Glial reactions and degeneration of myelinated processes in spinal cord gray matter in chronic experimental autoimmune encephalomyelitis.

Multiple sclerosis and experimental autoimmune encephalomyelitis (EAE) result in inflammatory white matter lesions in the CNS. However, information is sparse with regard to the effects of autoimmune demyelinating disease on gray matter regions. Therefore, we studied the late effects of chronic EAE in C57BL/6 mice on the spinal cord gray matter using immunohistochemistry. Here, EAE induced marked astrocytic, microglial, and macrophage activation in the ventral horn gray matter, without any motoneuron loss. Activated caspase-3 was also increased in the ventral horn gray matter. Furthermore, activated poly (ADP-ribose) polymerase (PARP), another apoptotic marker, co-localized with myelin basic protein (MBP) of oligodendrocyte processes, but not with the oligodendroglial cell body marker, adenomatous polyposis coli gene clone CC1 (APC-CC1), or with neurofilament marker (RT-97) or synaptophysin of axonal arbors. However, there was no associated increase in the number of terminal deoxynucleotidyl transferase (TdT) mediated-dUTP nick end labeling positive nuclei in the spinal cord gray matter of EAE mice. In addition, co-localization of MBP and the low-affinity neurotrophin receptor, p75, was demonstrated, further supporting the notion of apoptotic oligodendrocyte process degeneration in the gray matter of EAE mice.

Differential regulation and transcriptional control of immediate early gene expression in forskolin-treated WEHI7.2 thymoma cells.

Agents that increase intracellular cAMP are frequently growth inhibitory for lymphocytes and induce apoptosis in cortical thymocytes by regulating gene expression. In the present study, immediate early gene expression was examined in WEHI7.2 thymoma cells undergoing cAMP-mediated apoptosis. Temporal differences in c-fos, junB, and inducible cAMP early repressor (ICER) steady-state mRNA levels were observed after forskolin exposure. Maximal induction of c-fos and junB occurred within 1 h, returning to basal levels by 3.5 h. In contrast, a 1.5-h time lag was observed before ICER transcript levels increased, reaching maximal levels after 3.5 h. This rise in expression, correlating with the decrease in c-fos and junB levels, preceded apoptotic DNA fragmentation by 1.5 h. Transient expression of ICER promoter constructs demonstrated that cAMP responsiveness occurred through cAMP-autoregulatory response element (CARE)3/4, two of the four proposed response elements in the ICER promoter. In contrast to the cAMP-responsive cell line JEG-3, CARE1/2 was not functional for cAMP-activated transcription in WEHI7.2 cells. An observed differential binding pattern of WEHI and JEG nuclear extracts to these elements may account for the cell-specific differences in expression patterns. To determine the role of endogenous ICER in regulating gene expression, cells were treated with two sequential doses of forskolin after which ICER and c-fos mRNA levels were measured. The high levels of cAMP-induced ICER expression dramatically reduced a second induction of c-fos. These data suggest that ICER expression may function as an antioncogene to attenuate the expression of certain protooncogenes, thereby preventing transformation and oncogenesis due to continuous overexpression. Moreover, inhibition of growth-stimulatory genes may be required for the activation of the cell death machinery in specific cells.

Functional analysis of the mouse ICER (Inducible cAMP Early Repressor) promoter: evidence for a protein that blocks calcium responsiveness of the CAREs (cAMP autoregulatory elements).

Although Ca2+ and cAMP mediate their effects through distinct pathways, both signals converge upon the phosphorylation of the cAMP response element (CRE) binding protein, CREB, thereby activating transcription of CRE-regulated genes. In WEHI7.2 thymocytes, cAMP increases the expression of the inducible cAMP early repressor (ICER) gene through CRE-like elements, known as cAMP autoregulatory elements (CAREs). Because Ca2+ -and cAMP-mediated transcription converge in WEHI7.2 thymocytes, we examined the effect of Ca2+ fluxes on the expression of the ICER gene in these cells. Despite the presence of multiple CAREs within its promoter, ICER gene transcription was not activated by Ca2+. Moreover, Ca2+ attenuated the stimulatory effect of cAMP on ICER expression. Transient expression of reporter constructs demonstrated that when these CAREs were placed in a different DNA promoter context, the elements became responsive to Ca2+. Detailed studies using chimeric promoter constructs to map the region responsible for blocking the transcriptional response to Ca2+ indicated that a small portion of the ICER promoter was necessary for the effect. Southwestern blot analysis identified a 83-kDa nuclear protein that bound specifically to that region. The relative binding activity of the factor to the ICER promoter and mutant promoter sequences correlated with an inhibition of Ca2+ -activated gene expression in WEHI7.2 cells. These data suggest that the factor functions as a putative Ca2+ -activated repressor of CREB/CRE-mediated transcription. Thus, depending on the surrounding context in which the CRE is located, CREs of individual genes can be regulated separately by Ca2+ and cAMP despite the convergence of these two signaling pathways.

