摘要:

The monocyte-osteoclast hypothesis states that osteoclasts are derived from the differentiation of monocytes. Recently we reported that the U937 cell line, a monoblastic cell of human origin, differentiated to an osteoclast precursor when cultured in the presence of 1,25-dihydroxyvitamin D3(1,25(OH)2D3) and lymphokines. Using this model of monocytic differentiation we have tested the role of calcium (Ca) in the culture medium by the addition of CaCl2in the presence or absence of EGTA, a chelating agent, on the growth and differentiation of the U937 cells. Increasing the Ca concentration ([Ca]) to 2.0 mM inhibited the differentiation of resting or 1,25(OH)2D3exposed cells, but had no effect on the cells exposed to lymphokines or lymphokines and 1,25 (OH)2D3. Reducing the [Ca] to 10−7M inhibited differentiation but also reduced cell viability. Addition of CaCl2to medium containing EGTA to produce [Ca] in the range of 10−5M to 10−3M restored the cellular growth and viability. Inhibition of differentiation associated with the reduced calcium concentration over the range of 10−5M to 10−3M was not due to growth inhibition. These findings show the importance of the extracellular [Ca] in an in vitro model of monocytic differentiation induced by vitamin D and lymphokines.

ISSN:0002-9629    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

Rabbits exposed to paraquat develop interstitial pneumonitis. A sublethal dose of paraquat (PQ) solution (250 mg/100 ml) was aerosolized by ultrasonic nebulization for one hour to rabbits in a closed vented chamber on two occasions with a five-day interval between exposures. Groups studied included saline-exposed (N = 4); saline-exposed, methylprednisolone (MP) treated (1 mg/kg daily IM starting one day prior to the first exposure and then throughout the exposure period until sacrifice at day 8) (N=4); PQ-exposed (N=6); and PQ-exposed, MP treated (N = 6). Controls and MP controls gained weight and showed no abnormalities of respiratory rate. PQ and PQ-MP animals lost weight (average −0.35 kg) and had decreased breathing frequency (average decrease, 80–90 BPM). Blood gases showed minimal changes in all groups, although some individuals had hypoxemia and an increased alveolar-arterial oxygen pressure quotient [P(A-a)O2]. Bronchoalveolar lavage at sacrifice showed a marked increase in the percent of neutrophils in PQ and PQ-MP animals that correlated with pathology scores (R = 0.83). The P(A-a)O2correlated with both the percent of neutrophils in lavage and the pathology score. Total cells recovered from a 100 ml lavage were comparable in all groups (approximately 3 × 107cells). Steroid did not prevent the development of pathologic change.

ISSN:0002-9629    

出版商:OVID    

年代:1985

数据来源: OVID

ISSN:0002-9629    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

NontypableHaemophilus influenzaeis a normal inhabitant of the upper respiratory tract and a common pathogen in diseases limited to mucosal surfaces. NontypableH. influenzaehas only occasionally been reported to cause invasive disease locally or systemically. In a period of two years, three patients of 17 with positive blood cultures forH. influenzaewere found to have nontypable strains, two of which were resistant to ampicillin. The presumed sites of entry were an oral mucosal lesion, sinus mucosa, and female genital tract. All three patients responded rapidly to antibiotics to which their isolates were susceptible.

ISSN:0002-9629    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

We postulate that the previously healthy woman reported here developed abnormal host defense mechanisms because of acute renal failure, metabolic acidosis, hyperglycemia, and glucocorticosteroid administration. Pneumonia unresponsive to antibiotics terminated in massive fatal hemoptysis that was due to mucormycosis with rupture of the pulmonary artery into the tracheobronchial tree.

ISSN:0002-9629    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

A man developed acute monoarticular ankle arthritis caused by calcium pyrophosphate dihydrate (CPPD) crystals. The clinical syndrome resembled that of a pyogenic arthritis. Synovial fluid analysis revealed a glucose concentration of 13 mg/dL and 99,000 white blood cells/mm3. Only one other report of an extremely low synovial fluid glucose associated with pseudogout could be found.The diagnosis of pseudogout was initially suggested when rhomboidal forms were seen during synovial fluid Gram stain examination. Synovial fluid examination with polarized microscopy was initially negative, but revealed numerous CPPD crystals when repeated on the third hospital day.This case serves to illustrate how pseudogout can mimic pyogenic arthritis in both clinical presentation and low synovial fluid glucose concentration. The examination of Gram-stained synovial fluid can reveal the rhomboidal forms of CPPD crystals. The appearance of these crystals is documented in this report.

ISSN:0002-9629    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

Although a number of studies have suggested that granulocyte sequestration is an important pathophysiologic event in ARDS, histologic evidence of aggregated granulocytes in the pulmonary microvasculature is limited, and serial histologic data have not been reported with physiologic measurements. We report a patient with ARDS who demonstrated microvascular granulocyte aggregation and lung edema in sections of a lung biopsy obtained seven days after the onset of symptoms. Pulmonary vascular resistance and pulmonary capillary wedge pressure were normal immediately before the biopsy. A second biopsy performed 12 days later showed decreased lung edema and no evidence of intravascular leukostasis. This case provides histologic support for the hypothesis that granulocyte aggregates contribute to pulmonary edema associated with ARDS.

ISSN:0002-9629    

出版商:OVID    

年代:1985

数据来源: OVID

ISSN:0002-9629    

出版商:OVID    

年代:1985

数据来源: OVID