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101.
Streptococcus intermedius caused a liver abscess in a patient with chronic granulomatous disease (CGD). In contrast to typical staphylococcal abscesses in CGD, this abscess was liquid, easily drained, and resolved without surgery or steroids. This case and literature review provide insight into this organism's pathogenesis, including in CGD.  相似文献   
102.
Ibrutinib is associated with bleeding-related adverse events of grade ≤2 in severity, and infrequently with grade ≥3 events. To investigate the mechanisms of bleeding and identify patients at risk, we prospectively assessed platelet function and coagulation factors in our investigator-initiated trial of single-agent ibrutinib for chronic lymphocytic leukemia. At a median follow-up of 24 months we recorded grade ≤2 bleeding-related adverse events in 55% of 85 patients. No grade ≥3 events occurred. Median time to event was 49 days. The cumulative incidence of an event plateaued by 6 months, suggesting that the risk of bleeding decreases with continued therapy. At baseline, von Willebrand factor and factor VIII levels were often high and normalized on treatment. Platelet function measured via the platelet function analyzer (PFA-100™) was impaired in 22 patients at baseline and in an additional 19 patients on ibrutinib (often transiently). Collagen and adenosine diphosphate induced platelet aggregation was tested using whole blood aggregometry. Compared to normal controls, response to both agonists was decreased in all patients with chronic lymphocytic leukemia, whether on ibrutinib or not. Compared to untreated chronic lymphocytic leukemia patients, response to collagen showed a mild further decrement on ibrutinib, while response to adenosine diphosphate improved. All parameters associated with a significantly increased risk of bleeding-related events were present at baseline, including prolonged epinephrine closure time (HR 2.74, P=0.012), lower levels of von Willebrand factor activity (HR 2.73, P=0.009) and factor VIII (HR 3.73, P=0.0004). In conclusion, both disease and treatment-related factors influence the risk of bleeding. Patients at greater risk for bleeding of grade ≤2 can be identified by clinical laboratory tests and counseled to avoid aspirin, non-steroidal anti-inflammatory drugs and fish oils. ClinicalTrials.gov identifier NCT01500733  相似文献   
103.

Background

Hemophilia A (HA) is an X-linked inherited bleeding disorder, resulting from a qualitative or quantitative deficiency of clotting factor VIII (FVIII). Antibodies against FVIII, also called inhibitors, block the procoagulant activity of FVIII; thus, impairing hemostatic activity in patients with HA. The exact mechanism underlying the immunological events behind the development of inhibitors remains unknown. This study aimed to understand immune response to FVIII in patients with HA who were either positive [HAα-FVIII(+)] or negative [HAα-FVIII(−)] for inhibitors.

Methods

Cytokine profiles [interferon-γ (IFN − γ), tumor necrosis factor-α (TNF-α), interleukin-4 (IL-4), IL-5, and IL-10] of innate and adaptive immune cells present in the peripheral blood of participants were characterized.

Results

Presence of inhibitors was significantly associated with decreased frequencies of TNF-α-positive monocytes and neutrophils, IL-5-positive monocytes, IL-4-positive neutrophils, and increased frequencies of IL-10-positive neutrophils and T cells. T cells from HAα-FVIII(−) patients expressed increased levels of almost all cytokines. In contrast, HAα-FVIII(+) patients showed lower levels of all cytokines in CD4+ and CD8+ T cells, except IL-10. B cells from HAα-FVIII(−) patients expressed increased levels of IL-4 while those from HAα-FVIII(+) patients expressed increased levels of IL-10.

