Cortical stimulation leads to shortened myelin sheaths and increased axonal branching in spared axons after cervical spinal cord injury.

Neural activity and learning lead to myelin sheath plasticity in the intact central nervous system (CNS), but this plasticity has not been well-studied after CNS injury. In the context of spinal cord injury (SCI), demyelination occurs at the lesion site and natural remyelination of surviving axons can take months. To determine if neural activity modulates myelin and axon plasticity in the injured, adult CNS, we electrically stimulated the contralesional motor cortex at 10 Hz to drive neural activity in the corticospinal tract of rats with sub-chronic spinal contusion injuries. We quantified myelin and axonal characteristics by tracing corticospinal axons rostral to and at the lesion epicenter and identifying nodes of Ranvier by immunohistochemistry. Three weeks of daily stimulation induced very short myelin sheaths, axon branching, and thinner axons outside of the lesion zone, where remodeling has not previously been reported. Surprisingly, remodeling was particularly robust rostral to the injury which suggests that electrical stimulation can promote white matter plasticity even in areas not directly demyelinated by the contusion. Stimulation did not alter myelin or axons at the lesion site, which suggests that neuronal activity does not contribute to myelin remodeling near the injury in the sub-chronic period. These data are the first to demonstrate wide-scale remodeling of nodal and myelin structures of a mature, long-tract motor pathway in response to electrical stimulation. This finding suggests that neuromodulation promotes white matter plasticity in intact regions of pathways after injury and raises intriguing questions regarding the interplay between axonal and myelin plasticity.

[Hepatosplenic schistosomiasis portal hypertension: effect of esophagogastric devascularization with splenectomy on the diameter and mean flow velocity in the portal system (ultra-sonographic Doppler]. / Hipertensão portal por esquistossomose mansônica hepatoesplênica: efeito da desconexão ázigo-portal com esplenectomia no diâmetro e na velocidade média de fluxo do sistema portal (estudo ultra-sonográfico com Doppler).

BACKGROUND: Esophagogastric devascularization with splenectomy has been used for the treatment of upper digestive bleeding due to esophagic varices in hepatoportal mansoni's schistosomic portal hypertension. Nevertheless, early portal thrombosis has hampered this surgical technique (13.3% and 53.2%), compromising the good results on the hemorrhagic side. Supposing that portal circulatory changes, due to the surgical treatment, may play an important role in this kind of complication, our objective was to identify the hemodynamic facilitating factors. Portal hemodynamic aspects, identified by ultra-sonographic Doppler study, from two groups of patients: non-operated upon and splenectomized with esophagogastric devascularization in late post-operatory phase (in excess of 6 moths), with portal hypertension due to mansoni hepatoesplenic portal hypertension and in similar clinical conditions, were compared. METHOD: Fifty eight ambulatorial patients were studied, all had portal hypertension caused by mansoni's hepatosplenic schistosomiasis and previous bouts of digestive bleeding. They were divided in two groups: A--29 followed clinically/endoscopically, and group B--29 previously submitted to esophagogastric devascularization with splenectomy. In all was measured the diameter and mean flow velocity in the portal vein and its right and left branches by ultra-sonographic Doppler study. The results were submitted to statistical analysis for inter- and intra-group comparison. RESULTS: Group A (non-operated): the portal vein diameter was greater than the right and left branches (10.6 +/- 2.9, 8.0 +/- 1.8, 9.1 +/- 2.6 cm), the mean flow velocities in the portal vein and its branches were similar (15.62 +/- 6.17, 14.92 +/- 5.33, 16.12 +/- 4.18 cm/seg). Group B (operated): the diameter and mean flow velocity in all vessels were reduced (8.8 +/- 1.7, 5.2 +/- 1.2, 7.5 +/- 2.2 cm/12.53 +/- 2.60, 8.86 +/- 1.75, 9.69 +/- 3.75 cm/seg). CONCLUSIONS: After esophagogastric devascularization with splenectomy, there was a reduction of the diameter and mean flow velocity in the portal vein, its right and left branches.

[Doppler ultrasonography evaluation of paraumbilical vein and portal hypertension]. / Evaluation par échographie-Doppler de la veine para-ombilicale dans l'hypertension portale.

