Electrophysiological evidence that circulating angiotensin II sensitive neurons in the subfornical organ alter the activity of hypothalamic paraventricular neurohypophyseal neurons in the rat

Electrical stimulation of the rat A1 noradrenergic region produced excitation (77%) of the activity of putative vasopressin (VP)-secreting neurons in the paraventricular nucleus (PVN) and produced excitation (4%), inhibition (26%) and excitation-inhibition (11%) of the activity of PVN neurons that were not antidromically identified by neurohypophysial stimulation. The excitatory response of putative VP-secreting neurons was blocked by microiontophoretically applied phentolamine, an α-adrenoceptor antagonist, but not by timolol, a β-adrenoceptor antagonist. The inhibitory response of unidentified PVN neurons, on the other hand, was blocked by timolol, but not by phentolamine.     

Plasma membrane structures of medulloblastoma and cerebellar sarcoma

Three medulloblastomas and 1 cerebellar sarcoma were studied on their plasma membrane structures. The average number of membrane particles per mum2 plasma membrane was 710 on face A and 70 on face B of medulloblastoma and 1280 on face A and 160 on face B of cerebellar sarcoma. The membrane particles were often aggregated in medulloblastoma and diffusely scattered in cerebellar sarcoma. Small gap junctions were occasionally found in cerebellar sarcoma and not evident in medulloblastoma. Round membrane protrusions, about 0.5-0.6 mu in diameter and provided with several small depressions on their foot, were often observed in region of narrow perinuclear cytoplasm of cerebellar sarcoma and different in structure from cytoplasmic processes. The present series is too limited in number to allow a definite conclusion, but indicates that the plasma membrane structures are different in medulloblastoma and cerebellar sarcoma.     

Antispasmodic activity of extracts from plants used as anti-diarrhea preparations in Kinshasa, Za?re

A preliminary and anterior pharmacological study about 68 plant antidiarrheic traditional preparations, has proved the antispasmodic activity for 42 of them. Some extracts proceeding of these possess an antispasmodic activity, specially if they contain polyphenols (flavono?ds, catechics tanins), saponins and alkalo?ds.     

Blockade or reversal of the contraction induced by calcium and adrenaline in depolarized arterial smooth muscle

1. Mesenteric arteries immersed in a depolarizing solution contract in the presence of calcium. These contractions are proportional to the calcium concentration and are reversible.2. Mesenteric arteries immersed in a calcium-free depolarizing solution contract in the presence of adrenaline. Under the experimental conditions reported here, this response develops only about one-third of the contractile tension developed in polarizing solution (modified Krebs bicarbonate).3. Cinnarizine and chlorpromazine inhibit the contractile response to calcium and induce relaxation of depolarized muscle previously contracted by calcium; cinnarizine was 4 times more potent than chlorpromazine in such activity.4. Chlorpromazine inhibits the response to adrenaline in both polarizing and calcium-free depolarizing solutions, whereas cinnarizine inhibits the response in polarizing solution but not that in calcium-free depolarizing solution.5. The significance of these results is discussed.     

Nationwide HIV prevalence survey in general population in Niger

A national population-based survey was carried out in Niger in 2002 to assess HIV prevalence in the population aged 15-49 years. A two-stage cluster sampling was used and the blood specimens were collected on filter paper and tested according to an algorithm involving up to three diagnostic tests whenever appropriate. Testing was unlinked and anonymous. The refusal rate was 1.1% and 6056 blood samples were available for analysis. The adjusted prevalence of HIV was 0.87% (95% CI, 0.5-1.3%) and the 95% CI of the estimated number of infected individuals was 22 864-59 640. HIV-1 and HIV-2 represented, respectively, 95.6% and 2.9% of infections while dual infections represented 1.5%. HIV positivity rate was 1.0% in women and 0.7% in men. It was significantly higher among urban populations than among rural ones (respectively, 2.1% and 0.6%, P < 10(-6)). Using logistic regression, the variables significantly related to the risk of being tested positive for HIV were urban housing, increasing age and being either widowed or divorced. The estimate from the national survey was lower than the prevalence assessed from antenatal clinic data (2.8% in 2001). In the future, the representativeness of sentinel sites should be improved by increasing the representation of rural areas accounting for more than 80% of the population. Compared with other sub-Saharan countries, the HIV prevalence in Niger is still moderate. This situation represents a strong argument for enhancing prevention programmes and makes realistic the projects promoting an access to potent antiretroviral therapies for the majority.     

