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Biomedical subjects

R Jaffe

Publications and source records attributed to R Jaffe.

At least 19 recordsLinked to original sources
PubMed1997

Contemporary classification of histiocytic disorders. The WHO Committee On Histiocytic/Reticulum Cell Proliferations. Reclassification Working Group of the Histiocyte Society.

Pathologists and pediatric hematologist/ oncologists of the World Health Organization's Committee on Histiocytic/Reticulum Cell Proliferations and the Reclassification Working Group of the Histiocyte Society present a classification of the histiocytic disorders that primarily affect children. Nosology, based on the lineage of lesional cells and biological behavior, is related to the ontogeny of histiocytes (macrophages and dendritic cells of the immune system). Dendritic cell-related disorders of varied biological behavior are dominated by Langerhans cell histiocytosis, but separate secondary proliferations of dendritic cells must be differentiated. Juvenile xanthogranuloma represents a disorder of dermal dendrocytes, another dendritic cell of skin. The hemophagocytic syndromes are the most common of the macrophage-related disorders of varied biological behavior. Guidelines for distinguishing the exceedingly rare malignant diseases of histiocytes from large cell lymphomas through the use of a battery of special studies are provided.

Cell Lineage↗
PubMed1997

Maternal circulation in the first-trimester human placenta--myth or reality?

The classic theory of development of the uteroplacental and intervillous circulation determined that maternal blood enters the intervillous space in high-pressure streams from the early first trimester. This theory has recently been challenged and our hypothesis to be presented is that the intervillous circulation is not fully established until the end of the first trimester. Ex vivo studies of hysterectomy specimens have demonstrated that trophoblastic plugs obstruct blood flow into the intervillous space in early pregnancy and only at 12 to 13 weeks do these plugs become loose and allow for continuous maternal blood flow into the intervillous space. This concept is supported by many other experimental findings. In complicated early pregnancies the uteroplacental circulation demonstrates flow characteristics that are strikingly different from those of normal early pregnancies. In abnormal pregnancies increased flow within the intervillous space is demonstrated by color Doppler imaging. Our hypothesis supports other studies that have shown that the embryo favors an environment low in oxygen during early development and that oxygen levels in placental tissue are low in the early first trimester. The classic drawing of placental circulations is based on second- and third-trimester studies, and its applicability to the early first trimester should be revisited because we will show that new data support the hypothesis that the development of the early intervillous circulation is a progressive phenomenon.

Chorionic Villi↗
PubMed1997

Renal microcirculation and tissue damage during acute ureteral obstruction in the rat: effect of saline infusion, indomethacin and radiocontrast.

Radiocontrast agents and nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used for the diagnosis and treatment of renal colic. We studied their impact during unilateral acute urinary outflow obstruction upon renal microcirculation and parenchymal integrity. Laser-Doppler and ultrasonic regional flow measurements demonstrated selective decline of outer medullary blood flow by 23 +/- 2% during an acute increase of intra-pelvic pressure to 50 to 55 cm H2O (N = 28, X +/- SEM, P < 0.01). In rats preconditioned with indomethacin, this manipulation reduced medullary blood flow by 50 +/- 4% (N = 16, P < 0.01 vs. obstruction alone), with cortical and total renal blood flow declining by 18 +/- 4% and 16 +/- 2%, respectively (P < 0.01). Unilateral obstruction alone for 24 hours in intact rats resulted in injury (hemorrhage and necrosis) to the papilla and fornix (formed laterally by inner stripe and medially by the inner medulla). These changes were detected as early as 30 minutes after ureteral ligature by staining for fragmented nuclear DNA (TUNEL). Mild damage of thick ascending limbs (mTALs) was associated with substantial medial fornix injury. Indomethacin markedly increased mTAL injury in obstructed kidneys, but attenuated inner medullary damage, both in the medial border of the urinary space and at the papilla. This latter protective effect, probably mediated by the decrease in intrapelvic pressure, was blunted by concomitant intravenous fluid load. Contrast media (iothalamate) and L-NAME (N omega nitro-L-arginine methyl ester) both augmented inner stripe and inner medullary damage in hydronephrotic kidneys. In rats concomitantly subjected to radiocontrast, indomethacin and L-NAME (an acute renal failure protocol, J Clin Invest 94:1069, 1994), unilateral obstruction augmented inner stripe hypoxic damage (65 +/- 6% vs. 24 +/- 11% of mTALs in contralateral kidneys, N = 7, P < 0.01). Injury was maximal at the fornix (93 +/- 6% vs. 39 +/- 14% of mTALs in the mid-inner stripe, P < 0.01) and extended to the outer stripe and medullary rays. Thus, in the rat acute ureteral obstruction alters medullary blood flow and within 24 hours produces medullary damage in both forniceal and inner medullary locations, that is exacerbated by concomitant measures which limit medullary oxygenation. Contrast studies, forced hydration and NSAIDs for renal colic are potentially harmful and their use should be re-evaluated.

