Circadian rhythm of glucose utilization in the pineal body of rats of different ages

Employing quantitative autoradiography, pineal body glucose utilization (GU) was measured in daytime or at night in prepubertal (aged 1 month), adult (aged 3 months), and mature (over 12 months old) rats. In prepubertal and adult rats, in daytime, GU values within the pineal tissue were homogeneously distributed around 65 mol glucose/100 g per min. In prepubertal animals no significant variations in GU were observed between daytime and nocturnal measurements. A circadian metabolic rhythmicity was evident in adult rats, with a GU peak measured at 2 a.m. In mature animals, GU also varied between day and night, with an increment in the relative difference between the two values. The present investigation is the first to demonstrate that circadian metabolic rhythmicity is absent before sexual maturation while it is enhanced in 12-month-old rats. These changes in pineal energy metabolism with advancing age are intriguing in view of the concept that the pineal gland may be involved in functional changes occurring during the process of aging.     

Paradoxical stimulation of prolactin secretion by L-dopa in metastatic prostate cancer and its possible role in prostate-cancer-related hyperprolactinemia

OBJECTIVE: In addition to sex steroids, prolactin (PRL) may also stimulate prostate cancer growth. Abnormally high blood levels of PRL have been noted in metastatic prostate cancer patients. However, most studies have been limited to the evaluation of basal levels of PRL rather than to investigate its secretion in response to classical endocrine dynamic tests. This study was carried out to analyze PRL secretion in metastatic prostate cancer patients both at basal conditions and in response to L-Dopa and metoclopramide, which represents the most classical inhibitory and stimulatory tests for PRL secretion, respectively. METHODS: The study included 12 patients with metastatic prostate cancer. On separate occasions, PRL secretion was evaluated in response to L-Dopa (500 mg orally) and to metoclopramide (10 mg i.v. as a bolus). Serum levels of PRL were measured by RIA. RESULTS: Mean PRL concentrations significantly increased after metoclopramide administration, even though no PRL response occurred in 6 of 12 patients. L-Dopa was unable to reduce PRL levels, which, in contrast, paradoxically significantly increased in response to L-Dopa, with mean values comparable to those achieved after metoclopramide injection. CONCLUSION: By showing a paradoxical stimulatory effect of L-Dopa on PRL secretion and a lack of response to metoclopramide in some patients, this study would suggest the existence of evident alterations in the neuroendocrine regulation of PRL release in advanced prostate cancer.     

Assessment of efficacy of bothropic antivenom therapy on microcirculatory effects induced by Bothrops jararaca snake venom.

Intravenous administration of antibothropic antivenom (BAv) neutralises the systemic effects, but does not efficiently reverse the local symptoms elicited by the Bothrops jararaca venom (BjV). The mechanisms involved in this poor protection have not been clarified. In this work, intravital microscopy studies were carried out to determine the efficacy of different schedules of BAv treatment on local effects evoked by topical application of BjV in the microcirculatory network of the internal spermatic fascia of Wistar rats. Results demonstrated that BAv administration 15 min before, simultaneously with, or 15 min after BjV application did not totally reverse the local symptoms, represented by disturbances of coagulation, development of haemorrhage lesions, vascular permeability increase and increment on leukocyte-endothelium interactions. This lack of effectiveness neither reflects an inadequate amount of specific antibodies in the antivenom against toxins responsible for local effects nor an insufficient dose of circulating BAv during the assays. Administration of fluorescein isothiocyanate (FITC) labelled-BAv showed the dynamics of distribution of the antivenom in the microcirculatory network. Images obtained from prior and simultaneously treated animals showed that the antivenom remains at luminal side of vessels before venom application, and the latency time to antivenom leakage is coincidental to that for local effects evoked by the venom. In addition, images from posterior treatment demonstrated that the intense alterations in the microcirculatory network impair antivenom distribution at the site of injection. Together, our data show that the lack of effectiveness of antivenom therapy is due to impaired and delayed venom and antivenom interaction at the site of injury.     

Prevalence of faecal incontinence among women with urinary incontinence

Four hundred and sixty-five women attending a urodynamic clinic were interviewed, and completed a detailed bowel questionnaire, about their urinary and bowel symptoms. All the women underwent video-cystourethrography with pressure and flow studies. The reported incidence of faecal incontinence was 15.3% (   n = 71  ) on direct questioning and 26% 0(  n = 121  ) on the postal questionnaire. Faecal incontinence was more common in women with a urodynamic diagnosis of detrusor instability (30'%1 (   n = 26  )) than among women diagnosed as having genuine stress incontinence (21% (   n = 38  )). Denervation and myogenic injuries sustained during childbirth have been suggested as a common cause for genuine stress and faecal incontinence, but there may be an alternative mechanism to explain why women with detrusor instability suffer from faecal incontinence.     