The azygos lobe: an unusual anatomical observation with pathological and surgical implications

The azygos lobe is a rare anomaly in broncho-pulmonary segmentation due to an unusual course of the azygos vein. Its radiological aspects are well known but there are few anatomical reports about its bronchial and vascular components. The authors describe the characteristic features in a particular case of the azygos lobe observed in the right lung after studying a fresh specimen and doing a casting of said specimen. This azygos lobe was in a position medial to the right upper lobe and above the hilum. It had the shape of an egg and was 5 cm high, 4 cm wide and 2 cm thick. The azygos fissure was of a vertical form. The lobe was ventilated by the posterior branch of the apical segmental bronchus (B1a). This latter was accompanied by two apical sub-segmental arteries (A1ai, A1aii) and the apical intersubsegmental vein (V1a). The new findings were that: first, the azygos lobe bronchus supplied a part of the right upper lobe; second, the passage of the azygos vein deformed the bronchus of the right upper lobe, and not that of the azygos lobe. This means that it was the right upper lobe, rather than the azygos lobe that was predisposed to the pathology. So, in excising this type of azygos lobe, particular precautions have to be taken to spare the bronchus of the azygos lobe that supplies the right upper lobe.     

Intermittent preventive treatment using artemisinin-based combination therapy reduces malaria morbidity among school-aged children in Mali

Objective  To assess the efficacy of intermittent preventive treatment (IPT) against malaria in school-aged children.
Methods  This was an open randomized controlled trial of seasonal IPT among school children (IPTsc) aged 6–13 years in Kollé, Mali. The study began in September 2007 and completed follow-up in May 2008. Students were randomized to one of three study arms: Sulfadoxine–pyrimethamine plus artesunate (SP/AS), amodiaquine plus artesunate (AQ/AS) or vitamin C. All students received two full treatment doses, given 2 months apart during the season of high transmission from September to December. Groups were compared with respect to incidence of clinical malaria, asymptomatic parasitemia and haemoglobin concentration.
Results  A total of 296 students were randomized, and retention in the study was 99.3%. Clinical malaria incidence in the SP/AS and AQ/AS arms was reduced by 66.6% and 46.5%, respectively, vs . vitamin C ( P  < 0.001). There were fewer clinic visits for any cause among the children receiving SP/AS or AQ/AS ( P  = 0.024). The prevalence of asymptomatic parasitemia was fivefold higher in the vitamin C arm than either SP/AS or AQ/AS at each post-treatment evaluation ( P  < 0.001). At the end of the transmission period, children treated with IPT had lower rates of anaemia (SP/AS, 17.7%; AQ/AS, 16.0%; vitamin C, 29.6%; P  = 0.039).
Conclusion  IPT among school children reduced the rates of clinical malaria, all-cause acute clinic visits, asymptomatic parasitemia and anaemia among school-aged children.     

Functional synapse formation between cultured rat accessory olfactory bulb neurons and vomeronasal pockets

To investigate the interaction between vomeronasal receptor neurons and accessory olfactory bulb neurons during pheromonal signal processing and specific synapse formation, partially dissociated rat vomeronasal receptor neurons were co-cultured with accessory olfactory bulb neurons. Between 7 and 14 days in co-culture, a few bundles of fibers from a spherical structure, termed the vomeronasal pocket, of cultured vomeronasal receptor neurons extended to the accessory olfactory bulb neurons. An optical recording of the intracellular Ca(2+) concentration was used to monitor the synaptic activation of cultured accessory olfactory bulb neurons. Electrical stimulation of the vomeronasal pocket between 7 and 14 days in co-culture had no effects on most of the cultured neurons tested, although it occasionally evoked weak responses in a small number of neurons. In contrast, vomeronasal pocket stimulation after 21 days in co-culture evoked clear calcium transients in a substantial number of cultured accessory olfactory bulb neurons. These responses of accessory olfactory bulb neurons were reversibly suppressed by the application of 6-cyano-7-nitroquinoxaline-2,3-dione; the calcium transients disappeared in most of the neurons and were diminished in the others. The application of d-2-amino-5-phosphonopentanoic acid partially affected the calcium transients, but blocked spontaneous calcium increases, which were observed repeatedly in accessory olfactory bulb-alone cultures. The application of both 6-cyano-7-nitroquinoxaline-2,3-dione and d-2-amino-5-phosphonopentanoic acid completely blocked the evoked calcium transients. These results suggest that functional glutamatergic synapses between vomeronasal receptor neurons and accessory olfactory bulb neurons were formed at around 21 days in co-culture.     