Acute Disease↗
PubMed1997

Expression of SSEA-1 (Lewis(x)) on transitional cell carcinoma of the bladder.

The expression of stage-specific embryonic antigen 1 (SSEA-1) in transitional cell carcinomas of the bladder (TCCB) has been reported to correlate with tumor grade and the likelihood of lymphatic metastases. We examined the expression of this antigen in TCCBs to evaluate if staining correlated with grade, stage, recurrence, progression and response to intravesical chemotherapy. We studied the expression of SSEA-1 in TCCBs from 74 patients by staining with two different monoclonal antibodies (Mabs), P-12 and anti-SSEA-1, to evaluate if staining correlated with grade, stage and tumor recurrence. Staining was considered as positive or negative irrespective of the intensity of staining. Extent of tumor staining was measured in quartiles of 100% (25, 50, 75 and 100). Follow-up was available in 47/74 (63%) patients and ranged from 6 months to 13 years (median 2 years). Staining with one or both Mabs was observed in 57/75 (76%) tumors. None of the grade I tumors showed > 50% staining while 26% of grade II and only 33% of grade III tumors showed staining of > 50% of cells. 21% of patients whose tumors showed staining with both Mabs were free of recurrence after resection of the primary tumor; 41% of patients with tumors staining negative with both Mabs showed no recurrence. Expression of SSEA-1 does correlate with tumor recurrence especially in grade II tumors, but the correlation is not very strong (0.05 < p < 0.1). Expression of this antigen is a weak indicator of recurrence in superficial TCCBs.

Aged↗
PubMed1996

Word recall versus reading speed: evidence of preserved priming in head-injured patients.

This study addressed a number of issues. One purpose was to test whether memory-impaired, head-injured patients show the same pattern of memory task dissociation as reported in amnesics, that is, impaired explicit and intact implicit memory performance. The second purpose of this study was to apply the distinction between the acquisition and retention aspects of memory, which has not, as yet, been investigated adequately in the study of implicit memory. The third purpose was to evaluate the contribution of intra-item and inter-item processes in implicit memory. A group of 18 head-injured (HI) patients and 18 control subjects participated in this study. Subjects read two lists of 15 words seven times: five times consecutively, once after 20 min, and after a 1-hr delay. One list was read in the same order and the other in a different order. Acquisition and retention of the information were measured explicitly (i.e., recall of words) and implicitly (i.e., priming-reading speed). The results indicated that novel information is preserved in HI as in other amnesic patient groups, only when implicit, rather than explicit, measures of memory are used. The effect of contextual manipulation (i.e., order of presentation) was interpreted to suggest similar involvement of intra-as well as inter-memory processes in implicit memory in normal and memory-impaired subjects.

Adult↗
PubMed1996

Doppler velocimetry of intraplacental fetal vessels in the second trimester: improving the prediction of pregnancy complications in high-risk patients.

