Myogenic Potential of Extracellular Matrix Derived from Decellularized Bovine Pericardium

Skeletal muscles represent 40% of body mass and its native regenerative capacity can be permanently lost after a traumatic injury, congenital diseases, or tumor ablation. The absence of physiological regeneration can hinder muscle repair preventing normal muscle tissue functions. To date, tissue engineering (TE) represents one promising option for treating muscle injuries and wasting. In particular, hydrogels derived from the decellularized extracellular matrix (dECM) are widely investigated in tissue engineering applications thanks to their essential role in guiding muscle regeneration. In this work, the myogenic potential of dECM substrate, obtained from decellularized bovine pericardium (Tissuegraft Srl), was evaluated in vitro using C2C12 murine muscle cells. To assess myotubes formation, the width, length, and fusion indexes were measured during the differentiation time course. Additionally, the ability of dECM to support myogenesis was assessed by measuring the expression of specific myogenic markers: α-smooth muscle actin (α-sma), myogenin, and myosin heavy chain (MHC). The results obtained suggest that the dECM niche was able to support and enhance the myogenic potential of C2C12 cells in comparison of those grown on a plastic standard surface. Thus, the use of extracellular matrix proteins, as biomaterial supports, could represent a promising therapeutic strategy for skeletal muscle tissue engineering.

Hypertensive Encephalopathy: Clinical and Neuroradiological Findings

Hypertensive encephalopathy is a syndrome consisting of headache, seizures, visual changes, and other neurologic disturbances in patients with elevated systemic blood pressure. The purpose of this study was to analyse the clinical and neuroradiological findings in nine patients with hypertensive encephalopathy, observed in five years.

CT (n = 13), and MR (n = 12), examinations performed in these patients before and after resolution of symptoms were reviewed. Six had the preeclampsia-eclampsia syndrome, and three had hypertensive encephalopathy due to other causes. CT and MR findings in all patients having these examinations were indicative of oedema in the cortex and subcortical white matter in the occipital lobes. Two of the nine patients also had similar findings in the cerebellum and frontal lobes.

The findings on the CT and MR studies resolved on follow-up examinations performed after the hypertension was corrected.

Our results suggest that the radiological findings associated with hypertensive encephalopathy in the appropriate clinical setting are very useful to achieve an early diagnosis.

Viabilidade de duas novas técnicas para inseminação intrauterina laparoscópica em ovinos

Avaliaram-se duas novas técnicas de inseminação laparoscópica intrauterina com o uso de agulha espinhal em ovinos. Foram realizadas quatro etapas experimentais, sendo os animais separados em dois grupos em cada etapa. Para tanto, foram utilizados os posicionamentos quadrupedal e dorsal. Realizou-se a inseminação de 80 ovinos após a sincronização de cio. Verificou-se que os acessos laparoscópicos propostos foram viáveis para a inseminação em ovinos. Considerou-se que a inseminação em posicionamento quadrupedal foi tecnicamente mais difícil se comparada ao acesso laparoscópico em decúbito dorsal, porém, com o aprimoramento da técnica e na dependência dos resultados quanto aos índices de prenhez, poderá se tornar procedimento adequado para a inseminação de ovelhas.

Season of the year influences testosterone secretion in bulls administered luteinizing honrmone