UNLABELLED: Portal hypertension is associated to the development of portosystemic collateral veins, particularly the paraumbilical vein. PURPOSE: To evaluate the biometric and hemodynamic characteristics of the portal vessels related to the presence of a patent paraumbilical vein, in the setting of portal hypertension secondary to hepatosplenic schistosomiasis. METHODS: 75 patients with portal hypertension secondary to hepatosplenic schistosomiasis were evaluated by Doppler US. The patients were studied based on the presence (group B) or not (Group A) of a patent paraumbilical vein. The diameter and blood flow velocity of the portal vessels and of the paraumbilical vein were recorded. RESULTS: The paraumbilical vein was detected in 17.33% of patients. The results showed an increase of the diameter of the main and left portal vessels whenever a patent paraumbilical vein was present (portal vein: A = 1.14 +/- 0.29 cm/B = 1.33 +/- 0.16 cm; left branch: A = 0.95 +/- 0.25 cm/B = 1.30 +/- 0.24 cm). The mean blood flow velocity was also increased in the portal trunk (A = 15.96 +/- 6.17 cm/sec/B = 19.82 +/- 6.26 cm/sec) and in the left portal branch (A = 14.77 +/- 4.29 cm/sec/B = 19.92 +/- 6.88 cm/sec). CONCLUSION: The presence of a patent paraumbilical vein is related to significant biometric and hemodynamic variations in the portal venous system, in the setting of portal hypertension secondary to hepatosplenic schistosomiasis.

[Patent paraumbilical vein: hemodynamic importance in Mansoni's hepatosplenic portal hypertension (Study with ultrasonography Doppler]. / Veia paraumbilical pérvia: importância hemodinâmica na hipertensão portal por esquistossomose mansônica hepatoesplênica. (Estudo com ultra-sonografia Doppler).

BACKGROUND: The hemodynamical effect of the collateral portosystemic circulation upon the portal system has not yet been fully understood. The US-Doppler made possible the non-invasive study of the portal system by evaluating the parameters: flow direction, diameter and flow velocity in it's vessels. AIMS: To study the paraumbilical vein as a collateral portosystemic pathway and identify patterns for appraising its hemodynamic importance to the portal system. METHOD: US-Doppler study of the portal system of 24 patients with Mansoni's hepatosplenic schistosomic portal hypertension, previous esophagic variceal bleeding and patent paraumbilical vein with hepatofugal flow. The diameter and the mean flow velocity were measured in the paraumbilical vein and so were the mean flow velocity in the portal vein, right and left portal branches. The Pearson test (linear correlation) was applied to the portal vein's mean flow velocity and the paraumbilical vein's diameter and mean flow velocity. The patients were divided in four groups: D1-paraumbilical vein with diameter < 0.68 cm (n = 14), D2-paraumbilical vein with diameter > or = 0.68 cm (n = 10), V1-paraumbilical vein with mean flow velocity < 18.41 cm/seg (n = 13) and V2-paraumbilical vein with mean flow velocity > or = 18.41 cm/seg (n = 11). The mean flow velocity in the portal vein, right and left portal branches of the four groups were compared. RESULTS: The paraumbilical vein diameter was 0.68 +/- 0.33 cm (range: 0.15-1.30 cm) and the mean flow velocity was 18.41 +/- 11.51 cm/seg (range: 5.73-38.20 cm/seg). The linear correlation between the portal vein's mean flow velocity/paraumbilical vein diameter and the paraumbilical vein's mean flow velocity showed r = 0.504 and r = 0.735, respectively. In the group D2 there was an increase in the mean flow velocity in the portal vein (17.80 +/- 3.42/22.30 +/- 7.67 cm/seg) and in the left portal branch (16.00 +/- 4.73/22.40 +/- 7.90 cm/seg). In the group V2 there was an increase in the mean flow velocity in the portal vein (16.31 +/- 3.49/21.96 +/- 5.89 cm/seg) and in the left portal branch (14.22 +/- 4.41/21.94 +/- 7.20 cm/seg). There was no change in the right portal branch (13.67 +/- 5.74/15.43 +/- 3.43 cm/seg). CONCLUSIONS: In portal hypertension due to hepatosplenic schistosomiasis, the patent paraumbilical vein, with hepatofugal flow, diameter > or = 0.68 cm and mean flow velocity > or = 18.41 cm/seg causes an increase of the mean flow velocity in the portal vein and left portal branch. The best US-Doppler parameter to appraise the paraumbilical vein influence upon the portal system is the mean flow velocity. The correlation between the increase in portal vein's mean flow velocity is stronger with the paraumbilical vein's mean flow velocity than with its diameter. The increase in the portal vein's and left portal branch's mean flow velocity may be understood as the paraumbilical vein's hemodynamic influence upon the portal system. An active portosystemic collateral pathway increases the mean flow velocity in the vein's segment proximal to its point of origin.

