The challenges and opportunities of global neurosurgery in East Africa: the Neurosurgery Education and Development model

OBJECTIVE

The objective of this study was to describe the experience of a volunteering neurosurgeon during an 18-week stay at the Neurosurgery Education and Development (NED) Institute and to report the general situation regarding the development of neurosurgery in Zanzibar, identifying the challenges and opportunities and explaining the NED Foundation’s model for safe practice and sustainability.

METHODS

The NED Foundation deployed the volunteer neurosurgeon coordinator (NC) for an 18-week stay at the NED Institute at the Mnazi Mmoja Hospital, Stonetown, Zanzibar. The main roles of the NC were as follows: management of patients, reinforcement of weekly academic activities, coordination of international surgical camps, and identification of opportunities for improvement. The improvement opportunities were categorized as clinical, administrative, and sociocultural and were based on observations made by the NC as well as on interviews with local doctors, administrators, and government officials.

RESULTS

During the 18-week period, the NC visited 460 patients and performed 85 surgical procedures. Four surgical camps were coordinated on-site. Academic activities were conducted weekly. The most significant challenges encountered were an intense workload, deficient infrastructure, lack of self-confidence among local physicians, deficiencies in technical support and repairs of broken equipment, and lack of guidelines. Through a series of interviews, the sociocultural factors influencing the NED Foundation’s intervention were determined. Factors identified for success were the activity of neurosurgical societies in East Africa; structured pan-African neurosurgical training; the support of the Foundation for International Education in Neurological Surgery (FIENS) and the College of Surgeons of East, Central and Southern Africa (COSECSA); motivated personnel; and the Revolutionary Government of Zanzibar’s willingness to collaborate with the NED Foundation.

CONCLUSIONS

International collaboration programs should balance local challenges and opportunities in order to effectively promote the development of neurosurgery in East Africa. Support and endorsement should be sought to harness shared resources and experience. Determining the caregiving and educational objectives within the logistic, administrative, social, and cultural framework of the target hospital is paramount to success.

Neurosurgery in East Africa: Innovations

In the last 10 years, considerable work has been done to promote and improve neurosurgical care in East Africa with the development of national training programs, expansion of hospitals and creation of new institutions, and the foundation of epidemiologic and cost-effectiveness research. Many of the results have been accomplished through collaboration with partners from abroad. This article is the third in a series of articles that seek to provide readers with an understanding of the development of neurosurgery in East Africa (Foundations), the challenges that arise in providing neurosurgical care in developing countries (Challenges), and an overview of traditional and novel approaches to overcoming these challenges to improve healthcare in the region (Innovations). In this article, we describe the ongoing programs active in East Africa and their current priorities, and we outline lessons learned and what is required to create self-sustained neurosurgical service.

The degenerative cervical spine

Imaging techniques provide excellent anatomical images of the cervical spine. The choice to use one technique or another will depend on the clinical scenario and on the treatment options. Plain-film X-rays continue to be fundamental, because they make it possible to evaluate the alignment and bone changes; they are also useful for follow-up after treatment. The better contrast resolution provided by magnetic resonance imaging makes it possible to evaluate the soft tissues, including the intervertebral discs, ligaments, bone marrow, and spinal cord. The role of computed tomography in the study of degenerative disease has changed in recent years owing to its great spatial resolution and its capacity to depict osseous components. In this article, we will review the anatomy and biomechanical characteristics of the cervical spine, and then we provide a more detailed discussion of the degenerative diseases that can affect the cervical spine and their clinical management.