The objective of the present study was to evaluate the secretion of testosterone (T) in bulls in response to the administration of varying doses of bovine LH (bLH) during the four seasons of the year. Five adult bulls (4 yr of age) were treated with an amount of bLH that was estimated to induce a 5 ng/mL amplitude pulse of LH in blood serum on five consecutive days around the spring equinox, summer solstice, fall equinox, and winter solstice. Five hours after this dose, bulls were treated with bLH in amounts that were estimated to induce a 0.25, 0.5, 1, 2, or 4 ng/mL amplitude LH pulse in blood serum in a Latin square design. Blood samples were collected for 5 h after administration of a dose of bLH that was estimated to induce the 5-ng amplitude LH pulse, and for 3 h after administration of the variable doses of bLH, and were then assayed for concentrations of T. Average concentrations and amplitude of T release after doses of bLH that were estimated to induce the 5-ng amplitude LH pulses were greater during the spring and summer than during the winter (P < 0.05). The area under the release curve (AUC) was greater during the spring than during the winter (P < 0.05). During the 3 h after treatment with the variable doses of bLH, T response was affected by dose (P < 0.001) and season (P < 0.001), but there was no dose x season interaction. Testosterone response increased in a dose-dependent fashion for all variables studied. The greatest average concentrations of T and AUC were observed in the spring compared with the fall and winter (P < 0.05). These data support our working hypothesis that testes of bulls are more responsive in releasing T in response to bLH stimulation in the spring and summer compared with the winter; however, there were no changes in sensitivity of the testes to LH during different seasons of the year as indicated by the lack of a dose of bLH x season interaction.

Correlation of Tc-99m-red blood cell phleboscintigraphy with clinical severity of chronic venous disease

Equilibrium red blood cell phleboscintigraphy of the lower limbs for the diagnostic management of chronic venous disease has been proposed. The aim of this study was to verify the correlation of the phleboscintigraphic assessment of chronic venous disease with the clinical grading of the severity of the disease, since other diagnostic modalities have been recently demonstrated a poor and only partial correlation. Equilibrium Tc-99m-red blood cell phleboscintigraphy was performed in 27 patients with chronic venous disease. Scintigraphic images of 52 limbs were classified according to a four-class qualitative grading of the severity of the venous disease, and a quantitative scintigraphic index (saphena /femoral ratio) was assigned to each limb. The scintigraphic qualitative grading showed a highly significant correlation with the clinical grading (Rs=0.82, p<0.01), a good interobserver and intraobserver agreement (86.5% and 92.3%, respectively) and more than 90% sensitivity and specificity to identify the categories "minimal or no chronic venous disease" or "more significant disease" (assessed according to the Bayes theorem). Sensitivity and specificity results for the quantitative assessment were not as good. Phleboscintigraphy correlates well with the clinical grading of the severity of chronic venous disease of the lower limbs and may have potential as a valuable diagnostic tool for the noninvasive assessment of chronic venous disease.

Hyperthyroidism with concurrent thyroid cancer

The occurrence of thyroid malignancy is considered a rare event in hyperthyroid patients. With the aim of assessing the clinical relevance of this association, we have analyzed the incidence of thyroid cancer in hyperthyroid patients treated by surgery. The incidence of thyroid cancer was retrospectively evaluated in 202 hyperthyroid patients who underwent thyroidectomy during a twenty-year period. A thyroid cancer was diagnosed in 12 cases (5.9 per cent). Histologic examination revealed the presence of papillary carcinoma in 9 cases, follicular carcinoma in 1 case and Hürthle cell carcinoma in 2 cases. The association between thyroid cancer and hyperthyroidism was more frequent in toxic adenomas (17.8 per cent) than in toxic diffuse (5.3 per cent) or multinodular goiters (1.7 per cent). In 8 patients they presented as an occult carcinoma (maximum diameter below 1 cm), but unfavourable histologic features, such as local invasiveness and multifocality, were found in 5 of them. Follow-up data indicate that all 12 patients are currently alive and apparently free of disease. Hyperthyroid patients, particularly those affected by toxic adenomas, should be carefully evaluated to exclude the presence of concurrent malignancy. A special attention should be made moreover to the presence of "occult" lesions that, in our study was characterized in a higher proportion (62.5 per cent) of cases, by unfavourable histologic features.

