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Biomedical subjects

S F Cramer

Publications and source records attributed to S F Cramer.

At least 37 records · Page 2Linked to original sources
PubMed1995

Septic pulmonary thrombosis in streptococcal toxic shock syndrome.

A 60-year-old woman who was previously in good health presented with a sore throat, fever, and a flu-like syndrome. Treated initially with acetaminophen and fluids for a presumed viral infection, she had a syncopal episode 4 days later, was admitted to the hospital, and died 3 hours after admission. Laboratory test results suggested sepsis with disseminated intravascular coagulation (DIC), whereas blood cultures grew group A beta-hemolytic streptococci. A postmortem diagnosis of streptococcal toxic shock syndrome was established. It was of particular interest that the pulmonary microcirculation was filled with thrombi that contained numerous gram-positive cocci. Although death from sepsis with DIC is not uncommon, septic pulmonary thrombosis has not been previously described. We speculate that this paradox may reflect unique properties of the virulent strains of Streptococcus pyogenes that are associated with streptococcal toxic shock syndrome.

Female↗
PubMed1995

Epidemiology of uterine leiomyomas. With an etiologic hypothesis.

OBJECTIVE: The few previous epidemiologic studies of uterine myomas have relied on clinical evaluation to select controls, but we previously showed that myomas may be present in more than 75% of such uteri. STUDY DESIGN: We therefore attempted to evaluate risk factors using age-matched controls whose uteri were serially sectioned to exclude the presence of myomas. RESULTS: The small study size precluded a meaningful evaluation of most parameters but tended to confirm the negative association of myomas with cigarette smoking (P = .07). CONCLUSION: Using monoclonal smooth muscle proliferation in human atherosclerotic plaques as a model, we suggest that excessive injury to and repair of the endometrial lining of the uterus may promote monoclonal expansion of smooth muscle cell populations in the uterine wall (i.e., myomas). This theory is largely compatible with the estrogen hypothesis, but fundamental principles of tumorigenesis and previous epidemiologic data on myomas suggest that nutritional factors should be scrutinized as possible initiators (DNA-damaging substances) in the pathogenesis of uterine myomas.

Adult↗
PubMed1995

Myometrial hyperplasia: proposed criteria for a discrete morphological entity.

Myometrial hyperplasia is not a well-established morphological entity. Technical obstacles regarding uterine weight, myometrial cellularity, and myometrial cell orientation have made it difficult to establish objective criteria for diagnosis. In this study, 15 slides that had been interpreted as within normal limits on routine examination were reevaluated because there were areas of myometrium that stood out as relatively blue on scanning magnification of H&E-stained sections. Morphometrically, they all had increased myometrial cellularity, compared with normal myometrium elsewhere on the same slide (P < 0.05), and an increased nucleus/cell ratio (P < 0.001). They occurred in three patterns. The diffuse inframucosal form and the subserosal plaque-like form sometimes corresponded to grossly detectable inframucosal bulges or subserosal ridges. There was also an occult, microscopic intramural pattern of myometrial hyperplasia, which differed from seedling leiomyomas by its lack of nodularity and compression of adjacent myometrium. We propose that these criteria may permit an objective diagnosis of myometrial hyperplasia. We believe that it will be of interest to explore the clinical significance, cell biology, and pathogenesis of this distinctive variation in myometrial structure.

Adult↗
PubMed1992

The nonrandom regional distribution of uterine leiomyomas: a clue to histogenesis?

Although uterine leiomyomas are a major public health problem, very little is known about their etiology or histogenesis. To seek clues as to why the myometrium so frequently gives rise to these tumors, we attempted to determine if the regional distribution of leiomyomas was uniform. It appears that the proportion of leiomyomas in the premenopausal (0.8%) and postmenopausal (3.7%) cervix may be substantially less than the proportion of smooth muscle in the premenopausal (7.3%) and postmenopausal (17%) cervix. These data suggest that the smooth muscle cells of the corpus uteri may be at higher risk for neoplastic transformation than those of the cervix. Within the corpus there appeared to be a relative excess of fundic leiomyomas (premenopausal, 89%; postmenopausal, 86%) as compared with fundic smooth muscle (premenopausal, 79%; postmenopausal, 61%). No such excess was apparent in the isthmus or cornu. Immunohistochemical studies of estrogen and progesterone receptors in premenopausal and postmenopausal myometrium were uniformly positive, with no regional differences to suggest a hormonal basis for regional susceptibility to leiomyomas. It may be fruitful to search for precursor lesions and other factors predisposing to neoplastic development in fundic myometrium.

Female↗
PubMed1991

The mystique of the mistake. With proposed standards for validating proficiency tests in anatomic pathology.

Variability in classification in anatomic pathology does not necessarily indicate that a mistake has been made. It is usually an artifact, created when pathologists choose a single category from among two or more justifiable alternatives. This is most common when standard classifications with uniform terminology are not used. It also can occur when classification systems are not constructed so as to insure mutual exclusivity of categories. It is proposed that a proficiency test in anatomic pathology should not be considered scientifically valid until a professional organization primarily concerned with anatomic pathology has endorsed its proposed classification system as having categories that are close to 100% mutually exclusive in the hands of expert pathologists not involved in developing the system. All possible precautions should be taken to insure that the "right answers" for any proficiency test are generated in a way that excludes the possibility of multiple justifiable alternatives.

Clinical Competence↗
PubMed1991

The origin of epidermal melanocytes. Implications for the histogenesis of nevi and melanomas.

Among the most venerable concepts in dermatopathology is Unna's 19th century notion of Abtropfung, ie, that melanocytes drop off from the epidermis to the dermis during the histogenesis of melanocytic tumors. Paradoxically, however, Unna's basic premise of an epidermal origin for melanocytes has been seriously questioned for over 40 years, based on experimental evidence favoring a neural crest origin for melanocytes. Recent work has strengthened the evidence for a neural crest origin of epidermal melanocytes, and it has been suggested that the concept of Abtropfung be replaced by the concept of Hochsteigerung. The concept of Hochsteigerung holds that melanocytes migrate up from the dermis into the epidermis-not only in normal development, but also during normal tissue maintenance. It now seems likely that the precursor of melanocytes, in both normal and abnormal differentiation, may not be a melanoblast (a primitive cell committed to melanocytic differentiation) but rather a pluripotential cell. Although axon-investing Schwann cells have been the traditional focus as the closest relative of the epidermal melanocyte, recent studies suggest that another nerve sheath cell, the perineural cell, might be a better candidate. These concepts have profound implications for the histogenesis of melanocytic nevi and melanomas.

Animals↗
PubMed1990

The frequency of uterine leiomyomas.

As a leading cause of hysterectomy in premenopausal women. uterine leiomyomas are a major public health problem. However, very little work has been done on their epidemiology. Indeed, their true frequency has never been established using systematic and meticulous methods. In this study, gross serial sectioning at 2-mm intervals was applied as an adjunct to routine pathology processing in 100 consecutive total hysterectomy specimens. This tripled the number of leiomyomas noted in routine pathology reports. There were 649 leiomyomas in 77 of 100 uteri, with multiplicity of leiomyomas in 84%. Although leiomyomas were more numerous and larger in women with a clinical diagnosis of myomatous uterus, the incidence was no higher than in uteri removed for other reasons. The postmenopausal incidence of leiomyomas was no lower than the premenopausal incidence, although postmenopausal leiomyomas were smaller and fewer. These findings suggest that epidemiologic studies of leiomyomas may not be valid if they are based only on clinical diagnoses or routine pathology reports.

Adult↗