Conclusions

The global cytokine profiles of innate and adaptive immune cells showed an anti-inflammatory/regulatory pattern in HAα-FVIII(+) patients and a mixed pattern, with a bias toward inflammatory cytokine profile, in HAα-FVIII(−) patients. The occurrence of these profiles seems to be associated with presence FVIII inhibitors.  相似文献   
104.
105.
This report describes the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet production and platelet function in humans. Subjects with advanced solid tumors received PEG-rHuMGDF daily for up to 10 days. There was no increase in circulating platelet count at doses of 0.03 or 0.1 microgram/kg/d by day 12 of study. At doses of 0.3 and 1.0 microgram/kg/d there was a threefold median increase (maximum 10-fold) in platelet count by day 16. The platelets produced in vivo in response to PEG-rHuMGDF showed unchanged aggregation and adenosine triphosphate (ATP)-release responses in in vitro assays. Tests included aggregation and release of ATP in response to adenosine diphosphate (ADP) (10, 5, 2.5, and 1.25 mumol/L), collagen (2 micrograms/mL), thrombin-receptor agonist peptide (TRAP, 10 mumol/L) and ristocetin (1.5 mg/mL). Administration of aspirin to an individual with platelet count of 1,771 x 10(3)/L resulted in the typical aspirin-induced ablation of the normal aggregation and ATP-release response to stimulation with arachidonic acid (0.5 mg/mL), collagen, and ADP (2.5 and 1.25 mumol/L). There was no change in the expression of the platelet-surface activation marker CD62P (P-selectin) nor induction of the fibrinogen binding site on glycoprotein IIb/IIIa as reported by the monoclonal antibody, D3GP3. An elevation of reticulated platelets was evident after 3 days of treatment with PEG-rHuMGDF and preceded the increase in circulating platelet count by 5 to 8 days; this reflected the production of new platelets in response to PEG-rHuMGDF. At later time points, the mean platelet volume (MPV) decreased in a manner inversely proportional to the platelet count. Levels of plasma glycocalicin, a measure of platelet turnover, rose 3 days after the initial increase in the peripheral platelet count. The level of plasma glycocalicin was proportional to the total platelet mass, suggesting that platelets generated in response to PEG-rHuMGDF were not more actively destroyed. Thus, the administration of PEG-rHuMGDF, to humans, increased the circulating platelet count and resulted in fully functional platelets, which showed no detectable increase in reactivity nor alteration in activation status.  相似文献   
106.
Warren  AP; Patel  K; McConkey  DJ; Palacios  R 《Blood》1996,87(9):3676-3687
In our search for cell surface markers expressed on hematopoietic stem cells and/or very early progenitor cells we found that the Joro 177 monoclonal antibody (MoAb) bound to most hematopoietic cells in day 8/8.5 yolk sac, day 12 fetal liver, and day 13 fetal thymocytes; it stained hematopoietic stem cells and less immature lymphoid, myeloid, and erythroid-lineage cells, but not most thymocytes and splenic lymphocytes in adult mice. Joro 177 MoAb stimulated tyrosine phosphorylation of an integral of 124-kD protein and induced homotypic aggregation of lymphoid progenitor cells. Importantly, Joro 177 MoAb inhibited cell survival/growth and consequently the generation of lymphoid, myeloid, and erythroid lineage cells in vitro from early Lin- hematopoietic precursors. Joro 177 MoAb induced apoptosis of hematopoietic progenitor cells. Molecular cloning and expression indicated that Joro 177 MoAb recognizes a type II transmembrane protein, which is the mouse homologue of the human CD98 heavy chain gene. We suggest that CD98 is a cell membrane receptor involved in the control of cell survival/death of hematopoietic cells.  相似文献   
107.
We have examined the value of routine tuberculin testing and BCG vaccination in Edinburgh school children from 1970 to 1983. Over 89,000 children were observed for a mean period of 7 years, during which 77 new cases of tuberculosis were notified in Caucasians. The average annual incidence of tuberculosis in the 65,692 children receiving BCG vaccination at school was 7/10(5), significantly less than the 19/10(5) estimated in 12,987 Heaf negative children who missed BCG vaccination, and the 41/10(5) in 5,308 tuberculin positive children (P less than 0.001). The efficacy of BCG vaccination in this study exceeded 60%. The 5,308 tuberculin positive children were offered chest radiographs with an initial yield (new cases of tuberculosis detected/radiographs taken) of 1/555 for Heaf grade II children, 1/75 for grade III, and 1/25 for grade IV (P less than 0.001). During the period of this study approximately 700 BCG vaccinations were necessary to prevent one new case of tuberculosis and this represents considerably greater benefit than in England and Wales during the same period. There may be a case for continuing the schools' BCG programme in Scotland for a number of years longer than in England and Wales. A national BCG survey for Scotland would be valuable.  相似文献   
108.
We describe three patients with Malpuech syndrome from two families. Previously, 10 patients from 6 families have been reported. Consanguinity in two families suggests autosomal recessive inheritance. Growth retardation, mental retardation, cleft lip, and/or palate, hypertelorism, urogenital abnormalities, and caudal appendage are the key features. Although the spectrum of the features in the reported patients is variable, we do think this syndrome represents a distinct entity. Chromosomal anomalies should be carefully searched for. We discuss differential diagnosis and possible candidate genes and propose diagnostic criteria for Malpuech syndrome.  相似文献   
109.
OBJECTIVE: To evaluate the relative effects of Class II elastics applied directly with utility arches (UAs) or with the Reciprocal Mini-Chin Cup (RMCC) appliance. MATERIALS AND METHODS: Thirty patients with Class II division 1 malocclusion were included. Fifteen of them were treated with the RMCC appliance and the other 15 treated with Class II elastics on UAs. Lateral cephalograms of an additional 15 untreated persons having the same characteristics as the treatment groups were used as a control group. RESULTS: The mean control period was 10 months. Class I molar and canine relationships were achieved in a mean treatment time of 4.6 months with the RMCC appliance and in 8.5 months with the elastics on UAs. The amount of overjet reduction was 4.7 mm in the RMCC group (87.87% dental) and 5.2 mm in the UA group (80.76% dental). The molar correction was 4.5 mm in the RMCC group (87.36% dental) and 2.0 mm in the UA group (51.47% dental). The anterior lower facial height increased in both of the treatment groups. CONCLUSIONS: The RMCC appliance is a valuable alternative for Class II elastic use in Class II cases in which the upper molars need to be moved to the distal more than the upper incisors.  相似文献   
110.

Background

Cutaneous manifestations are early and easily identifiable markers of human immunodeficiency virus (HIV) infection. They can help in predicting severity and progress of the disease and can be correlated well with CD4 counts. This study was undertaken to study the cutaneous manifestations of HIV infection and to correlate them with CD4 counts. It also aimed to study the changing spectrum of these manifestations and describe cutaneous manifestations seen in advanced disease.

Method

A total of 234 HIV-positive patients not on anti-retroviral therapy, who attended the outpatient department or were admitted as inpatients at Military Hospital, Shillong during the period between May 2008 and October 2009 were included. Cutaneous, mucosal, and genitourinary manifestations in these patients were studied in detail and were correlated with CD4 counts.

Results

Infections were the most common group of mucocutaneous manifestations, while onychomycosis was the commonly observed individual manifestation. A different set of cutaneous markers for advanced HIV disease was observed and new parameters for therapy were also arrived at.

Conclusion

Specific morphological variants of cutaneous markers may provide a better clue to early diagnosis of HIV and can help in diagnosing advanced stages of the disease. Fresh cutaneous markers are required for indicating cut-off levels of CD4 count at 350/μL for starting therapy.  相似文献   
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