A multicenter randomized trial of prophylaxis with intravenous cefepime + metronidazole or ceftriaxone + metronidazole in colorectal surgery. The 230 Study Group

We compared two prophylactic antimicrobial regimens in 615 patients undergoing elective colorectal surgical procedures. Patients ranged in age from 19 to 92 years (median 66 years); the majority were male (54.0%) and most (77.7%) had neoplastic disease. All underwent mechanical bowel preparation. Patients were randomized to receive preoperative infusions of 2 g cefepime (n=307) or 2 g ceftriaxone (n=308), followed by 500 mg metronidazole. Patients were followed for up to 4 to 6 weeks after surgery. Antimicrobial prophylaxis was successful in preventing primary site infections in 92.8% of patients in the cefepime + metronidazole arm and 92.9% of patients in the ceftriaxone + metronidazole arm. Both regimens were well tolerated. A single dose of cefepime + metronidazole thus seems to be a very useful alternative to other regimens for prophylaxis in patients undergoing colorectal surgery.

Corpus luteum development and function in cattle with episodic release of luteinizing hormone pulses inhibited in the follicular and early luteal phases of the estrous cycle

The influence of episodic LH pulses before and subsequent to ovulation on size and function of the corpus luteum (CL) in cattle was examined. Treatments were 1) control; 2) LHRH antagonist starting 2 days before the preovulatory LH surge (Antagonist [Ant] -2); 3) LHRH antagonist at initiation of the preovulatory LH surge (Ant 0); and 4) LHRH antagonist starting 2 days after the preovulatory LH surge (Ant 2). Treatments with an LHRH antagonist were continued until 7 days after the preovulatory surge. Diameter of the CL and concentrations of progesterone were monitored during the luteal phase that ensued after treatment. Maximum average diameters of CL were 9.5, 17.5, 21.6, and 28.8 mm for females from the Ant -2, Ant 0, Ant 2, and control groups, respectively (P < 0. 01). Compared with those in control animals, concentrations of progesterone in plasma were less (P < 0.01) in animals in which release of LH pulses was inhibited by treatment with antagonist. Arbitrary units under the curve for concentrations of progesterone during the luteal phase of the estrous cycle for Ant -2, Ant 0, Ant 2, and control groups were 19.6, 41.6, 43.6, and 142.2, respectively. There was no difference in circulating concentrations of progesterone (P > 0.1) among antagonist-treated groups. In conclusion, episodic release of LH pulses before, during, and after the time of the preovulatory surge of LH may stimulate development and function of the CL in cattle.

[The histopathological and microbiological aspects in a model of acute acalculous cholecystitis: an experimental study]

The early stages of acute acalculous cholecystitis (ACC) have been difficult to investigate due to the animal models developed and utilized over the past years. A new model of animal AAC induced by intra-abdominal sepsis is presented. Under general anesthesia 35 guinea pigs underwent laparotomy. The designed model included ligation and prick of the caecum in 25 animals (group A), while 10 animals served as control group (group B). Seven days after these experimental procedures animals underwent relaparotomy and were submitted to cholecystectomy and sacrifice. Histological studies of the specimen revealed various degrees of cholecystitis in all the gallbladders of survived animals from group A. Gallbladders of animals from group B were histologically normal. Gallbladder bile of 15 survived animals from group A were cultured. Bile cultures were negative in 10, while culture of gallbladder bile were positive in 5; the pathogen cultured were Streptococcus Faecalis and Streptococcus Sp. The results of this study suggest that intra-abdominal sepsis induces gallbladder inflammation of various degrees. This directly supports the theoretical relationship indicating that sepsis and shock could produce AAC. Moreover this model proved that AAC, in early stages, is primarily induced by inflammatory processes, while infection of the bile do represent a late event.

