Influence of grain processing on acid-base balance in feedlot steers.

Grain processing (e.g. grinding, steaming, pelleting, flaking) has been reported to modify the incidence of ruminal disturbances in feedlot cattle. This study investigated the effects of two grain processing methods widely used in Spanish feedlots (grinding and pelleting) on animal performance, blood acid-base balance, blood electrolyte levels and serum lactate in a 140-day feedlot experiment with double-muscled Belgian Blue steers. The main aim of the study was to evaluate the way in which these two feeds modify blood acid-base balance, which is closely associated with ruminal pH. In light of our results we conclude that the animals that received the pelleted feed showed a more stable acid-base balance over time than those fed a ground feed. Nevertheless, higher levels of L-lactate and lower base excess (BE) and HCO(3)(-) values for cattle fed pelleted grain reflect a greater risk of grain-acid overload.

Documento de consenso sobre la utilización de profilaxis antibiótica en cirugía y procedimientos dentales / Consensus document on the use of antibiotic prophylaxis in dental surgery and procedures

La profilaxis antibiótica en Odontología tiene como objetivo prevenir la aparición de infección a partir de la puerta de entrada que produce la actuación terapéutica, por lo que se encuentra indicada siempreque exista un riesgo importante de infección, ya sea por las características mismas de la operación o por las condiciones locales o generales del paciente. Sin embargo, los ensayos clínicos con antibióticos en patologías dentarias responden poco a los criterios metodológicos requeridos, y además no son lo suficientemente numerosos. Se presentan los resultados de una conferencia de expertos integrada porlos Presidentes de Sociedades Científicas Españolas más representativas que han analizado la bibliografía existente y han aportado sus valiosas experienciasprofesionales. Se describen las circunstancias técnicas, se analizan los fundamentos biológicos y farmacológicos y se aplican a las situaciones médicas más repre-sentativas. Se concluye que la profilaxis antibiótica en Odontología cuenta con indicaciones bien fundamentadas y precisas, ofreciendo a la comunidad científica internacional un protocolo práctico de actuación

The goal of antibiotic prophylaxis in Odontology is to prevent the onset of infections through the entranceway provided by the therapeutic action, therefore it is indicated providing there is a considerable risk of infection, either because of the characteristicsof the operation itself or the patient’s local or general condition. Nonetheless, clinical trials with antibiotics in dental pathologies have had scant regard for the required methodological criteria and,in addition, are not sufficiently numerous. This text presents the results of an expert conference comprising the Presidents of the most representative Scientific Societies in Spain who have analyzed the existing literature and have drawn on their valuable professionalexperience. It describes the technical circumstances, analyzes the biological and pharmacological foundations and their application to the most representative medical situations. It is concluded that antibiotic prophylaxis in Odontology has certain well-founded, preciseindications and offers the international scientific community a practical protocol for action

Documento de consenso sobre la utilización de profilaxis antibiótica en cirugía y procedimientos dentales / Consensus document on the use of antibiotic prophylaxis in dental surgery and procedures

La profilaxis antibiótica en Odontología tiene como objetivo prevenir la aparición de infección a partir de la puerta de entrada que produce la actuación terapéutica, por lo que se encuentra indicada siempre que exista un riesgo importante de infección, ya sea por las características mismas de la operación o por las condiciones locales o generales del paciente. Sin embargo, los ensayos clínicos con antibióticos en patologías dentarias responden poco a los criterios metodológicos requeridos, y además no son lo suficientemente numerosos. Se presentan los resultados de una conferencia de expertos integrada por los Presidentes de Sociedades científicas españolas más representativas que han analizado la bibliografía existente y han aportado sus valiosas experiencias profesionales. Se describen las circunstancias técnicas, se analizan los fundamentos biológicos y farmacológicos y se aplican a las situaciones médicas más representativas. Se concluye que la profilaxis antibiótica en Odontología cuenta con indicaciones bien fundamentadas y precisas, ofreciendo a la comunidad científica internacional un protocolo práctico de actuación (AU)

The goal of antibiotic prophylaxis in Odontology is to prevent the onset of infections through the entrance way provided by the therapeutic action; therefore it is indicated provided there is a considerable risk infection, either because of the characteristics of the operation itself or the patient´s local or general condition. Nonetheless, clinical trials with antibiotics in dental pathologies scarcely adhere to the required methodological criteria and in addition, are not sufficiently numerous. This text presents the results of an expert conference comprising the Presidents of the most representative Scientific Societies in Spain who have analyzed the existing literature and have drawn on their valuable professional experience. It describes the technical circumstances, analyzes the biological and pharmacological foundations and their application to the most representative medical situations. It is concluded that antibiotic prophylaxis in Odontology has certain well-founded, precise indications and offers the international scientific community a practical protocol for action (AU)

Meningeal Rosai-Dorfman disease: report of three cases and literature review.