Neurosurgery Education and Development program to treat hydrocephalus and to develop neurosurgery in Africa using mobile neuroendoscopic training

OBJECT A shortage of neurosurgeons and a lack of knowledge of neuroendoscopic management of hydrocephalus limits modern care in sub-Saharan Africa. Hence, a mobile teaching project for endoscopic third ventriculostomy (ETV) procedures and a subsequent program to develop neurosurgery as a permanent specialty in Kenya and Zanzibar were created and sponsored by the Neurosurgery Education and Development (NED) Foundation and the Foundation for International Education in Neurological Surgery. The objective of this work was to evaluate the results of surgical training and medical care in both projects from 2006 to 2013. METHODS Two portable neuroendoscopy systems were purchased and a total of 38 ETV workshops were organized in 21 hospitals in 7 different countries. Additionally, 49 medical expeditions were dispatched to the Coast General Hospital in Mombasa, Kenya, and to the Mnazi Moja Hospital in Zanzibar. RESULTS From the first project, a total of 376 infants with hydrocephalus received surgery. Six-month follow-up was achieved in 22%. In those who received follow-up, ETV efficacy was 51%. The best success rates were achieved with patients 1 year of age or older with aqueductal stenosis (73%). The main causes of hydrocephalus were infection (56%) and spina bifida (23%). The mobile education program interacted with 72 local surgeons and 122 nurses who were trained in ETV procedures. The second project involved 49 volunteer neurosurgeons who performed a total of 360 nonhydrocephalus neurosurgical operations since 2009. Furthermore, an agreement with the local government was signed to create the Mnazi Mmoja NED Institute in Zanzibar. CONCLUSIONS Mobile endoscopic treatment of hydrocephalus in East Africa results in reasonable success rates and has also led to major developments in medicine, particularly in the development of neurosurgery specialty care sites.

[Recommendations on the use of 5-amino-levulinic acid in surgery of malignant gliomas. Consensus document. The Neuro-oncology Working Group of the Spanish Neurosurgical Society (SENEC)]

Among the prognostic factors when it comes to patients with high-grade gliomas, we find the radicality of the surgery performed. The limitations of this factor are caused by either the extension of the tumour or its location in an eloquent area. To achieve this goal, in the last few years we have developed several methods that allow us to maximise tumour resection, while always trying to cause the least possible co-morbidity. One of these methods includes the use of 5-amino-levulinic acid (5-ALA) and the development of fluorescence guided surgery. However, optimal performance requires knowledge of the product employed, the mode of administration and precautions to consider. Members of the neuro-oncology work group of the Spanish Neurosurgical Society (SENEC) have prepared this guideline or consensus document for anyone who wishes to become familiar with the use of 5-ALA fluorescence-guided surgery in the management of high-grade gliomas. For those who already utilise this technique, this document can be useful for consultation purposes.

[Mini-open approaches in anterior lumbar spine surgery]

INTRODUCTION

The anterior spine approach known as «mini-open» was introduced a few years ago for the surgical treatment of spine diseases. This approach allows the anterior, body and intervertebral disc structures to be exposed, as well as the anterior compression of the dural sac and the reconstruction and/or stabilisation of the levels of interest with an appropriate system. In the present article we present our experience in mini-open anterior spine surgery (MOASS) approach in the treatment of lumbar spine diseases.

MATERIAL AND METHODS

We performed 74 anterior spine approaches using open surgery between the period January 2004 and July 2011. In 38 cases we used the MOASS technique at different levels: thoracic, lumbar, and infraumbilical extraperitoneal.

RESULTS

There were no surgical or post-operative deaths, or further neurological deficits arising from the surgical procedure in any of the techniques (classic versus MOASS). The few complications were corrected with the appropriate treatment.

CONCLUSIONS

Using the MOASS technique we have performed corrective surgery on spine injuries that could affect the thoracic spinal column, with similar results to those obtained using the classic approach and with obvious advantages.