Circulating concentrations of estradiol, luteinizing hormone, and follicle-stimulating hormone during waves of ovarian follicular development in prepubertal cattle

Objectives were to characterize changes in concentrations of LH, FSH, and estradiol-17beta (estradiol) in blood and populations of ovarian follicles of prepubertal cattle during waves of follicular development and to evaluate interactions between day after follicular aspiration and month prepuberty for these variables. During each month (month prepuberty), ovarian follicles of prepubertal cattle were aspirated to induce synchronous emergence of a wave of follicular development (day after follicular aspiration). Characteristics of ovarian follicular development and concentrations of hormones in blood were evaluated during the synchronous wave of follicular growth. Multiple regression was used to estimate hormonal variables and evaluate interactions for variables between day after follicular aspiration and month prepuberty. There were no interactions between day after follicular aspiration and month prepuberty for numbers of follicles </= 4 or > 5 mm or concentrations of LH, FSH, and estradiol. The pattern of change in these variables after follicular aspiration was, therefore, similar each month prepuberty. There were interactions between day after follicular aspiration and month prepuberty for frequency and amplitude of LH pulses and size of largest follicle. There were also endocrine changes that were related to follicular development after follicular aspiration throughout the peripubertal period.

Testicular morphology and function in boars differing in concentrations of plasma follicle-stimulating hormone

The objective of this study was to evaluate morphological characteristics and testicular function of boars with different endogenous concentrations of FSH. Boars were selected at 6 mo of age on the basis of mean FSH concentrations in plasma collected at 4, 5, and 6 mo of age. Boars were classified within half-sibling families based on whether they had high concentrations of FSH (HiFSH, > 500 ng/ml, n = 9) or low concentrations (LoFSH, < 500 ng/ml, n = 7). At 14.5 mo, testes were collected, fixed, sectioned at 1 microm, and evaluated for morphological characteristics. Boars with LoFSH had larger (p < 0.01) testicular and epididymal weights than boars with HiFSH, greater (p < 0.01) daily sperm production per gram of testis, and greater total daily sperm production per boar. Testes of boars with LoFSH had a greater (p < 0.03) volume percentage of seminiferous tubules, a lesser percentage (p < 0.03) of Leydig cells, and a somewhat lesser (p = 0.06) percentage of vascular structures than testes of boars with HiFSH. Testes of boars with LoFSH had greater (p < 0.01) total tubule volume and tubule length than testes of boars with HiFSH. There were no differences (p > 0.70) in volume, diameter, or total number of Leydig cells or in total interstitial volume in testes (p > 0.41) of these two groups. Production of testosterone in vitro per paired testis and per million Leydig cells was not different (p > 0.65) between boars with HiFSH or LoFSH. Greater concentrations of FSH in blood plasma were negatively associated with development of seminiferous tubules and spermatogenic efficiency, whereas Leydig cell development was not different in boars of these two groups.

Prevalence of thyroid cancer in hyperthyroid patients treated by surgery

A retrospective study has been carried out to evaluate the prevalence of malignant thyroid tumors in 202 patients submitted to surgery for hyperthyroidism. Thyroid cancer was diagnosed in 12 cases (5.9%); the final histologic examination revealed nine papillary carcinomas, one follicular carcinoma, and two Hürthle cell carcinomas. Concurrence of hyperthyroidism and thyroid cancer was more frequent in patients with single toxic adenomas than in those with toxic diffuse or multinodular goiters. In five cases thyroid malignancy was detected in the context of the hyperthyroid lesion (three toxic adenomas and two diffuse goiters). In eight patients the malignant lesion showed a maximum diameter of less than 1 cm, although in five of these cases unfavorable histologic features, such as minimal capsular invasion or multifocality, were present. All patients presenting with thyroid cancer are currently alive and apparently free of residual disease. It is concluded that hyperthyroid patients, particularly those with single toxic adenomas, should be carefully evaluated to exclude the presence of an associated malignancy and to plan the most appropriate therapeutic options.

Radionuclide venography and the surgical treatment of chronic venous disease of the lower extremity

PURPOSE

The purpose of this study was to describe the use of radionuclide venography in detecting the site and the functional value of blood reflux through incompetent perforating veins of the leg of patients with chronic venous disease.