The purpose of our study was to assess the value of fetal intraplacental velocimetry in predicting adverse pregnancy outcome in high-risk patients. Thirty-two women with pregnancies of 22 to 25 weeks' gestation were evaluated. They had demonstrated abnormal first-trimester Doppler characteristics, yet had normal second-trimester umbilical artery velocimetry. Doppler waveforms were obtained and the ratio between intraplacental and umbilical artery resistance indices was calculated. Abnormally high ratios of intraplacental to umbilical artery resistance indices were associated with a significantly higher incidence of pregnancy complications. Among women with abnormal ratios, 17 (80%) of 21 pregnancies had later complications, whereas among those with normal ratios, only two (18%) of 11 women experienced later complications. This study demonstrates that analysis of the ratio between intraplacental and umbilical artery resistance indices in the second trimester improves the diagnostic value of Doppler velocimetry in pregnancies at risk for later obstetric complications.

Blood Flow Velocity↗
PubMed1996

AIDS-associated non-Hodgkin's lymphomas as primary and secondary AIDS diagnoses in hemophiliacs. Hemophilia Malignancy Study Group.

We studied the characteristics and temporal trends of AIDS- associated non-Hodgkin's lymphoma (AIDS-NHL) in individuals with hemophilia. Prospective data were collected on 33 HIV-positive hemophiliacs with AIDS-NHL enrolled in the Hemophilia Malignancy Study (HMS), of whom 21 had primary and 12 had secondary or subsequent AIDS-defining illnesses, and analyzed for frequency and temporal trends. As compared with primary AIDS- NHL, secondary AIDS-NHL occurred at an older mean age, 37 versus 29 years (p = 0.12); at a lower mean CD4 count, 46 versus 154 (p = 0.07); after a longer period of immunosuppression (CD4 < 200/microl), 41 versus 16 months (p = 0.03); and with shorter median survival, 2 versus 7 months (p = 0.09). The presence of EBV in tumor tissue was associated with shorter survival, 1 versus 7 months (p = 0.17). Between 1981 and 1988 and 1989 and 1994, the proportion of primary AIDS diagnoses that were AIDS-NHL changed minimally, 4.6 versus 6.1%, whereas there were significant decreases in Pneumocystis carinii pneumonia (PCP, p = 0.02) and wasting (p = 0.07), and an increase in Candida (p = 0.004). These findings confirm that an increasing proportion of AIDS-NHL in hemophiliacs are occurring as secondary or later AIDS diagnoses, and they are associated with prolonged duration of immunosuppression.

AIDS-Related Opportunistic Infections↗
PubMed1996

Tobacco promotion and susceptibility to tobacco use among adolescents aged 12 through 17 years in a nationally representative sample.

OBJECTIVES: The purpose of this study was to examine whether youth participation in tobacco promotion campaigns is associated with susceptibility to tobacco use. METHODS: Data were collected from telephone interviews of a national random sample of 1047 adolescents 12 to 17 years of age. RESULTS: A proportional odds model was used to estimate the effects of age, gender, presence of a tobacco user in the household, awareness of tobacco promotions, knowledge of a young adult or adolescent friend owning a promotional item, participation in tobacco promotions, and receipt of free tobacco samples or direct mail from tobacco companies on susceptibility to tobacco use. All of the covariates, except for receiving direct mailings and knowing a young adult friend who owned a promotional item, were significantly associated with susceptibility. CONCLUSIONS: There is a strong association between an awareness of and involvement with tobacco promotions and being susceptible to tobacco use or a user of tobacco products.

Adolescent↗
PubMed1996

Multigate spectral Doppler velocimetry for fast assessment of intraplacental fetal circulation: a preliminary study.

The aim of this preliminary study was to investigate the assessment of the intraplacental fetal circulation with a new multigate Doppler system. Doppler velocimetry of the umbilical artery is widely used for assessment of fetal well-being, but its sensitivity is too low for prediction and early detection of pathologic placental processes. Intraplacental velocimetry is more accurate and detects pathologic conditions of the placenta earlier. Color Doppler imaging of intraplacental circulations is a difficult process, and the multigate system was developed to enhance the assessment of intraplacental circulation. This study shows that the multigate system is accurate and is a successful means of fast evaluation of the intraplacental circulation.

Female↗