Loss of heterozygosity at 1p-19q induces a global change in oligodendroglial tumor gene expression

Oligodendroglial tumors presenting loss of heterozygosity (LOH) at 1p and 19q have been shown to be sensitive to chemotherapy, thus making 1p-19q status testing a key aspect in oligodendroglioma diagnosis and prognosis. Twenty-nine tumor samples (19 oligodendrogliomas, 10 oligoastrocytomas) were analyzed in order to obtain a molecular profile identifying those bearing 1p-19q LOH. Other genomic anomalies usually present in gliomas, such as EGFR amplification, CDKN2A/ARF deletion, 10q LOH and TP53 mutation, were also studied. Tumors with 1p-19q LOH overexpressed genes related to neurogenesis. Genes linked to immune response, proliferation and inflammation were overexpressed in the group with intact 1p-19q; this group could in turn be further divided in two subgroups: one overexpressing genes involved in immune response and inflammation that did not show major genetic aberrations other than the TP53 mutation and EGFR trisomy in a few cases, and another overexpressing genes related to immune response and proliferation that had a predominance of samples carrying several anomalies and presenting worse outcomes. This molecular signature was validated by analyzing a set of ten tumor samples (three oligodendrogliomas, seven oligoastrocytomas); all ten samples were correctly assigned. LOH at 1p-19q results in haploinsufficiency and copy number reduction of several genes, including NOTCH 2; this phenomenon produces a global change in gene expression inducing a pro-neural status that results in restrictions to cell migration and proliferation. Tumors without LOH at 1p-19q exhibit the opposite characteristics, explaining their more aggressive behavior.

Determination of metabolite concentrations in human brain tumour biopsy samples using HR-MAS and ERETIC measurements

Accurate determination of the concentration of the metabolites contained in intact human biopsies of 10 glioblastoma multiforme samples was achieved using one-dimensional (1)H high-resolution magic angle spinning (HR-MAS) NMR combined with ERETIC (electronic reference to in vivo concentrations) measurements. The amount of sample used ranged from 6.8 to 12.9 mg. Metabolite concentrations were measured in each sample using two methods: with DSS (2,2-dimethyl-2-silapentane-5-sulfonate sodium salt) as an internal reference and with ERETIC as an external electronically generated reference. The ERETIC signal was shown to be highly reproducible and did not affect the spectral quality. The concentrations calculated by the ERETIC method in model solutions were shown to be independent of the salt concentration in the range typically found in biological samples (0-250 mM). The ERETIC method proved to be straightforward to use in tissues and much more robust than the internal standard method. The concentrations calculated using the internal DSS concentration were systematically found to be higher than those determined using the ERETIC technique. These results indicate a possible interaction of the DSS molecules with the biopsy sample. Moreover, variations in the sample preparation process, with possible loss of DSS solution, may hamper the quantification process, as happens in one of the ten samples analysed. In this study, the ERETIC method was validated on model solutions and used in brain tumour tissues. Calculated metabolite concentrations obtained with the ERETIC procedure matched the values determined in the same type of tumours by in vivo, ex vivo and in vitro methodologies.

[Assessment of reliable quantification of the dynamics of cerebrospinal fluid by magnetic resonance imaging in idiopathic normal pressure hydrocephalus]

INTRODUCTION

A combination of good clinical selection with reliable quantification of diverse parameters that characterize the dynamics of cerebrospinal fluid (CSF) flow from phase-contrast magnetic resonance imaging may identify patients with idiopathic normal pressure hydrocephalus (NPH).

MATERIAL AND METHODS

We have carried out a quantitative analysis of 38 subjects (19 healthy subjects and 19 patients with suspected idiopathic NPH). The images were acquired using a 1.5 T MR unit with a phase-contrast sequence in an oblique-transversal plane perpendicular to the Sylvius aqueduct codified to 20 cm/s and with 27 observations per cardiac cycle by means of retrospective synchronization. The area was defined to half the height of the peak velocity, to maximize accuracy. Parameters quantified were mean flow, maximum systolic and diastolic flow, maximum systolic and diastolic velocity, mean velocity, CSF production and stroke volume.

RESULTS

All the parameters measured showed a significant difference (ANOVA: p<or=0,05) between controls and patient except for the maximum systolic velocity (p=0.17). It was observed in the discriminant analysis that the two groups (controls and patients) were classified correctly in 92.1% with the use of the maximum systolic flow and CSF production.