Rosai-Dorfman disease is a well-recognized clinicopathological entity, which in rare cases affects the central nervous system, where it mimics meningioma. We describe three cases and review the literature. Histological and immunohistochemical confirmation is essential for definitive diagnosis. In addition to emperipolesis (lymphophagocytosis), reactivity for S-100 and CD68 and nonreactivity for CD-la immunostaining are characteristic features of this histioproliferative disease. In contrast to meningioma, this tumor usually occurs in young males and infiltrates the brain parenchyma.

Patterns of central nervous system recurrence in patients with systemic human immunodeficiency virus-associated non-hodgkin lymphoma.

BACKGROUND: Central nervous system involvement is a common manifestation of non-Hodgkin lymphoma (NHL) in human immunodeficiency virus (HIV)-infected individuals. The purpose of this study was to review the frequency and pattern of neurologic manifestation of lymphoma in a cohort of HIV-infected individuals with systemic NHL. METHODS: Sixty-two patients with HIV-associated systemic NHL received infusional cyclophosphamide, doxorubicin, and etoposide. Five patients with lymphomatous meningitis at presentation received whole brain radiation therapy plus intrathecal chemotherapy (ITC). Of the remaining 57 patients, prophylactic ITC was recommended only for those patients with lymphomatous bone marrow involvement and/or high grade histology (N = 31). RESULTS: Thirteen patients (21%) had histologically documented (N = 6) or presumed (N = 7) central nervous system involvement, including 7 patients (11%) with meningeal lymphoma discovered either at presentation (N = 5) or soon after diagnosis (N = 2), and 6 patients (10%) with cerebral mass lesions at the time of disease recurrence consistent with parenchymal brain involvement. Five of six parenchymal brain recurrences occurred in the setting of progressive systemic disease. Four of 7 patients (57%) with meningeal lymphoma detected at presentation (N = 5) or within 3 months of presentation (N = 2) responded to therapy and survived >1 year. Of the 26 patients assigned to receive no prophylactic ITC, no patient developed an isolated meningeal recurrence and 1 patient developed an isolated parenchymal brain recurrence. CONCLUSIONS: The findings of the current study suggest that in patients with HIV-associated systemic lymphoma, meningeal lymphoma is potentially curable, parenchymal brain recurrence usually occurs in the setting of uncontrolled systemic disease, and prophylactic ITC may not be necessary for patients with intermediate grade histology and uninvolved bone marrow.

Solitary primary CNS lymphoma: long term survival following total resection.

Primary non-Hodgkin's CNS lymphoma is rare, constituting 0.3-1.5% of all intracranial neoplasms in patients without AIDS. In the past 10 years the incidence has tripled in this population. The role of surgery is commonly limited to obtaining adequate tissue for diagnosis. This has precluded the evaluation of total surgical resection for a surgically accessible solitary lesion. We have encountered a 36-year-old healthy white male with primary CNS lymphoma who is HIV-negative and who has survived over five years disease free after total surgical resection of his lymphoma.

Pretreatment with intraventricular aurintricarboxylic acid decreases infarct size by inhibiting apoptosis following transient global ischemia in gerbils.

The goal of this study was to determine whether aurintricarboxylic acid (ATA), an endonuclease inhibitor known to inhibit apoptosis, could ameliorate cell damage in a gerbil model of transient ischemia. Transient ischemia was induced in gerbils by bilateral carotid artery occlusion for a period of 5 minutes. Four micrograms of ATA was administered intraventricularly 1 hour before ischemia, and the brains were assessed histologically 1 week later to quantitate cell loss in the vulnerable CA-1 subsector of the hippocampus. In a separate set of experiments, 4 microg of ATA was administered intraventricularly 1 hour before ischemia and the brains were assessed for evidence of DNA fragmentation by the TUNEL method. There was only a 16% cell loss compared with nonischemic controls in animals pretreated with ATA that was significantly less (p < 0.05) than the 48% cell loss in animals pretreated with saline alone. TUNEL-positive cells were first evident at 3 days and were still present at 7 days subsequent to ischemia. Maximal staining occurred at 4 days. Pretreatment with ATA virtually eliminated TUNEL staining at 4 days. These results support the hypothesis that the delayed cell death secondary to transient ischemia is, in part, apoptotic. Furthermore, ATA afforded significant neuronal protection and prevented DNA fragmentation.

Rhabdoid transformation of tumor cells in meningiomas: a histologic indication of increased proliferative activity: report of four cases.