[Intrahepatic transtumoral arteriovenous fistulae (diagnosis, importance, therapeutic proposals)]. / Fístulas arteriovenosas intra-hepáticas transtumorais (diagnóstico, importância e propostas de tratamento).

The authors present the angiographic aspects of four patients having an arteriovenous transhepatic transtumoral fistula (two arterioportal and two arteriovenous). The angiographic results of the occlusion with cyanoacrylate (Hystoacryl) of the right hepatic artery in one and by the infusion of Lipiodol in two are also shown. The physiopathological characteristics of each kind of fistula are discussed and the consequences of the passage of the quimioembolizing mixture through the tumor, regarding intrahepatic abscess formation, irregular clinical results and pulmonary complications are commented. These complications make the diagnosis of a transtumoral transhepatic arteriovenous fistula, previously to the chemoembolic treatment important, even though being frequently difficult, because of the reduced caliber of the feeding artery and eventual low transfistular bloodflow. The efficient occlusion of the arterioportal fistula with Histoacryl was favourably compared to the infusion of Lipiodol, which was unable to occlude the arteriovenous fistula. The contraindication to perform chemoembolic treatment of hepatic tumors, when an intrahepatic transtumoral arteriovenous fistula is present and the embolization of the fistular feeding artery is stressed. Ultrasonography using color Doppler and sono-enhancing contrast is appointed as the ideal non-invasive means of making the diagnosis of an hepatic transtumoral fistula and makes it eligible to be the first test in the algorithm for the appraisal of hepatic tumors.

Colour Doppler ultrasound: a new index improves the diagnosis of renal artery stenosis.

The description of a new index, the renal-segmental ratio (RSR), and the comparison of its performance with other conventional Doppler parameters for the detection of renal artery stenosis (RAS). A total of 96 renal units were studied with angiography and colour Doppler ultrasound (US) independently. The Doppler parameters applied were: 1. renal artery peak systolic velocity (RE-PSV), 2. renal-aortic ratio (RAR), 3. early systolic acceleration (ESA), and 4. renal-segmental ratio (RSR). The angiographic study was used as the "gold standard" for the identification of > or = 50% RAS. The results indicate that RSR (sensitivity: 93.33%, specificity: 89.47%) and RE-PSV (sensitivity: 83.33%, specificity: 89.47%) were the best criteria for RAS diagnosis (p values <0.05). The results show that colour Doppler US is a reliable diagnostic modality for RAS diagnosis. The new index (RSR) improves the effectiveness of the method.

[Atherosclerotic stenosis of the main branches of abdominal aorta. (Prevalence in patients with lower limb occlusive vascular disease)]. / Estenose aterosclerótica dos principais troncos arteriais da aorta abdominal. (Prevalência em pacientes com arteriopatia oclusiva dos membros inferiores).