CONCLUSIONS

Semiautomatic quantification of the dynamics of CSF by means of MRI differentiates patients with hyperdynamic state from the control subjects, with significant differences that can be used to classify idiopathic HNP.

MRS as endogenous molecular imaging for brain and prostate tumors: FP6 project "eTUMOR"

Molecular imaging has become during the last years in an important tool for supporting cancer diagnosis and prognosis. PET and SPECT are the most common molecular imaging techniques, although very promising and specific biological molecular agent contrast for CT and MRI are being recently developed. However, the above imaging techniques require exogenous contrast agents and usually a sole molecular image can be obtained at once. On the contrary, in vivo magnetic resonance spectroscopy (MRS), in particular 1H MRS can simultaneously provide several molecular images using endogenous metabolites. In addition to biochemical spatial information from molecular imaging spectroscopy, MRS can also provide average metabolite profile of the selected affected tissue region. Initially MRS, especially 1H MRS, was extensively applied to complete and improve the diagnosis and prognosis of central nervous system (CNS) pathologies, in particular brain tumors. However, during the last years the MRS applications have been extent to the diagnosis of different very common cancer types such as breast, prostate, colon carcinoma, and ovarian, among others. Likewise, MRS has been also used for lymph node assessment. In this contribution, the added value of MRS for the diagnosis, prognosis, and treatment selection of two different, important types of cancer: (1) brain tumors and (2) prostate, will be presented and discussed. Brain tumors are the leading cause of death in children under 15, and although in adults, brain cancers are proportionately less common than other cancers, it is a devastating disease with high mortality. There is a great need to increase our understanding of brain tumor biology to improve diagnosis and to develop new treatments. 1H MRS is currently the only noninvasive method that can be used to investigate molecular profile of brain tumors and also provide molecular images, more than six in one acquisition, of the distribution of chemicals in a tumor, which are also generally heterogeneous. A summary of the applications of 1H MRS to the in vivo diagnosis and prognosis of brain tumors will be presented. In addition, examples of metabolite limits, infiltration and high cellularity location for neurosurgery applications by MRS molecular images will be shown. Likewise, new ex vivo methods of studying the detailed biochemistry of tumor biopsies as metabolomic (high resolution magic angle spinning [HR-MAS]) and transcriptomic (DNA microarrays) will be discussed as complementary to in vivo MRS (FP6 European project eTUMOR). A preliminary comparison between molecular images from PET and 1H MRS will be also presented. Finally, the application of 1H MRS to the improvement of prostate diagnosis and prognosis, the second leading cause of cancer death, will also discussed, with particular attention to the location cancer contribution from MRS molecular images.

Systemic movement of Agrobacterium tumefaciens in several plant species

AIMS

The systemic movement of Agrobacterium spp. inside plants of different species was studied to determine the most valuable diagnostic methodology for their detection.

METHODS AND RESULTS

Pathogenic agrobacteria were detected by isolation and PCR in tissue away from primary tumours in tomato plants grown in the presence of Agrobacterium spp. Moreover, this bacterium was also able to induce secondary tumours beyond the inoculation site. In addition, the capacity of agrobacteria to translocate and induce secondary tumours was analysed in rose, grapevine, chrysanthemum, cherry and peach x almond hybrid GF677. No differences among strains of Agrobacterium spp. were detected in secondary tumour development, although some of them induced a significantly higher number of primary tumours in some species. Movement of inoculated pathogenic cells of four strains was also demonstrated in symptomless portions of the plant stems by isolation and PCR. Finally, pathogenic agrobacteria were detected in root, crown and stem portions of naturally infected walnuts. In all assays, PCR was the most efficient technique for detecting the movement of Agrobacterium spp. within the plants.