METHODS

In this study we evaluated the management of 29 patients (34 lower limbs) who were admitted with chronic venous disease of the lower limbs (in 7 with ulcers refractory to conservative management), surgically treated between 1991 and 1994 on the basis of physical examination and scintigraphic detection of pathological venous refluxes.

RESULTS

In 26/29 patients (31/34 legs = 91%) there was a good result with no recurrence and complete alleviation of symptoms. All the ulcers healed but in two cases recurred after 2 and 6 months respectively. Amelioration of leg tropism was achieved in all patients with a good "cosmetic" result in 27/34 legs (79%). A complete deconnection of the incompetent perforating veins was confirmed with radionuclide venography in 31/34 legs (91%).

CONCLUSIONS

The authors conclude that radionuclide venography is useful in the pre-operative evaluation of patients with chronic venous disease of lower extremity.

Analysis of adenomatous polyposis coli gene in thyroid tumours

Familial adenomatous polyposis (FAP) is known to be associated with neoplasia of various tissues, including thyroid carcinoma. Germline mutations of the tumour-suppressor gene APC, responsible for the predisposition to FAP, may therefore be involved in the pathogenesis of these tumours. In this report the structure of the APC gene has been investigated in 26 thyroid tumours, at different stages of dedifferentiation, that were surgically excised from patients with a negative history of FAP. Approximately 35% of the APC gene coding region, where most of the mutations are clustered, has been analysed by a combination of single-strand conformation polymorphism and direct sequencing. No significant alterations could be demonstrated in any sample examined. It is concluded that, at least in patients not affected by FAP, APC gene abnormalities do not seem to play a relevant role in the pathogenesis of thyroid carcinoma.

[Surgical therapy of the autonomous thyroid nodule]

Indications for the surgical removal of autonomous nodule are mainly based upon the failure of therapeutical options. The histological definition may be advantageous for detecting the rare but possible association between autonomous goiter and carcinoma of the thyroid. In personal experience, based on 176 hyperfunctioning goiter (among which there were 40 cases of autonomous nodules) 6 carcinomas of the gland were observed, 2 of these were associated with autonomous nodules. The extension of thyroidectomy is related to the size of the adenomas considering the incidence of postoperative complications, very low for this type of surgery. Surgical treatment of autonomous nodules of the thyroid is a low risk surgery and is therefore suitable for the treatment of this disease.

Estrogen and progesterone receptors in the gallbladders from patients with gallstones

Cytosolic receptors for estrogen and progesterone were assayed in 50 gallbladders from 29 women and 21 men who had cholecystectomies because of cholelithiasis. High-affinity (equilibrium dissociation constant, KD = 0.46 +/- 0.23 nmol/L of 24 cases) estrogen receptors were detected in 20 of 29 gallbladders from women (range = 1.6 to 32 fmol/mg protein; mean +/- S.D. = 10.9 +/- 8.1), whereas in men only 4 of 21 specimens contained detectable estrogen receptors. High-affinity (KD = 0.45 +/- 0.17 nmol/L; mean +/- S.D. of 41 cases) progesterone receptors were found in 25 of 29 gallbladders of women (range = 2 to 62 fmol/mg protein; mean +/- S.D. = 19.2 +/- 14.4) and in 16 of 21 gallbladders of men (range = 4 to 36 fmol/mg protein; mean +/- S.D. = 12.5 +/- 8.5). There is a statistically significant difference between men and women in the proportion of estrogen receptor-positive gallbladders, 19% and 69% for men and women, respectively. Progesterone receptors are present in similar proportion in the gallbladders of men (72.2%) and women (86.2%). In women a positive correlation between estrogen and progesterone receptors was found. Even in the absence of estrogen receptors, the gallbladders of men express progesterone receptors at levels similar to those observed in women. At least in cholelithiasic gallbladders, this suggests that a sex difference exists in the coexpression of estrogen and progesterone receptors. Such a difference could be related with the higher gallstone incidence in women than in men.

