Erythrocytes as carriers of chemotherapeutic agents for targeting the reticuloendothelial system

The object of this work was to define a model using hypotonically loaded erythrocytes as a vehicle to target drugs to the reticuloendothelial system (RES). The optimum hemolytic event was found to occur at 100 mOsm/kg using a 0.5-min exposure at 0 degrees C. Approximately one third of the total volume of the cells could be replaced with hypotonic drug solutions under these conditions. Although cytosine-beta-D-arabinofuranoside, ara C, is membrane permeable and could not be entrapped in the erythrocytes, phosphorylation of this nucleoside antimetabolite enabled it to be loaded efficiently. Actinomycin D could be loaded and retained within the cells at 0 degrees C, but 90% of this loaded drug leaked out of the erythrocytes in 1 min at 37 degrees C. Actinomycin D-DNA complexes, however, could be loaded and retained for longer periods. In this case, 50% of the DNA-bound drug was retained in the cells for one hour at 37 degrees C. It was found that the glycopeptide antitumor antibiotic, bleomycin, could be entrapped and retained in the cells without appreciable leakage. It was possible to load a human therapeutic dose of this drug in 1-2 ml of packed cells. Furthermore, it was demonstrated that bleomycin entrapped in erythrocytes was significantly more effective than the same dose of free drug in suppressing the phagocytic function of the RES in Balb/C and C3H mice. The rationale is discussed for the possible use of these drugs, entrapped in erythrocytes, for the production of RES blockade in the treatment of disorders in man.     

Non-dysraphic intramedullary spinal cord lipoma

True intramedullary spinal cord lipomas are extremely rare. Two cases of intramedullary spinal cord lipoma are presented. The patients did not exhibit any form of spinal dysraphism. The patients presented with gait difficulty, upper limb weakness, sphincter disturbance, dysesthesias and neck pain. The tumors were removed sub-totally and the neurological grade improved postoperatively in one of the patients.     

Normal range determination of lymphocytes subsets in normal adults in Iran

Immunophenotyping of lymphocytes is very essential for evaluation of immune system. Due to the effect of environmental factors and ethical diversity on immune system, establishment of an internal normal range of lymphocyte subsets is a necessity for each population. The aim of this study was to determine the normal range of T and B lymphocytes, and NK cells in normal Iranian adults. Two hundred and thirty three Iranian normal adult volunteers took part in this study. Complete Blood Count (CBC) was performed for them with Sysmex (KX21) and cells with CD3, CD4, CD8, CD19 and CD16/56 surface markers were simultaneously detected by flow cytometry method with FACstar system. Their percentile and absolute count were determined.The volunteers were 150 male and 83 female. Mean percentages of lymphocyte subpopulation were: CD3 (67.66 ±7.76), CD19 (14.41±5.09), CD4 (39.22±6.7), CD8 (25.42 ±5.4) and CD16/56 (10.14±6.42). Also, their mean absolute count of lymphocyte bearing CD3, CD19, CD4 and CD8 were 1,504±505/μl, 332±186/μl, 827±313/μl and 522±185/μl, respectively.Our results are comparable with similar Asian results from other Asian population, but are different from European population, we therefore conclude that it is necessary for each laboratory to establish an internal normal range for the lymphocytes bearing above- mentioned markers.     

Cerebellar tuberculoma mimicking posterior cranial fossa tumour

A young girl presented with history of prolonged fever, vomiting and headache. CT scan of brain revealed a space occupying lesion in posterior cranial fossa with moderate hydrocephalus. Surgery was performed and histopathology report confirmed the lesion as tuberculous. Patient showed smooth postoperative recovery and complete remission of complaints on antituberculous treatment for one year and regular follow-up.     

Detection of <Emphasis Type="BoldItalic">Cryptosporidium parvum</Emphasis> and <Emphasis Type="BoldItalic">Cryptosporidium hominis</Emphasis> in human patients in Cairo,Egypt

Cryptosporidium is a significant cause of diarrheal disease in developing and industrialized nations. Cryptosporidium hominis and Cryptosporidium parvum are the main agents of cryptosporidiosis in humans. In Egypt, very little is known about genetic structure of Cryptosporidium spp. Therefore, this study was designed to examine samples from sporadic cases of cryptosporidiosis in Egyptians in order to identify the species involved in infection as well as the transmission dynamics and distribution of the parasite in the Great Cairo area. A total of 391 human faecal samples were collected, between May 2008 and March 2009, from ten public hospitals in Great Cairo. Initial screening by immunochromatographic detection kit “the Stick Crypto-Giardia; Operon” showed 23 possible positive cases. Twenty of them were confirmed by microscopic examination. PCR was performed by amplification of the oocyst wall protein (COWP) gene where 18 out of 23 samples were positive, one not detected by microscopy. Cryptosporidium genotyping was performed by RFLP analysis of PCR products of the diagnosis PCR. Only 15 samples rendered a digestion pattern. The genotyping distribution was nine cases showing C. hominis genotype, three showing C. parvum genotype and three showing mixed infection by C. hominis and C. parvum. The data showed an elevated prevalence of C. hominis (80.0%), the most anthroponotic species, suggesting a human–human transmission. Furthermore, the presence of up to 40% of samples infected with C. parvum shows that further investigations are required to determine the subgenotypes of C. parvum to clarify the mode of transmission in order to improve the control measures.     