CONCLUSIONS

Migration of agrobacteria inside plants is a complex phenomenon and more extensive than previously reported. Therefore, efficient and sensitive detection methods such as PCR must be used to select clean plants to avoid latent infections of Agrobacterium spp.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results show that migration of Agrobacterium spp. could be relatively frequent in several cultivated fruit trees, and systemic infections should be taken into account when designing strategies for controlling crown gall disease.

Factors Affecting Pseudomonas savastanoi pv. savastanoi Plant Inoculations and Their Use for Evaluation of Olive Cultivar Susceptibility

ABSTRACT Pseudomonas savastanoi pv. savastanoi causes olive knot disease, which is present in most countries where olive trees are grown. Although the use of cultivars with low susceptibility may be one of the most appropriate methods of disease control, little information is available from inoculation assays, and cultivar susceptibility assessments have been limited to few cultivars. We have evaluated the effects of pathogen virulence, plant age, the dose/response relationship, and the induction of secondary tumors in olive inoculation assays. Most P. savastanoi pv. savastanoi strains evaluated were highly virulent to olive plants, but interactions between cultivars and strains were found. The severity of the disease in a given cultivar was strongly dependent of the pathogen dose applied at the wound sites. Secondary tumors developed in noninoculated wounds following inoculation at another position on the stem, suggesting the migration of the pathogen within olive plants. Proportion and weight of primary knots and the presence of secondary knots were evaluated in 29 olive cultivars inoculated with two pathogen strains at two inoculum doses, allowing us to rate most of the cultivars as having either high, medium, or low susceptibility to olive knot disease. None of the cultivars were immune to the disease.

Association of chromosome 7, chromosome 10 and EGFR gene amplification in glioblastoma multiforme

Glioblastoma multiforme (GBM) is characterized by intratumoral heterogeneity in both histomorphological and genetic changes, displaying a wide variety of numerical chromosome aberrations, the most common of which are trisomy 7 and monosomy 10. The amplification of the epidermal growth factor receptor (EGFR) gene is the most frequently reported genetic abnormality. The associations between these parameters and their implication in the tumoral progression are poorly understood. We performed simultaneous fluorescence in situ hybridization (FISH) with centromeric DNA probes for chromosomes 7 and 10 in smear preparations, and EGFR gene amplification by PCR from 25 cases of GBM. Trisomy/ polysomy for chromosome 7 was present in 76% of cases and monosomy 10 in 68%. Both alterations were associated in 56% of cases. The EGFR gene was amplified in 52% of tumors; in 44% associated with trisomy/ polysomy 7, and in 36% with monosomy 10. The three parameters were associated together in 28% of cases. Kaplan-Meier survival rate analysis demonstrated lower survival rates in patients with monosomy 10, trisomy 7, and monosomy associated with trisomy 7. The other combinations were not different in frequency in relation to survival. In the present study, trisomy/polysomy 7 and monosomy 10 have been found to be frequently associated. The combination of both anomalies is probably important in the tumorigenesis of glioblastoma. Moreover, this association is apparently independent of EGFR gene amplification, which could be a later event in this process.

1H and 13C HR-MAS spectroscopy of intact biopsy samples ex vivo and in vivo 1H MRS study of human high grade gliomas

High-resolution magic angle spinning (HR-MAS) one- and two-dimensional 1H and 13C nuclear magnetic resonance (NMR) spectroscopy has been used to study intact glioblastoma (GBM) brain tumour tissue. The results were compared with in vitro chemical extract and in vivo spectra. The resolution of 1H one-dimensional, 1H TOCSY and 13C HSQC HR-MAS spectra is comparable to that obtained on perchloric extracts. 13C HSQC HR-MAS spectra have been particularly useful for the identification of 37 different metabolites in intact biopsy tumours, excluding water and DSS components. To our knowledge, this is the most detailed assignment of biochemical compounds obtained in intact human tissue, in particular in brain tumour tissue. Tissue degradation during the recording of the NMR experiment was avoided by keeping the sample at a temperature of 4 degrees C. Detailed metabolical compositions of 10 GBM (six primary, two secondary and two unclassified) were obtained. A good correlation between ex vivo and in vivo MRS has been found.