The authors present the radiographical study of the aortographies of 100 consecutive patients with symptomatic atherosclerotic ischemia of the lower limbs in whom were appraised the stenosis of the celiac trunk, superior mesenteric artery, renal arteries and the presence of the inferior mesenteric artery. The parameters observed were: age, sex, solitary and concomitant stenosis. Seven patients were excluded: six because of arteritis and one because could not be analyzed. Sixty four (68.81%) of the remaining 93 patients had important stenosis (> 30%) of one or more branches of the abdominal aorta, which had a steep raise in number from the 60 decade on. There was no difference regarding to the sex of the patients. The more frequently found solitary stenosis was that of the celiac trunk (16-16.1%) followed by the renal (13-13.0%) and in the concomitant was that of the celiac trunk/renal artery (8-8.6%) and celiac trunk/superior mesenteric artery (5-5.3%). They conclude that in spite of the great number of stenosis of the branches of the abdominal aorta in this kind of patients, there was a low incidence of the concomitant stenosis of the celiac trank/superior mesenteric artery, being difficult to characterize radiologically the digestive ischemic syndrome. They point out that this highly selected group of patients, because of their basic disease, should be more extensively studied in order to identify the results of those vascular stenosis on their digestive tract and orient its eventual treatment.

[Angiographic aspects of the hepatic veins in portal hypertension in schistosomiasis. The importance in assessing the hepatic vein pressure]. / Aspectos angiográficos das veias hepáticas na hipertensão portal esquistosomótica. (Importância na medida da pressão venosa hepática).

The authors comment upon the importance of the hepatic wedged venous pressure for the appraisal of the circulatory conditions of the portal system, mainly in cirrhotic patients. Wondering about the irregular results obtained in the study of schistosomotic portal hypertensive patients by occlusive catheterization and with the use of an occlusive balloon catheter, noted the scarcity of angiographic studies on the subject in this pathology. Present the angiographic aspects that were obtained from patients with schistosomotic portal hypertension complicated by digestive bleeding, by means of injecting the contrast material into a hepatic vein of the right hepatic lobe via a loosely introduced catheter. Those radiological aspects were distributed in two categories: 1) type I-presenting variable sinusoidal filling. Presence of anastomotic intraparenquimatous communications with or without calibrous anastomotic veins between the hepatic veins, 2) type II-presenting no sinusoidal filling. Presence of multiple anastomotic communications of varied calibers between the hepatic veins. Commenting the difficulty of assessing the wedged pressure in patients with schistosomotic portal hypertension because of the easy communication between the hepatic veins, the authors point out that the measured pressure, in all the cases, will be that of the opposite hepatic vein. That pressure, in this pathology, might represent the sinusoidal resistance (when present) between hepatic veins, instead of relating to the portal vein. Suggestion is made that the measure of the wedged hepatic pressure, in patients with schistosomotic portal hypertension, be appraised considering the angiographic aspects of the hepatic veins.

[Splanchnic portal circulation (enhancement of radiologic image intensity and of visibility of collateral branches with prostaglandin E1)]. / Circulação portal esplâncnica. (Reforço da intensidade da imagem radiológica e aumento da visibilização de colaterais com emprego da prostaglandina E1).

The authors present the results of a comparative study of mesenterico-portographies with and without the use of Prostaglandin E1 (PGE1) injected intrarterially into the superior mesenteric artery as an adjunct to the radiographic procedure. Twenty eight patients, with varied hepatic and biliopancreatic ailments, referred to the Radiologic Department for angiographic appraisal of the splanchnic circulation were studied. Two series of radiographies were realized after catheterization of the superior mesenteric artery: a first after the injection of the contrast only and a second after the injection of 50 micrograms of PGE1 as a bolus prior the contrast means. The difference in opacification of the various segments of the portal system and the lapse of time necessary to attain the maximum radiographic density were appraised. They observed that, with the use of PGE1 was attained a regular, intense and swift opacification of the superior mesenteric vein, portal vein and intrahepatic branches in all patients that had those segments previous and/or hepatotropic circulation. There was a significative reduction in the lapse of time necessary to attain the maximum opacification. Also they observed, with the use of the PGE1, the opacification of collateral branches of the portal system in more patients and intensification in those that were previously opacified. Because of the good results attained with the use of the PGE1, its transitory pharmacologic action and absence of collateral reactions with the dose used, they recommend its regular use when this investigation is performed.

[Portal thrombosis: early complication of azygo-portal disconnection in the treatment of bleeding esophageal varices]. / Trombose portal: complicação precoce da desconexão ázigo-portal no tratamento das varizes esofagianas sangrantes.