Four cases of meningeal tumors in adults (ages ranging from 28 to 84 years) are presented. All had the typical gross appearance of meningiomas at operation. In three tumors, areas of meningothelial or fibroblastic meningiomas showed transition to cell groups of the rhabdoid type. In the fourth case only rhabdoid cells were encountered, possibly representing a total "take-over" of a meningioma by rhabdoid elements. In the three cases with mixed pattern, the rhabdoid cells showed more anaplasia and atypism than the conventional meningiomatous elements. In case 3 this was expressed by very high MIB-1 positivity in the rhabdoid cells and absence of same in the fibroblastic meningiomatous elements. These cases (the first three with certainty, the fourth with a strong likelihood) indicate that the phenotypic changes to cells with "rhabdoid" morphology may involve meningiomas and that such change is associated with aggressive biologic and clinical behavior of the tumors showing this type of alteration.

Paraganglioma of the filum terminale: case report and literature review.

A rare case of a paraganglioma of the filum terminale is reported. The patient presented with headache and papilledema. Magnetic resonance imaging demonstrated enlarged ventricles of the brain and a well-demarcated intradural spine tumor. After resection of the tumor, the papilledema and headaches resolved, and the ventricles returned to normal size. Pathologic examination revealed a paraganglioma of the filum terminale. We present this rare case and review the literature of spinal paragangliomas as well as the association of spinal tumors with hydrocephalus.

Glioma of the tongue.

A case of glioma of the tongue that was treated successfully by simple excision and repair is presented. It may represent neural tissue that remains in the occipital somites that differentiate into the tongue muscles. Histologically, it consists of sheets of glial tissue. The literature is reviewed, and the case is discussed.

Comparative cytokine gene expression in synovial tissue of early rheumatoid arthritis and seronegative spondyloarthropathies.

Interleukin 1-beta (IL-1 beta), IL-2, IL-4, IL-5, IL-6, IL-8, tumour necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression was determined in knee synovium of 16 patients with rheumatoid arthritis (RA) and 16 patients with seronegative spondyloarthropathies (SSP), by using polymerase chain reaction (PCR) amplification. The pattern of cytokines observed in RA synovium is of the macrophage-fibroblast type, with the highest expression of IL-1 beta and TGF-beta. GM-CSF and IL-2 bands were visualized in a minority of patients. Neither IL-4 nor IL-5 could be detected. No significant differences were observed in the cytokine profile between patients with early (< 12 months) and more advanced disease. No differences were observed according to gender, age, rheumatoid factor status and the duration of knee synovitis. The pattern of cytokines in the synovium of SSP patients is similar to that observed in RA patients and does not change in relation to disease duration. IL-2 was the only T-cell cytokine observed. These data provide evidence that the macrophage-fibroblast cells have an important role in early and more advanced rheumatoid synovitis, and show that this is also true for SSP peripheral synovitis.

Epithelial differentiation in intraspinal meningiomas.

To investigate the epithelial features of intraspinal meningiomas, 25 intraspinal meningiomas and 25 intracranial meningiomas were examined for the presence of pseudopsammoma bodies with hematoxylin-eosin and periodic acid-Schiff staining. In addition, we investigated the expression of keratin and epithelial membrane antigen (EMA) by immunohistochemical methods. Pseudopsammoma bodies were found in 3 of 25 cases of intracranial meningiomas (12%), but no definitive pseudopsammoma bodies were observed the intraspinal meningiomas. Three cases (12%) of intraspinal meningiomas and 9 cases (36%) of intracranial meningiomas, including 3 cases with pseudopsammoma bodies, were immunoreactive for keratin. All 25 (100%) intracranial meningiomas and 20 of 25 (84%) intraspinal meningiomas were reactive for EMA. In the intraspinal meningiomas, 4 of 25 cases (16%) showed no reactivity for EMA. These findings suggest that the origin of certain cell components of meningiomas may be different according to the site of the tumor or that the nature of meningioma may be modified by the local environment.

A histopathological study of craniopharyngioma with special reference to its stroma and surrounding tissue.

The numerous pathology reports on craniopharyngioma describe the classical features of squamous epithelium and keratin. Relatively little attention has been paid to its stroma and the surrounding tissue. We focused our observation on these two areas in a retrospective study of craniopharyngiomas in 36 operative cases and 5 autopsy cases. The tumor interdigitated with the brain and pituitary gland. At the interface, the brain was markedly gliotic with Rosenthal fibers simulating pilocytic astrocytoma. The tumor stroma had reactive changes and commonly showed cyst formation and calcification.

Expression of vascular endothelial growth factor in pediatric and adult cerebral arteriovenous malformations: an immunocytochemical study.