Diabetic ketoacidosis associated with cocaine use.

BACKGROUND: Multiple risk factors for diabetic ketoacidosis (DKA) have been described, including omission of insulin therapy and clinical conditions known to increase counterregulatory hormones. Recently, substance abuse has been identified in patients with DKA. We observed many cases of DKA in cocaine users, although the association between cocaine use and DKA has not been well described in the medical literature. METHODS: We performed a retrospective case-control study of admissions for DKA in cocaine users and non-user controls in an urban teaching hospital from January 1, 1985, to December 31, 1994. RESULTS: We identified 720 adult admissions for DKA. Twenty-seven cocaine users accounted for 102 admissions (14% of all DKA admissions). The users were compared with 85 nonuser controls who had 154 DKA admissions. Cocaine users had more admissions for DKA (mean, 3.78 vs 1.81; P = .03). Cocaine users were less likely than controls to have an intercurrent illness identified as a precipitating factor for DKA (14.7% vs 33.1%; P<.001) and were more likely to have missed taking insulin prior to admission (45.1% vs 24.7%; P<.001). Although cocaine users had higher serum glucose levels on admission (32.9 mmol/L [593.4 mg/dL] vs 29.5 mmol/L [531.1 mg/dL]; P =.03), no differences in intensity of illness or treatment outcome were detected. CONCLUSIONS: In this preliminary study, cocaine use was found in a significant number of adults admitted with DKA and was associated with more frequent omission of insulin therapy and the absence of precipitating systemic illness. Either because of its association with insulin therapy omission or its effects on counterregulatory hormones, cocaine use should be considered a risk factor for DKA, particularly in patients with multiple admissions.

Screening and early diagnosis of gynecologic cancers.

Gynecologic malignancies remain an important health concern for women. The primary care practitioner plays a valuable role in performing regular Pap smears and pelvic examinations. Although routine screening for asymptomatic women for ovarian and endometrial cancer cannot be recommended at this time, vaginal ultrasound is a valuable tool for the evaluation of postmenopausal bleeding and ovarian masses.

Pharmacotherapy for opioid and cocaine abuse.

The need for continued development of medications to address opioid and cocaine addiction is unequivocal. Methadone maintenance, despite its limitations, remains the best-established pharmacologic treatment for opioid dependence. Continued participation in methadone programs is associated with decreased risk of acquiring HIV infection. Clonidine alone or combined with naltrexone may be used for opioid detoxification in the office practice. At the present time, no proven pharmacologic therapy for cocaine addiction exists.

Case report: toxic shock syndrome arising from cellulitis.

Toxic shock syndrome is a febrile, multiorgan illness related to toxins elaborated by staphylococcal or streptococcal infections. In the 1980s, most cases were associated with menstruation. More recently, many cases now are unrelated to menses. In this article, the authors describe a case of a nonmenstruating woman with toxic shock syndrome, associated with cellulitis of her arm. Cultures of the arm grew Staphylococcal aureus, which produced enterotoxin B.

Pneumatosis cystoides intestinalis in progressive systemic sclerosis: a case report and literature review.

Pneumatosis cystoides intestinalis (PCI) is an uncommon disease manifestation characterized by the presence of air in the bowel wall. It is a benign condition that often responds to conservative management; however, it may be a harbinger of end stage disease, particularly in progressive systemic sclerosis. The authors report a case of pneumatosis cystoides intestinalis in a patient with progressive systemic sclerosis in the setting of mixed connective tissue disease that responded to conservative treatment. They review the current literature on pneumatosis cystoides intestinalis, focusing on possible etiologies and potential therapies.

Breast cancer screening.