A review of gait disorders in the elderly and neurological patients for robot-assisted training

Abstract

Purpose: Ambulation is an important objective for people with pathological gaits. Exoskeleton robots can assist these people to complete their activities of daily living. There are exoskeletons that have been presented in literature to assist the elderly and other pathological gait users. This article presents a review of the degree of support required in the elderly and neurological gait disorders found in the human population. This will help to advance the design of robot-assisted devices based on the needs of the end users.

Methods: The articles included in this review are collected from different databases including Science Direct, Springer Link, Web of Science, Medline and PubMed and with the purpose to investigate the gait parameters of elderly and neurological patients. Studies were included after considering the full texts and only those which focus on spatiotemporal, kinematic and kinetic gait parameters were selected as they are most relevant to the scope of this review. A systematic review and meta-analysis were conducted.

Results: The meta-analysis report on the spatiotemporal, kinematic and kinetic gait parameters of elderly and neurological patients revealed a significant difference based on the type and level of impairment. Healthy elderly population showed deviations in the gait parameters due to age, however, significant difference is observed in the gait parameters of the neurological patients.

Conclusion: A level of agreement was observed in most of the studies however the review also noticed some controversies among different studies in the same group. The review on the spatiotemporal, kinematics and kinetic gait parameters will provide a summary of the fundamental needs of the users for the future design and development of robotic assistive devices.

• Implications for rehabilitation

• The support requirements provide the foundation for designing assistive devices.

• The findings will be crucial in defining the design criteria for robot assistive devices.

     

The effect of antilymphocytic antibody on the humoral immune response in different strains of mice: III. The response to type III pneumococcus polysaccharide

The effect of a single batch of horse anti-mouse thymocyte globulin on the immune response to type III polysaccharide antigen has been investigated in 2–3-month-old male A/HeJ, C₅₇B1, BALB/c, DBA/1, CBA and C₃H mice. In almost all cases the intraperitoneal administration of 5 mg of this material on days –4 and –2 significantly suppressed the immune response to 0.1, 1.0 and 5.0 μg of antigen injected i.v. on day 0. Further studies undertaken in BALB/c mice indicated that effective suppression of the immune response to type III polysaccharide antigen could also be achieved by injecting 5 mg of this product (i.p.) some 15–30 minutes prior to antigenic challenge. Preliminary cell reconstitution studies in antilymphocytic antibody-treated CBA mice indicate that the ability to respond to type III polysaccharide can be partially restored by the injection of syngeneic thymocytes, bone marrow cells or spleen cells.     

Longitudinal Positron Emission Tomography in Preventive Alzheimer's Disease Drug Trials,Critical Barriers from Imaging Science Perspective

Recent Alzheimer's trials have recruited cognitively normal people at risk for Alzheimer's dementia. Due to the lack of clinical symptoms in normal population, conventional clinical outcome measures are not suitable for these early trials. While several groups are developing new composite cognitive tests that could serve as potential outcome measures by detecting subtle cognitive changes in normal people, there is a need for longitudinal brain imaging techniques that can correlate with temporal changes in these new tests and provide additional objective measures of neuropathological changes in brain. Positron emission tomography (PET) is a nuclear medicine imaging procedure based on the measurement of annihilation photons after positron emission from radiolabeled molecules that allow tracking of biological processes in body, including the brain. PET is a well‐established in vivo imaging modality in Alzheimer's disease diagnosis and research due to its capability of detecting abnormalities in three major hallmarks of this disease. These include (1) amyloid beta plaques; (2) neurofibrillary tau tangles and (3) decrease in neuronal activity due to loss of nerve cell connection and death. While semiquantitative PET imaging techniques are commonly used to set discrete cut‐points to stratify abnormal levels of amyloid accumulation and neurodegeneration, they are suboptimal for detecting subtle longitudinal changes. In this study, we have identified and discussed four critical barriers in conventional longitudinal PET imaging that may be particularly relevant for early Alzheimer's disease studies. These include within and across subject heterogeneity of AD‐affected brain regions, PET intensity normalization, neuronal compensations in early disease stages and cerebrovascular amyloid deposition.