The authors studied 30 patients with bleeding from esophageal varices due to portal hypertension. They underwent the disconnection of portal and azygos veins and splenectomy. The immediate postoperative complications were: portal thrombosis in four patients (13.3%); subphrenic abscess in two (6.6%); pulmonary embolism in one (3.3%) and esophageal perforation in one (3.3%). The manifestations of portal thrombosis were ascites, and fever (without leukocytosis). One patient with portal thrombosis who had intractable ascite was submitted to peritoneovenous shunting.

Occupied and unoccupied type II estrogen binding sites in human breast cancer.

Using a saturation analysis over a wide range of [3H]estradiol at two temperatures 4 and 22 degrees C we have determined unoccupied (4 degrees C) and total (22 degrees C) type II estrogen binding site (EBS) levels in individual cytosols of 100 patients with breast cancer (50 post and 50 premenopausal). Exchange was found to be complete after 18 h at 22 degrees C and receptor degradation was negligible during this treatment. Steroid specificity and affinity determined by Scatchard and Rosenthal plot analysis were not altered at 22 degrees C. Carcinomas presented a higher total type II REBS level as compared unfilled type II binding sites or the classical ER, independently of menopausal status, phase of the menstrual cycle or positivity of ER. On the other hand, unoccupied type II EBS level was strongly correlated to the concentration of type I ER, being higher on the post-menopausal group and older patients.

Steroid hormone receptors in male breast diseases.

Estrogen (ER), progesterone (PR), glucocorticoid (GR) and androgen (AR) receptors were assayed in tumor samples from 8 cases of male breast cancer (MBC) and 20 cases of male gynecomastia. Seven out of eight (87.5%) male tumor samples had positive ER assays with values ranging from 12 to 180 fmol/mg protein. Of the seven ER positive cases of MBC, six, had positive PR activity with high titers. Positive GR and AR values were also detected in 75% of MBC cases. Concentrations of all four receptors were significantly correlated with each other. With gynecomastic tissue, the proportion of receptor-positive patients was 20% ER, 20% PR, 20% AR, and 45% GR. Except for GR, steroid receptor values for MBC individuals were significantly higher than those of gynecomastia patients.

Afinidade da ligaçäo do deflazacort aos receptores de glicorticóide / Binding affinity of deflazacort to glucocorticoid receptors

O deflazacort (DF) é um glicocorticóide mais potente que prednisolona (P) como agente anti-inflamatório e timolítico. Utilizando como sonda radioativa (3H) dexametazona e concentraçöes crescentes de vários esteróides frios, determinamos a afinidade do DF e da P ao receptor de glicocorticóide presente em citosol de fígado, timo e hipófise de ratos adrenalectomizados. Verificamos que nos três tecidos examinados, há correlaçäo entre as afinidades determinadas e os efeitos timolítico e anti-inflamatório

[Estrogen and progesterone receptors in uterine cervix]. / Receptores de estrogeno e progesterona em cervix uterina.

PIP: This report describes the measurement of estrogen (ER) and progesterone receptors (PR) in cytosols of human exocervix and endometrium, using a charcoal dextran method. Endometrial tissues were obtained from patients undergoing hysterectomy. Curettage specimens of exocervix were obtained from healthy women throughout the menstrual cycle, from women taking combined oral contraceptives, and from postmenopausal women. The highest ER and PR concentrations and ER/PR ratio were detected in endometrium. Exocervix ER and PR levels were lower as compared to endometrium (14% and 3.6% respectively) and no cyclic variations were detectable. Specimens of exocervix from women taking oral contraceptives showed a significant PR decrease. In postmenopausal women, cervical ER and PR levels were significantly higher than in premenopausal women. No difference in binding specificity of estradiol and progesterone to their receptors could be found between endometrium and exocervix. The authors concluded that the effect of estrogen and progesterone on the cervix is limited by the low cytoplasmic receptor levels.^ieng

Percutaneous transluminal angioplasty of renal artery stenosis.

Percutaneous transluminal angioplasty was performed in 7 patients with hypertension and renal artery stenosis, caused by atherosclerosis in 3 patients and fibromuscular disease in 4. The balloon dilatation was successful in all patients. In 6 patients the blood pressure was normalized within 5 days after the procedure, and remained so in 5 on follow up 3 to 10 months later.