Modified orthodontic treatment goals in a patient with multiple complicating factors

This paper reviews orthodontic care in patients who are in non-traditional categories. Specific orthodontic management of a patient who had severe hemophilia, seropositivity for anti-HIV Ab, and Hepatitis B surface antigen is reviewed. The Importance of defining acceptable treatment goals in these patients is of paramount Importance.     

Improved stool concentration procedure for detection of Cryptosporidium oocysts in fecal specimens.

Epidemiologic and laboratory data suggest that coprodiagnostic methods may fail to detect Cryptosporidium oocysts in stool specimens of infected patients. To improve the efficacy of stool concentration procedures, we modified different steps of the Formalin-ethyl acetate (FEA) stool concentration technique and evaluated these modifications by examining stool samples seeded with known numbers of Cryptosporidium oocysts. Because these modifications failed to improve oocyst detection, we developed a new stool concentration technique that includes FEA sedimentation followed by layering and flotation over hypertonic sodium chloride solution to separate parasites from stool debris. Compared with the standard FEA procedure, this technique improved Cryptosporidium oocyst detection. The sensitivities of the two concentration techniques were similar for diarrheal (watery) stool specimens (100% of watery stool specimens seeded with 5,000 oocysts per g of stool were identified as positive by the new technique, compared with 90% of stools processed by the standard FEA technique). However, the most significant improvement in diagnosis occurred with formed stool specimens that were not fatty; 70 to 90% of formed stool specimens seeded with 5,000 oocysts were identified as positive by the new technique, compared with 0% of specimens processed by the standard FEA technique. One hundred percent of formed specimens seeded with 10,000 oocysts were correctly diagnosed by using the new technique, while 0 to 60% of specimens processed by the standard FEA technique were found positive. Similarly, only 50 to 90% of stool specimens seeded with 50,000 oocysts were identified as positive by using the standard FEA technique, compared with a 100% positive rate by the new technique. The new stool concentration procedure provides enhanced detection of Cryptosporidium oocysts in all stool samples.     

Transfusion of bone marrow red cells during bone marrow harvests

Large volumes of bone marrow may be required for certain types of autologous bone marrow transplants. The present study was done to determine whether red cells obtained during a bone marrow harvest would be useful in reducing homologous transfusion requirements. A group of patients receiving standard transfusion support during the harvest (group 1) was compared to a group that received processed bone marrow red cells (PBMRBC) (group 2). Using the Cobe 2991 cell processor, 90% of the harvested bone marrow red cells were extracted and transfused during the procedure. Group 2 received a median of 1500 ml of blood processed from the bone marrow or 413 ml (volume of marrow processed x hematocrit) of red cells. Infusion of the PBMRBC reduced the homologous transfusion requirement from 6.5 units to 3.0 units (p = 0.02). In addition, group 1 had a 20% decrease in hematocrit following transfusion compared to the pre-harvest hematocrit, as opposed to an 8% decrease in group 2 (p = 0.02). This study indicates that PBMRBC can reduce the homologous transfusion requirements during an autologous bone marrow harvest.     

Disseminated microsporidiosis (Encephalitozoon hellem) and acquired immunodeficiency syndrome. Autopsy evidence for respiratory acquisition.

Microsporidia are obligate intracellular protozoal parasites that infect a variety of cell types in a broad range of invertebrates and vertebrates. They have recently come to medical attention due to the increased frequency with which members of two microsporidian genera, Enterocytozoon and Encephalitozoon, are being diagnosed in patients with the acquired immunodeficiency syndrome (AIDS). The majority of published reports of human microsporidiosis describe Enterocytozoon infection of small intestinal enterocytes. In addition, a growing number of AIDS patients have been identified with infection due to the two species of Encephalitozoon-Encephalitozoon cuniculi and Encephalitozoon hellem, observed in conjunctival, corneal, and, recently, sinonasal tissues. However, there are scant data regarding the systemic pathology and epidemiology of these infections. This article describes a patient with AIDS who died with systemic Encephalitozoon infection. The etiologic microsporidian was found to be E hellem by using antemortem biochemical and antigenic analyses. A complete autopsy, the first to be reported in a patient with this infection, revealed organisms in the eyes, urinary tract, and respiratory tract. A surprising observation was the occurrence of numerous organisms within the lining epithelium of almost the entire length of the tracheobronchial tree, suggestive of respiratory acquisition. Detailed light and electron microscopic findings and the biological and diagnostic features of microsporidiosis are discussed.     

Dissociation of the Medial Prefrontal, Posterior Parietal, and Posterior Temporal Cortex for Spatial Navigation and Recognition Memory in the Rat

Rats with lesions of the medial prefrontal, posterior parietal,or posterior temporal cortex were tested in five spatial navigationtasks, which varied in egocentric or allocentric demands, avisual discrimination task, and two delayed nonmatching-to-sampletasks. Rats with prefrontal lesions were impaired at every spatialnavigation task, whereas rats with posterior parietal lesionshad selective spatial navigation impairments. Rats with prefrontallesions were also impaired at a visual delayed nonmatching-to-sampletask, as they were unable to learn the task, even with no delay.The results are consistent with the idea that the basic planof mammalian cortex includes prefrontal, posterior parietal,and posterior temporal regions, each of which have generallysimilar functions across mammalian taxa. There are, however,species-typical differences that reflect specific ecologicalpressures on the development of the different regions.     

Frame-based immobilization and targeting for stereotactic body radiation therapy.

Frame-based stereotactic body radiation therapy (SBRT), such as that conducted with Elekta's Stereotactic Body Frame, can provide an extra measure of precision in the delivery of radiation to extracranial targets, and facilitates secure patient immobilization. In this paper, we review the steps involved in optimal use of an extra-cranial immobilization device for SBRT treatments. Our approach to using frame-based SBRT consists of 4 steps: patient immobilization, tumor and organ motion control, treatment/planning correlation, and daily targeting with pretreatment quality assurance. Patient immobilization was achieved with the Vac-Loc bag, which uses styrofoam beads to conform to the patient's shape comfortably within the body frame. Organ and motion control was assessed under fluoroscopy and controlled via a frame-mounted abdominal pressure plate. The compression screw was tightened until the diaphragmatic excursion range was < 1 cm. Treatment planning was performed using the Philips Pinnacle 6.2b system. In this treatment process, a 20 to 30 noncoplanar beam arrangement was initially selected and an inverse beam weight optimization algorithm was applied. Those beams with low beam weights were removed, leaving a manageable number of beams for treatment delivery. After planning, daily targeting using computed tomography (CT) to verify x-, y-, and z-coordinates of the treatment isocenter were used as a measure of quality assurance. We found our daily setup variation typically averaged < 5 mm in all directions, which is comparable to other published studies on Stereotactic Body Frame. Treatment time ranged from 30 to 45 minutes. Results demonstrate that patients have experienced high rates of local control with acceptable rates of severe side effects - by virtue of the tightly constrained treatment fields. The body frame facilitated comfortable patient positioning and quality assurance checks of the tumor, in relation to another set of independent set of coordinates defined by the body frame fiducials. The ability to impose abdominal compression proved to be a simple way to reduce target and tissue motion. SBRT with Stereotactic Body Frame enables comfortable patient immobilization and facilitates repeated registering and re-registering of the patient to the frame. With the body frame, large-dose-per fraction treatment is possible for localized tumor deposits with the aim of attaining a more therapeutic result.