorta abdominal infrarrenal com quadro de dor abdominal súbita, sem sinais de irritação peritoneal com pulsos presentes e simétricos ao exame físico que deram entrada no pronto socorro do Hospital e Maternidade Celso Pierro da PUC Campinas e que foram tratadas pela equipe de Cirurgia Vascular. As duas pacientes no momento do exame apresentavam-se hipertensas e ao ultrassom apresentavam alteração da conformidade da aorta abdominal que foram tratada s cirurgicamente. Uma paciente foi tratada cirurgicamente submetida a endarterectomia da placa dissecada da aorta abdominal infrarrenal de 2,2 cm de diâmetro e 2,0 cm de extensão. A outra paciente foi submetida a revascularização da aorta abdominal bi-iliaca com prótese de Dacron 16 × 8 mm por apresentar disseccao da aorta abdominal distal. As duas pacientes apresentaram boa evolução pos-operatoria tendo alta hospitalar em bom estado geral.

The rupture of the intimal layer marks the beginning of the aortic dissection, which usually happens in the thoracic aorta. The spontaneous dissection of the infrarenal aorta is rare. The main causes are: iatrogenic, traumatic and spontaneous. Abdominal pain and limb ischemia are the commonest symptoms, and some patients are asymptomatics. The diagnosis is made by ultrasound, computed tomography, nuclear magnetic resonance and angiography, with a high suspicious index. We describe two cases of spontaneous rupture of the infrarenal aorta that were treated surgically. We report two cases of patients who were admitted to the emergency room of Celso Pierro Hospital with infrarenal abdominal aortic dissection and were treated by the vascular surgery group. They have presented sudden abdominal pain, no signs of peritoneal irritation and pulses were presents and simmetrics in physical examination The two patients during the examination were hypertensive and the ultrasound showed abnormal compliance of the abdominal aorta who were treated surgically. One patient was treated surgically with dissected plaque endarterectomy of infrarenal abdominal aorta of 2.2 cm in diameter and 2.0 cm in length. The other patient underwent revascularization of the abdominal aorta with bi-iliac Dacron graft 16 × 8 mm due to distal abdominal aortic dissection. Both patients had good postoperative evolution and they were discharged in good general condition.

Germination ecophysiology of Annona crassiflora seeds.

BACKGROUND AND AIMS: Little is known about environmental factors that break morphophysiological dormancy in seeds of the Annonaceae and the mechanisms involved. The aim of this study was to characterize the morphological and physiological components of dormancy of Annona crassiflora, a tree species native to the Cerrado of Brazil, in an ecophysiological context. METHODS: Morphological and biochemical characteristics of both embryo and endosperm were monitored during dormancy break and germination at field conditions. Seeds were buried in the field and exhumed monthly for 2 years. Germination, embryo length and endosperm digestion, with endo-beta-mannanase activity as a marker, were measured in exhumed seeds, and scanning electron microscopy was used to detect cell division. The effect of constant low and high temperatures and exogenous gibberellins on dormancy break and germination was also tested under laboratory conditions. KEY RESULTS: After burial in April, A. crassiflora seeds lost their physiological dormancy in the winter months with lowest monthly average minimum temperatures (May-August) prior to the first rainfall of the wet season. The loss of physiological dormancy enabled initiation of embryo growth within the seed during the first 2 months of the rainy season (September-October), resulting in a germination peak in November. Embryo growth occurred mainly through cell expansion but some dividing cells were also observed. Endosperm digestion started at the micropylar side around the embryo and diffused to the rest of the endosperm. Exogenous gibberellins induced both embryo growth and endo-beta-mannanase activity in dormant seeds. CONCLUSIONS: The physiological dormancy component is broken by low temperature and/or temperature fluctuations preceding the rainy season. Subsequent embryo growth and digestion of the endosperm are both likely to be controlled by gibberellins synthesized during the breaking of physiological dormancy. Radicle protrusion thus occurred at the beginning of the rainy season, thereby maximizing the opportunity for seedlings to emerge and establish.