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991.
Neurological disorders are a major threat to public health. Stem cell‐based regenerative medicine is now a promising experimental paradigm for its treatment, as shown in pre‐clinical animal studies. Initial attempts have been on the replacement of neuronal cells only, but glial progenitors (GPs) are now becoming strong alternative cellular therapeutic candidates to replace oligodendrocytes and astrocytes as knowledge accumulates about their important emerging role in various disease processes. There are many examples of successful therapeutic outcomes for transplanted GPs in small animal models, but clinical translation has proved to be challenging due to the 1,000‐fold larger volume of the human brain compared to mice. Human GPs transplanted into the mouse brain migrate extensively and can induce global cell replacement, but a similar extent of migration in the human brain would only allow for local rather than global cell replacement. We review here the mechanisms that govern cell migration, which could potentially be exploited to enhance the migratory properties of GPs through cell engineering pre‐transplantation. We furthermore discuss the (dis)advantages of the various cell delivery routes that are available, with particular emphasis on intra‐arterial injection as the most suitable route for achieving global cell distribution in the larger brain. Now that therapeutic success has proven to be feasible in small animal models, future efforts will need to be directed to enhance global cell delivery and migration to make bench‐to‐bedside translation a reality.  相似文献   
992.
Honey-bee bites which require urgent hospitalization is very rare. It is mainly seen as occupational hazards in farmers, tree dwellers and honey collectors. Common clinical presentation includes minor localized reactions in form of swelling and redness sometimes anaphylactic reaction. Infrequent major complications reported from different studies include rhabdomyolysis, acute renal failure (ARF), acute pulmonary edema, intravascular coagulation, encephalopathy and very rarely cerebral haemorrhage. Stroke due to multiple intra- cerebral infarcts along with rhabdomyolysis in patient of honey-bee bite is rare neurological complication. We report a case of 70 year man with honey-bee bite and multiple intracerebral infarcts presented as stroke, and rhabdomyolysis and ARF. When a patient presented with honey-bee bite, one should suspect serious complications. Despite advances in the understanding of pathophysiology its complications remains enigmatic and in some instances may be multifactorial. Various therapeutic interventions if started early after diagnosis reduces the possible consequences as potential reversibility of the illness.  相似文献   
993.
Human kidney hexosaminidase A (beta-N-acetylglucosaminidase; 2-acetamido-2-deoxy-beta-D-glucoside acetamidodeoxyglucohydrolase; EC 3.2.1.30) is a heteropolymer of two immunologically distinct subunits designated as alpha and beta. Hexosaminidase B, however, is a homopolymer comprised entirely of beta subunits. When human kidney hexosaminidase A was dissociated into its subunits by p-hydroxymercuribenzoate, three distinct proteins having isoelectric points of pH 7.2.5.4, and 4.3 were isolated. The fraction having an isoelectric point of pH 7.2, designated as beta fraction, was electrophoretically and immunologically identical to hexosaminidase B and was enzymatically active. The proteins having isoelectric points of pH 5.4 and 4.3, designated as hexosaminidase Ai and alpha fractions, respectively, were enzymatically inactive and crossreacted with antiserum against hexosaminidase A and not with antiserum against hexosaminidase B. Upon incubation of p-hydroxymercuribenzoate-treated hexosaminidase A with dithiothreitol,, hexosaminidase A activity, as well as antigenicity, was regenerated, indicating that alpha and beta subunits hybridize to form hexosaminidase A. Antibodies raised in rabbits against beta fractions reacted with both hexosaminidase A and B, whereas the antibodies against alpha and hexosaminidase Ai fractions reacted only against hexosaminidase A. This would indicate that both fractions are composed only of subunits unique to hexosaminidase A. The molecular weights of alpha,beta, and hexosaminidase Ai fractions were estimated to be 47,000, 120,000, and 180,000 respectively, by Sephadex gel filtration. Upon urea-sodium dodecyl sulfate polyacrylamide electrophoresis, each of the three fractions dissociated into a single polypeptide having a molecular weight of approximately 18,000. It is concluded that p-hydroxymercuribenzoate dissociates hexosaminidase A, (alphabeta)3, into its subunits, and the beta subunits can reassociate to form relatively stable hexosaminidase B, (betabeta)3, while the alpha subunits reassociate in both the dimeric state, alpha2, and a polymeric state, alpha8.  相似文献   
994.