Arteriography of three models of gastric oesophagoplasty: the whole stomach, a wide gastric tube and a narrow gastric tube

The esogastric anastomotic fistula,occurring after the replacement of esophagus by the stomach, is a post-operative complication always feared and awaited. Apart from other causes, there exist the anatomical dispositions notably the vascular and technical factors that stress this potential risk despite certain advantages of esophagogastroplasty. The goal of our study was to study the arterial distribution of the gastric transplants in order to identify the better modalities of their making. We used 39 stomachs taken from fresh cadavers of autochtone subjects. After a modeling treatment using three different techniques, they were subjected to a radiographic opacification of the right gastro-epiploic artery with sulphate of barium follow by an x-rays in incidence full-face (25 kv, 10 mAS). It was a matter of 15 entire stomachs (E.E.) with denudation of the small curvature, of 12 wide gastric tubes (W.T.) prepared according to the Akiyama technique modified and of 12 narrow tubes (N.T.) tubulized according to the Marmuse method. We studied the anastomotic type of the gastro-epiploic arterial circle according to the classification of Koskas, the collateral branches of the arterial circles of the gastric curvatures, the antral and corporeal anastomosis of these circles and the distribution anastomotic at the level of the summit of the anastomotic. Only 28 pieces (15 E.E., 8 W.T. and 5 N.T.) were able to be the object of a complete angiographic exploitation. The anastomosis of the arterial circle was type I in 64.1% of the cases, type II in 15.4% of the cases, type III in 15.4% of the cases and type IV in 5.1% of the cases. The average number of collateral branches originating from gastro-epiploic arterial circle was respectively 24, 17 and 22 for the E.E., the W.T. and the N.T. Only the two first ones presented collateral branches being borne of the small curvature circle. Fifty per cent of the N.T. did not possess any antral or corporeal anastomosis between the two arterial circles; some of them were even for a quarter of the W.T. In the case of gastric tubulization there existed an irrigation defect of the summit of the plasty for a third of the N.T. and a quarter of the W.T., despite a constant intramural bridge anastomosis between the two gastro-epiploic arteries. The usage of the entire stomach must be recommended for gastric oesophagoplasty; but when the operative indications require a resection of the small curvature it is preferable to use a wide gastric tube whose diameter respects the two left third of the initial width of the organ.     

Microsurgical anatomy of intralaryngeal distribution of the inferior laryngeal nerve

The functional results of a partial laryngeal surgery or a laryngeal reinnervation depend on the precise knowledge of the intra laryngeal anatomy of the inferior laryngeal nerve (ILN). Ten human larynges without known laryngeal disorders were obtained from human cadavers for ILN microdissection. Intra laryngeal ILN branching patterns were determined bilaterally. The lengths of the vertical, genu and oblique segments of the anterior division of ILN and the distance between the nerve within the paraglottic space and the cricothyroid articulation (CTA) were measured with a digital microcaliper. The mean lengths of the vertical, genu and oblique segments were 10.82, 5.89 and 9.29 mm, respectively. The mean distance between the nerve in the paraglottic space and the CTA was 11.20 mm. Key anatomical landmarks of the abductor division (vertical and genu segments of ILN) were the lateral border of posterior cricoarytenoid (PCA) muscle and the superior ligament of the CTA. The two-branch pattern for the lateral border of the PCA muscle has been the most frequent (50%). A branch of interarytenoid muscle (IA) originated from the genu segment. One or two branches for the PCA muscle has been identified in 75% of cases from the IA neural plexus on the front side of PCA muscle. The adductor division for the thyroarytenoid muscle and the lateral cricoarytenoid muscle was the oblique segment of the nerve. We conclude that abductor and adductor divisions of intra laryngeal ILN can be readily identified and the knowledge of key landmarks allows preservation of the ILN during partial surgery of the larynx and possibly selective muscle reinnervation.