Children and adults may differ with respect to their cerebral vasculature in both normal and pathological states. The authors have identified four pediatric patients in whom a cerebral arteriovenous malformation (AVM) recurred after surgery for removal of the AVM and in whom a normal postoperative angiogram had been obtained. This phenomenon has not been observed in adults. The propensity to regrow a cerebral AVM may reflect a less mature cerebral vasculature and a disregulated angiogenic process. Recently, attention has focused on vascular endothelial growth factor (VEGF) as a possible general mediator of angiogenesis in development and neoplasia. A retrospective immunocytochemical analysis of VEGF expression in AVM tissue was conducted to test the hypothesis that VEGF expression may be found in association with the regrowth of AVMs. The results demonstrate a high degree of astrocytic VEGF expression in four (100%) of four specimens from the initial operation in the children with recurrent AVMs as compared to one (14%) of seven nonrecurrent AVMs in the pediatric and two (25%) of eight adult specimens. All of the specimens from the first operation of the recurrent group demonstrate a clear association of cellular immunoreactivity to the abnormal blood vessels, a relationship that was not observed in the specimens from the nonrecurrent groups. These observations indicate that a humoral mechanism mediated by VEGF may play a role in AVM recurrence.

Determining the maximal length of a vein conduit used as an interposition graft for nerve regeneration.

Although autogenous veins have been used as nerve conduits (AVNCs) both experimentally and clinically for short nerve gaps up to 3 cm, investigators have not as yet determined the maximal effective length for functional nerve regeneration. In addition, the role of the distal nerve stump on subsequent nerve growth remains unclear. A rabbit peroneal nerve AVNC model was used to study axonal regeneration through nerve gaps of 1 to 6 cm. After allowing ample time for nerve regeneration, clinical, electophysiologic and neurohistologic studies were performed to evaluate nerve growth and functional muscle reinnervation. Comparisons were made with 6-cm conventional nerve grafts. Excellent growth and function were found with AVNCs up to 3 cm in length, with increasing incapacity for regeneration at lengths greater than 3 cm. The distal nerve stump is believed to play a vital role in nerve regrowth.

Ganglion cyst of the odontoid process. Case report and review of the literature.

STUDY DESIGN: This case report illustrates that although it is rare, a ganglion cyst can occur intraosseously in the odontoid process. OBJECTIVES: The tissue diagnosis was established by surgical resection of the cyst membrane and evacuation of the cyst content. The patient tolerated the procedure well, and the hospital course was uneventful. SUMMARY OF BACKGROUND DATA: Synovial cyst of the spine is uncommon and is usually found in the lumbar region. Its occurrence in the cervical spine is rare, and no cases in the odontoid process, to the authors' knowledge, have been reported. METHODS: This patient was evaluated initially for neck pain, which led to radiographic studies depicting the lesion. It raised the suspicion of metastatic neoplastic process, although the search for primary source proved to be negative. A biopsy was indicated. RESULTS: Surgical findings consisted of mucoid material field cavity lined by a thin membrane. The cyst was excised, and pathologic evaluation confirmed the diagnosis of synovial cyst. CONCLUSION: The correct radiographic diagnosis of this patient was not made because of lack of experience with such lesions in this location. The authors hope that this case report helps raise the awareness of clinicians in considering this diagnosis when facing similar radiographic presentation.

Pathology of cerebral metastases.

Important pathologic features of cerebral metastases include the route of spread of tumor cells to the brain, differences among metastases based on location in dura mater, leptomeninges, and brain parenchyma, differences based on primary tumor site, both known and unknown, the means of spread of metastases within the brain, and the brain's reactions to metastases. Immunohistochemistry and electron microscopy are increasingly used in the pathologic evaluation of cerebral metastasis.

Mesenchymal chondrosarcoma in anterior skull base: case report.

We report the case of a 16-year-old boy who presented with mesenchymal chondrosarcoma involving the ethmoid sinus, right orbit, nasal cavity, and anterior cranial fossa. The tumor was totally resected by craniofacial surgery; the patient's postoperative course was uneventful. Microscopically, the tumor was composed of highly cellular undifferentiated small cells, alternating with zones of cartilaginous tissues. Mesenchymal chondrosarcoma is a rare, aggressive variant of chondrosarcoma, which might be encountered more frequently due to the advances in neuroimaging and surgical procedures.

Aggressive papillary tumors of the temporal bone: an immunohistochemical analysis in tissue culture.

Aggressive papillary tumors of the temporal bone are neoplasms that are locally invasive and destructive. Previously classified on histologic study as middle ear adenomas or adenocarcinomas, observational evidence suggested that they arose from endolymphatic sac. To evaluate this hypothesis, we established a tissue culture from cells derived from such a papillary tumor and compared immunohistochemical stains of the original tumor with stains on endolymphatic epithelium. Similarities in expression of neuroectodermal antigens were observed. Similar staining antigens in cells derived from tumor and the endolymphatic sac provide evidence that epithelium from endolymphatic sac is the site of origin for these aggressive neoplasms. In tissue culture the cells remain contact inhibited and dependent on serum or growth factors with survival beyond the expected senescence at 30 to 50 generations. Therefore the cell culture technique provides a model for study of the disruption of growth control and invasive properties of this tumor.