Behavior of a Virulent Strain Derived from Agrobacterium radiobacter Strain K84 After Spontaneous Ti Plasmid Acquisition

ABSTRACT The behavior of the virulent transconjugant K84N6 derived from Agrobacterium radiobacter strain K84 after spontaneous Ti plasmid transfer in crown gall tissue in a biocontrol experiment was studied and compared with the behavior of the wild-type A. tumefaciens donor of the Ti plasmid. The main difference between the strains was a greatly reduced ability of the transconjugant to catabolize nopaline. Host range, ability to induce tumors in several fruit trees, and stability of the pathogenic determinants in isolates from tumors did not differ between the strains. Nevertheless, in a biocontrol experiment, the transconjugant was not controlled by strain K84 or K1026 in peach x almond hybrids and survived in the plant rhizo-sphere for 9 months with larger population densities than the wild strain. The appearance and persistence in soil of strains harboring a Ti plasmid in the K84 chromosomal background could represent a risk in the medium term, if they show good competitive ability.

[Petrous bone approach for the surgery of petroclival meningiomas]

Four patients, 3 woman and 1 man, with giant petroclival meningiomata are presented. In all cases the tumor size exceed 44 mm in its greater diametre. Main clinical symptoms were endocranial hypertension and cranial nerves deficit. A modified transcochlear approach in two stages was used. A total petrosectomy was performed, using the petrosygmoidal via for opening the dura. Transversus and sygmoid sinus were spared. Total removal was achieved in 2 cases, subtotal and partly in each of the other 2. No operative mortality occurred (hospital exitus) and neurologic morbility related to V-VI-VII and VIII cranial nerves and 1 hemyparesia was recorded. The AA. explain and comment the fundamentals of the followed procedure and compare, as well, the own outcomes with those reported by more classic alternatives. Finally, the conclusion is drawn out that retroclival meningiomata are conditions treatable, although always are difficulty approached and demand meticulous microsurgical techniques.

Delayed extradural hematoma after mild head injury: report of three cases

BACKGROUND

Extradural hematoma has been classically considered to be an acute complication of head injury whose maximum development takes place in the minutes following trauma. Delayed extradural hematoma (DEH) is defined on the basis of an exclusively radiologic criterion: epidural hematoma that is not present in the first neuroradiologic examination made after trauma but that appears in sequential neuroradiologic examinations during patient evolution. This is an infrequent complication that usually appears in hypotensive multiple trauma patients or is related to severe head injury with other intracranial lesions.

CASE DESCRIPTION

We present three cases of DEH after mild head injury (GCS > 12) without associated intracranial or traumatic systemic lesions. Therefore, those usually considered to be "protective mechanisms" responsible for delayed development of an extradural hematoma were absent in our three patients. Diagnosis was attained by means of repetition of cranial computed tomography (CT) scan after neurologic impairment was noted. Surgical evacuation of DEH was immediately performed after diagnosis. Postoperative outcome was favorable in two patients who suffered DEH in the supratentorial compartment. One patient who presented a posterior fossa DEH died 3 days after surgery.

CONCLUSIONS

Early diagnosis and immediate treatment have proved to be essential for improving the prognosis of patients affected by DEH. Hospital admission under neurologic observation is recommended for patients who have sustained mild head injury associated with those factors that are related to the development of DEH, including GCS score under 15 or the detection of a skull fracture. Normality of a CT scan does not rule out subsequent appearance of delayed traumatic lesions.

Preoperative embolization of solid cervicomedullary junction hemangioblastomas: report of two cases

Solid cervicomedullary haemangioblastomas represent a small but technically challenging subset of posterior fossa haemangioblastomas because of their site, high vascularity and tendency to bleed. We present our experience with preoperative embolisation of two solid cervicomedullary haemangioblastomas. In both cases the main feeding artery was the posterior inferior cerebellar artery. Arterial pedicles were catheterised with a microcatheter. The embolic material was small particles (150-250 microm) of polyvinyl alcohol. The result was almost complete preoperative obliteration of the vessels of the tumours. The procedure was well tolerated and facilitated easier bloodless, successful resection in both cases, 24 h after embolisation.