Management of the internal carotid artery in tumors of the lateral skull base: preoperative permanent balloon occlusion without reconstruction.

OBJECTIVE: To present our experience with permanent preoperative balloon occlusion of the internal carotid artery while dealing with different abnormalities of the lateral skull base and a comparison with the results mentioned in the literature. STUDY DESIGN: Retrospective case review. SETTING: Private neurotologic and skull base tertiary referral center. PATIENTS: Fifteen patients who underwent preoperative balloon occlusion of the internal carotid artery and surgery subsequently for various abnormalities of the lateral skull base between 1989 and 2002. INTERVENTIONS: Each patient was subjected to four-vessel angiography along with the manual cross-compression test and balloon test occlusion to assess the efficacy of the collateral circulation. After angiography, each patient underwent a preoperative balloon occlusion, after which a lateral skull base procedure was performed for removal of the abnormality. MAIN OUTCOME MEASURES: Only those patients showing evidence of adequate collateral cerebral circulation and a less than 1-second delay between the angiographic phases of the two cerebral hemispheres on angiography were considered fit for preoperative balloon occlusion. While under going the preoperative balloon occlusion, the patients were clinically assessed for the development of any neurologic symptoms and signs. Long-term follow-up after surgery was also based on the development of symptoms and signs of neurovascular compromise. RESULTS: A major complication in the form of long-lasting hemiplegia occurred in one patient (6.7%). This complication was the result of technical factors rather than an effect of cerebral ischemia, because it was caused by an intimal dissection produced by the catheter. A defect in the visual field occurred in one patient (6.7%) that resolved partially after antiplatelet therapy. There was no mortality in our series related to preoperative balloon occlusion of the internal carotid artery. CONCLUSION: Preoperative balloon occlusion of the internal carotid artery can still be considered a viable option for the management of the internal carotid artery during lateral skull base surgery. Proper preoperative evaluation of the adequacy and efficacy of the collateral cerebral circulation reduces the chances of postoperative neurovascular complications.     

A case of mediastinal teratoma as a cause of nonimmune hydrops fetalis, and literature review

This article reviews the current literature of mediastinal tumors as the cause of nonimmune hydrops fetalis (NIHF), the outcomes of reported cases, and a general overview of NIHF including diagnosis, workup, and a management algorithm, with particular attention made to intrathoracic lesions and gestation age. We present a unique case report of a premature neonate who initially presented with NIHF at birth and was subsequently diagnosed with a germ cell mediastinal teratoma as the etiology of NIHF. The patient survived for 50 days while having undergone surgical resection and chemotherapy during the hospital course. The patient represents the first reported case of a mediastinal tumor as the etiology of NIHF in the neonatal period and only one of three cases that have been reported to survive in the neonatal period. Survival is dependent on the thoracic lesion's size, location, resectability, impact on the growth and development of other vital organs, and in the case of tumors, malignant potential. Though the combination of mediastinal teratoma and NIHF is rare, it should be included in the diagnostic evaluation of a newborn with NIHF.     

Gut–liver axis: The impact of gut microbiota on non alcoholic fatty liver disease

AimTo examine the impact of gut microbiota on non alcoholic fatty liver disease (NAFLD) pathogenesis.Data synthesisEmerging evidence suggests a strong interaction between gut microbiota and liver. Receiving approximately 70% of its blood supply from the intestine, the liver represents the first line of defence against gut-derived antigens. Intestinal bacteria play a key role in the maintenance of gut–liver axis health. Disturbances in the homeostasis between bacteria- and host-derived signals at the epithelial level lead to a break in intestinal barrier function and may foster “bacterial translocation”, defined as the migration of bacteria or bacterial products from the intestinal lumen to mesenteric lymph nodes or other extraintestinal organs and sites. While the full repertoire of gut-derived microbial products that reach the liver in health and disease has yet to be explored, the levels of bacterial lipopolysaccharide, a component of the outer membrane of Gram-negative bacteria, are increased in the portal and/or systemic circulation in several types of chronic liver diseases. Derangement of the gut flora, particularly small intestinal bacterial overgrowth, occurs in a large percentage (20–75%) of patients with chronic liver disease. In addition, evidence implicating the gut–liver axis in the pathogenesis of metabolic liver disorders has accumulated over the past ten years.ConclusionsComplex metabolic diseases are the product of multiple perturbations under the influence of triggering factors such as gut microbiota and diet, thus, modulation of the gut microbiota may represent a new way to treat or prevent NAFLD.