Aztreonam biliary excretion in bile duct ligated jaundiced rats

An experimental study was undertaken to assess aztreonam biliary concentrations in bile duct ligated jaundiced rats. The study proved that aztreonam biliary concentrations are sufficient to inhibit Gram-negative bacteria within the first and the second hour after antibiotic administration. The experimental model suggests that clinical conditions such as lithiasis or neoplasms of the biliary tree should not totally inhibit the antibiotic excretion.

Physiopathologic role of microlithiasis in gallstone pancreatitis

A study of 108 patients with acute or acute relapsing gallstone pancreatitis was carried out in order to evaluate the incidence of biliary lithiasis and microlithiasis. The severity of pancreatic damage associated with both clinical states and the physicochemical characteristics of the minute stones were also evaluated. The results suggest that the risk of acute pancreatitis is increased in patients with microlithiasis and that in patients with acute pancreatitis due to microlithiasis the lesions are more severe. These results warrant the conclusion that cholecystectomy should be performed upon all patients with echographically detected microlithiasis, even in the absence of symptoms. Early surgical treatment must be performed whenever pancreatitis develops.

Hormonal studies in a patient with PP-producing tumors

Five years after the removal of pure pancreatic polypeptide (PP) producing tumors, concentrations of circulating levels of PP, insulin, glucagon, and growth hormone in the basal state, after insulin-induced hypoglycemia, and after a protein-rich meal were determined in a patient with previous truncal vagotomy and Billroth II gastrectomy. Basal plasma levels of PP ranged between 2180 and 2660 pg/ml suggesting persistence or recurrence of PP producing tumors. Concentrations of the other hormones were within normal values. After insulin injection (0.1 U/Kg) levels of PP and glucagon were not modified while those of GH rose from 3.2 to 22.6 ng/ml. After a protein meal (450 gms. of cooked ground beef meat) a sharp rise of plasma PP was observed to a peak of 11310 pg/ml at 10 min. Moreover, plasma levels of immunoreactive insulin also showed an equally prompt rise to a peak of 532 microU/ml while plasma glucagon rose simultaneously to 448 pg/ml. The cause of the abnormal PP, insulin and glucagon responses could not be ascertained but we postulate that they are derived from pancreatic tumors of mixed cell type.

Dose-response study with indoprofen i.v. as an analgesic in postoperative pain

A double-blind, placebo-controlled parallel-group study was carried out in 100 patients with postoperative pain. The analgesic activity of indoprofen given in a single dose as an i.v. bolus followed by a 2-h infusion, at total doses of 100, 200, and 400 mg was investigated. The highest dose of 400 mg was given additionally as an i.v. bolus alone. Intensity of pain was assessed before, and 30 min, 1, 2, 4, 6 and 8 h after treatment on a 0-4 point scale. An overall assessment was made at the end of treatment by the investigator and the patient using a 0-4 point scale and a visual analogue scale. Statistical analyses according to a multiple regression model on rating scale scores at fixed times and on overall assessments showed: (i) indoprofen was always more active than placebo in providing pain relief; (ii) there was a significant dose--response relationship; and (iii) there was no difference between the two schedules of administration of the largest dose.

Prolactin secretion and nodular goiter. (Hypothetical correlations)

In a group of 129 female patients with nodular goiter, Graves' disease and primary hypothyroidism, the PRL and TSH secretions were studied in parallel. Concurrent changes in the two hormones were evident only in conditions of marked hyper- or hypothyroidism. In the patients with non-toxic nodular (single or multiple) goiter the TSH showed low or normal values, while the PRL appeared normal or elevated. From these results two important conclusions can be drawn: 1. the T3 and T4 levels interact with PRL secretion concomitantly with TSH only when they undergo a huge deviation from the normal range; 2. the goitrogenic action of PRL that has been reported in experimental animals cannot be excluded in man.