Surgical treatment of epidermoid cysts of the cerebellopontine angle

A total of 40 patients with epidermoid cysts of the cerebellopontine angle (CPA) underwent surgery between 1980 and 1993. Total resection was achieved in 30 cases (75%); in 10 cases (25%) parts of the cyst capsule were left because they adhered to the brainstem and vascular structures of the CPA. One patient with very large bilateral epidermoid cysts, who underwent complete bilateral resection in one stage, died of pulmonary aspiration and infection. As of their latest clinical and radiological follow-up examinations (mean 5.7 years), 93% of the patients are able to lead useful lives. Three cases of cyst regrowth have been observed thus far. Modern radiological tools and microsurgery techniques have considerably improved the completeness of cyst resection and reduced postoperative mortality and morbidity rates; however, there still are some cases in which complete resection is impossible without producing severe neurological deficits.

Dietary effects on stunting syndrome in poults

Experiments were done to determine the effect of feeding diets of different ingredient composition to poults experimentally infected with stunting syndrome (SS) at 1 day of age. In Experiment 1, feeding a complex diet (CPX) containing fish meal and sunflower meal as the main protein sources eliminated the adverse effects of SS inoculation on performance traits as compared with SS effects on poults fed a corn and soybean meal (CS) diet. In Experiments 2 and 3, the effects of SS were more severe than in Experiment 1. In these experiments, the CPX diet only partly overcame the adverse effects of SS on performance (i.e., in Experiment 2, growth depressions from 2 to 5 days of age were 90.3 and 59.6% in SS-inoculated poults fed the CS and CPX diets, respectively, as compared with uninoculated, control poults fed the same diets). Properties of the CPX diet that made it effective in reducing the severity of SS were not evident from the results of Experiment 3. Replacing soybean meal with soy protein or canola meal was ineffective as compared with the use of a mixture of sunflower meal, fish meal, meat and bone meal, and corn gluten meal.

Responses of turkey poults to virginiamycin as influenced by litter condition and experimentally induced stunting syndrome

Two experiments were conducted to evaluate the effect of virginiamycin (VM, 22 mg/kg of diet) on performance of uninfected (CON) turkey poults and those infected (INO) with stunting syndrome and reared on used woodshavings (Experiment 1) or on clean or used woodshavings (Experiment 2). Virginiamycin improved BW (P less than .001) and feed efficiency (FE) (P less than .05) from 1 to 29 days of age, irrespective of type of litter or disease condition. The increase in BW induced by VM, however, was greatest when poults were kept on used litter, resulting in significant (P less than .05) VM by litter interaction. Induced stunting syndrome depressed BW (P less than .01) to 29 days of age and impaired FE from 1 to 9 days of age (P less than .05) and from 5 to 9 days of age (P less than .01) in Experiments 1 and 2, respectively. Virginiamycin did not prevent early adverse effects of INO on BW and FE, but facilitated notable recovery of INO poults relative to INO poults not fed VM. Virginiamycin increased specific activities of maltase and sucrase of the jejunum of CON poults in Experiments 1 and 2; in Experiment 2, this VM effect was evident irrespective of type of litter. Maltase-specific activity and sucrase were reduced by INO (P less than or equal to .05 and P less than or equal to .01 in Experiments 1 and 2, respectively) and VM did not modify this effect. The maltase and sucrase data suggest that VM improved BW and FE of CON poults, in part, by helping to maintain digestive and absorptive functions of the small intestine during the early growth period, but, in the instance of INO poults, VM was not effective in this regard.