Of 132 children with bladder stones seen in 1 year, 94% were boys and 73% were aged between 1 and 5 years. Significant malnutrition and evidence of vitamin deficiency were absent. Wheat bread was the dietary staple, while the intake of milk and dairy products, eggs and meat was very low. Analysis of 29 stones showed them to consist mainly of calcium oxalate and uric acid, with small amounts of calcium phosphate and magnesium ammonium phosphate in some cases. The composition of the surface and central parts of the stones, examined in 20 cases, was usually different. The nucleus was formed almost entirely of calcium oxalate and uric acid in four and three cases respectively, whereas the surface layers were composed of other ingredients. In another case the nucleus was composed entirely of xanthine, which indicated a diagnosis of xanthinuria.  相似文献   
995.
The expression of progenitor cell associated antigen CD34 was investigated in cells from 28 patients with chronic myeloid leukemia (CML). The CD34 positivity varied from 0-26% in patients with chronic phases CML (n = 17); from 6-64% in patients with accelerated phase CML (n = 4); and from 27-97% in the patients with blastic crisis of CML (n = 8). The difference in CD34 positivity between chronic (mean 10.1 +/- 2.3%), accelerated (37.7 +/- 13.3%) and blastic (58.0 +/- 7.3%) phases of CML is statistically significant (p less than 0.05), however, the number of patients studied, especially in accelerated and blastic phases is very small. There was no difference in the CD34 positivity of the cells in the peripheral blood and in the bone marrow. CD34 positivity was higher in patients with chronic phase CML at diagnosis (untreated patients) than in those who were studied during treatment. The possible importance of serially studying CD34 positivity in patients with CML is discussed in the paper.  相似文献   
996.
The alterations in serum levels of T3, T4, TSH and TBG, TSH response to 100 mug iv TRH, and urinary excretion of T3 and T4 were studied in 8 healthy men at sea level (SL), on days 1, 2, 4, 8 and 16 after arrival by air at high altitude (3,700 m, HA), and during days 5 to 7 after their return to SL. No significant alterations in serum levels of TSH and TBG or TSH response to TRH were observed during exposure to HA or on return to SL. There was, however, an acute elevation in both serum total T3 and T4. Serum total T3 from a mean basal+/-SE value of 128+/-13 ng/dl increased to 320+/-18 on day 1 and remained significantly elevated at 225+/-48 up to day 8 after arrival at high altitude. Similarly serum total T4 increased from basal level of 9+/-0.92 mug/dl to 15.2+/-1.2 and remained elevated till day 16 and it was 11+/-1.19 mug/dl during days 5 to 7 after return to SL. The urinary excretion of both T3 and T4 was decreased. These changes perhaps were the result of complex physiologic adjustments on acute exposure to high altitude, like shrinkage of the T3 and T4 distribution pools, altered binding capacities of thyroid hormones binding proteins, and a reduction in clearance of thyroid hormones from the plasma compartment; and were probably not suggestive of an enhanced thyroid activity. Their actual significance in high altitude adaptation in man is not clearly understood.  相似文献   
997.
The aim of this study was to describe the clinical profile of children with congenital pigmentary anomalies along Blaschko lines and the associated manifestations in the central nervous system. Twenty-six children aged 12 years or less (14 boys and 12 girls), with hypopigmentation and hyperpigmentation along Blaschko lines and central nervous system manifestations were included during the period June 2001 to December 2003. Detailed physical, cutaneous, and systemic examinations were carried out. Relevant investigations included histopathology, karyotyping, electroencephalogram, computerized tomography scans, and magnetic resonance imaging of the brain whenever possible. Twenty children had hyperpigmentation along the lines of Blaschko, four had hypopigmentation, and two had a combination of the two. Eight children had diffuse involvement. Of these, two each had hypomelanosis of Ito, incontinentia pigmenti and linear and whorled nevoid hypermelanosis. The remaining 20 patients could not be categorized as any of the described entities. The majority (92.3%) of patients manifested skin and central nervous system disorders before the age of 2 years. Hyperpigmentation along Blaschko lines was significantly higher in patients with central nervous system manifestations (p = 0.01). Developmental delay was the most frequent central nervous system presentation. Multiple systems were affected, including the eyes. Histology was useful to distinguish incontinentia pigmenti from other types of nevoid hyperpigmentation.  相似文献   
998.