[Meningiomas: immunohistochemical analysis of 26 cases]

We have analyzed, with immunohistochemical staining techniques 26 meningiomas of CNS. Vimentin intermediate filaments was present in all cases in the cytoplasm of tumoral cells. Single epithelium cytokeratin was positive in only 19% cases, same that was obtained with S-100 protein. Whereas 69% of cases expressed epithelial membrane antigen. No case was stained positively with Actin, Desmin and GFAP. The results obtained for others authors are analyzed.

Correlations of female steroid hormone receptors with histologic features in meningiomas

A series of 39 samples were obtained from meningiomas in 28 patients in order to investigate the relationships of the oestrogen receptor (OER) and progesterone receptor (PR) with the tumoural subtype and some histological features. Twenty-one samples were positive (greater than 10 fmole/mg protein), 7 were OER-PR-negative, and 1 was positive in both receptors. Twenty-two samples were considered as syncitial, 7 transitional, 7 fibroblastic and 3 angioblastic. The histological subtype was not found to be significantly related to the presence or absence of PR. Relations were not observed between the progestin receptor and the following histological parameters: cellular pattern, cell density, nuclear polymorphism, mitosis, lymphoplasmacellular infiltrates, degree of vascularization, psammoma bodies and interstitial fibrosis. Only the presence of intratumoural necrosis was significantly related with a low PR levels. However, progesterone binding activity was lower in tumours with numerous psammomas, fibroblastic cell pattern and interstitial fibrosis. The clinical and biological significance of these results is discussed.

[Tumors of the choroid plexus: morphologic and immunohistochemical study]

We present a morphological and immunohistochemical study on three papillomas and one carcinoma of the choroid plexus. Clinical characteristics are analysed. Morphological criteria for malignancy are: solid histological pattern, cellular polymorphism, nuclear atypia and infiltration of nervous tissue. The immunohistochemical study shows the value of GFAP, S-100 protein, HNK-1 and Vimentin as specific markers. In the discussion we point out the differential diagnosis between these types of tumors and the metastasis from papillary carcinomas and ependymomas.

[Differential immunohistochemical characteristics of meningiomas and other neoplasms of the central nervous system]

We present an immunohistochemical study of 16 meningiomas and 19 CNS tumors including gliomas, neurinomas and metastatic carcinomas, in order to establish a histopathologic differential diagnosis, using formalin-fixed and paraffin-embedded material. The antibodies analysed included vimentin, GFA-protein, cytokeratin, S-100 protein and epithelial membrane antigen. Meningiomas always express vimentin as marker, and occasionally cytokeratin and EMA. The most constant antigens demonstrated in astrocytomas were GFA-protein and vimentin, and occasionally we were able to detect S-100 protein. Neurinomas proved positive to S-100 protein, and metastases presented cytokeratin and EMA reactivity. Our results confirm the existence of diverse immunohistochemical patterns within CNS tumors, a fact that can be useful in routine differential diagnosis.

Meningiomas: karyotypes and histological patterns

The cytogenetic findings, based on G-banding, in six meningiomas are reported. Normal karyotypes were found in three cases and monosomy of chromosome 22 in the remaining three. In one of these three cases, a malignant meningioma, several chromosomes were lost, gonosome Y included. The possible significance of the association of chromosome alterations in meningiomas with the histology of the tumor and its biological aggressivity is discussed.

Long-term results of percutaneous gasserian ganglion lesions

Percutaneous radiofrequency lesion of the Gasserian ganglion was performed between 1974 and 1984 in ninety-eight patients for the relief of trigeminal neuralgia. The average follow-up period was 4.5 years. Age, sex, and duration of illness were unrelated to outcome. Satisfactory analgesia was achieved in 68 patients. Thirty-one percent had return of pain (30 cases). Recurrent neuralgia occurred most frequently during first postoperative year (46%). Patients with marked sensory deficits had a reduced risk of recurrence. Postoperative complications included: reduced or absent corneal reflex (18 cases), corneal keratitis (3 cases) and anesthesia dolorosa (2 cases).