A healthy elderly man presented with localized isolated erythematous tender, anesthetic, oval plaque with little scaling near the medial angle of right eye, of 3 years' duration without any obvious nerve thickening, treated irregularly with WHO MDT for 3 months, clinically simulating BT leprosy with downgrading reversal reaction. Histology showed a BL granuloma with plenty of solid staining AFB within the foamy macrophages. Lepromin test was very weakly positive. The case is discussed in the light of clinicohistological disparity in leprosy cases with review of relevant literatures. A stress is laid on the importance of newer MDT in such cases to prevent drug-resistance, relapse and recurrence.  相似文献   
999.
Tilorone, which is 2,7-bis[2-(diethylamino)ethoxy]-9H-fluoren-9-one dihydrochloride, and 13 of its analogs inhibited human cellular DNA polymerases alpha and beta assayed with activated DNA as template and also cellular DNA polymerase gamma and DNA polymerase from simian sarcoma virus assayed with poly(A) (dT)12-18 as template. Terminal deoxynucleotidyltransferase (TdT), which has no template requirement, was not inhibited by any of the 14 compounds when d(A)12-18 or d(G)12-18 was used as initiator. Three compounds did not inhibit TdT assayed with activated DNA as initiator, but 11 compounds did, and these 11 compounds were generally less inhibitory to TdT than to the other DNA polymerases. The three compounds that did not inhibit TdT assayed with activated DNA but did inhibit the other DNA polymerases will be useful in the characterization of TdT activity. Modifications of the polycyclic ring structure of tilorone and the kinds of substituent groups attached to the ring structures influenced the degree of inhibition of all enzymes.  相似文献   
1000.
Objectives: The characteristics of patients with Acute Respiratory Distress Syndrome (ARDS) as a complication of Babesia microti infection have not been systematically described.

Methods: Adult patients admitted to the medical intensive care unit (MICU) of a tertiary care hospital in the Lower Hudson Valley of New York from 1/1/2008 to 8/1/2016 were evaluated for ARDS complicating babesiosis.

Results: Of 22 patients with babesiosis in the MICU, eight (36.4%; 95% CI: 19.7–57.0%) had ARDS. Six patients (75%) developed ARDS following initiation of anti-babesia drug therapy; however, the mean duration of symptoms in these patients exceeded that of patients who developed ARDS prior to initiation of treatment (7.50 ± 3.83d vs. 4.50 ± 0.71d, p = 0.34). Three patients (37.5%; 95% CI: 13.7–69.4%) expired without recovery from ARDS. In comparison, the mortality rate for the 14 MICU babesiosis patients without ARDS was 14.3% (p = 0.31). There was a trend toward younger age in survivors relative to non-survivors (mean age 54.6 ± 13.8y vs. 74.0 ± 6.24y, p = 0.07). Three of the five survivors did not require mechanical ventilation. The mean sequential organ failure assessment score of non-survivors was significantly higher than that of survivors (12.3 ± 1.15 vs. 6.0 ± 1.4, p = 0.0006).

Conclusion: Among 22 critically ill adult patients with B. microti infection, ARDS developed in eight (35.4%), and three (37.5%) expired without resolution of the ARDS. ARDS often followed the initiation of anti-babesia drug therapy, raising the question of whether the death of the parasite per se contributed to its development. However, this observation was confounded by the longer duration of symptoms preceding initiation of drug therapy.  相似文献   

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