Breast cancer, as the second leading form of cancer death among women, causes significant morbidity and mortality. The primary care physician can help raise the survival rate of women with breast cancer by providing important screening procedures that will lead to early diagnosis and treatment. Screening mammography and regular breast physical examinations are the current screening procedures of choice. Although there is still considerable debate over the age and interval at which women should undergo screening (see Table 1 for recommendations from various organizations), the primary care physician's recommendation is the single most important factor and will certainly lead to a higher screening rate for women in the greater at-risk age groups. Judicious use of these screening procedures should allow primary care physicians to catch more breast cancers at an early, curable stage.

Is your patient using cocaine? Clinical signs that should raise suspicion.

Cocaine use often has profound effects on the body. Medical complications that may be seen in users include headache, sexual dysfunction, violent behavior, chronic cough, seizures, and myocardial infarction. The type of cocaine used and the method of use often determine the kind of problems that occur. Patients may be reluctant or unable to offer information about their drug use during evaluation, so awareness of the medical consequences of cocaine use and a high index of suspicion are essential.

Cocaine abuse.

PURPOSE: To discuss the forms of cocaine that are available and their methods of administration and to review the medical complications of cocaine abuse. DATA SOURCES: Pertinent articles were identified through a MEDLINE search of the English-language literature from 1986 to 1992 and through a manual search of bibliographies of all identified articles. STUDY SELECTION: All articles describing complications of cocaine use were either case reports, review articles, or small series. No controlled studies on the subject were available. DATA SYNTHESIS: A qualitative description of reported complications without the use of quantitative methods. RESULTS: Multiple complications of cocaine use have been described and are often related to the method of administration of cocaine. Since the introduction of freebase and "crack" cocaine, new complications have been noted, and nearly all organ systems have been affected. Indirect complications, related to violent behavior and infectious diseases, are also important consequences of cocaine use. CONCLUSIONS: Adverse reactions to cocaine use should be considered in the differential diagnosis of various disorders, particularly ischemic events in young adults. The actual frequency of each complication is unknown.

Pharmacologic studies on the differential influence of inhibitors of neutral endopeptidase on nonadrenergic, noncholinergic contractile responses of the guinea pig isolated hilar bronchus to transmural electrical stimulation and exogenously applied tachykinins.

Nonadrenergic, noncholinergic contractile responses of guinea pig hilar bronchi to transmural electrical stimulation (TES) have been suggested to be due to release of endogenous tachykinins from capsaicin-sensitive neurons (C-fibers). Thiorphan and phosphoramidon, inhibitors of neutral endopeptidase (NEP, the major enzyme responsible for degrading tachykinins), were found to potentiate contractile responses of this isolated airway segment to TES and exogenously applied capsaicin, substance P and neurokinin A. However, the magnitude of potentiation by either inhibitor was smaller for TES and capsaicin (less than 10-fold leftward shift) than for the substrate agonists (about 100-fold leftward shift). This quantitative difference in potentiation by NEP inhibitors does not appear to be due to an influence of vasoactive intestinal peptide or calcitonin gene-related peptide, two endogenous peptides that might be released concomitantly by TES. Neither peptide caused marked effects on contractile responses to TES or tachykinins when applied to the isolated tissues. Addition of inhibitors of serine proteases, aminopeptidases, acetylcholinesterase and angiotensin-converting enzyme failed to further potentiate responses to TES in the presence of thiorphan. Therefore, the contractile response does not appear to be further modified by the activity of these peptidases. Neuropeptide gamma, but not neuropeptide K, was potentiated by thiorphan. The data suggest that peptides that are not substrates for NEP (for example, neuropeptide K) may also be released by TES from capsaicin-sensitive neurons to cause contraction. This may, at least in part, explain the quantitative difference in potentiation by NEP inhibitors of contractile responses to TES and to exogenously applied NEP-sensitive tachykinins in the guinea pig hilar bronchus.

Involvement of thyrotroph embryonic factor in calcium-mediated regulation of gene expression.

In the present study, we used an expression cloning strategy to identify transcription factors that bind specifically to a limited region of the inducible cAMP early repressor (ICER) promoter and regulate transcription. Murine thyrotroph embryonic factor (mTEF) was isolated and was shown to bind to a site located at nucleotides -117 to -108 from the transcriptional start site. Transient expression of reporter constructs containing either a consensus TEFRE or the icerTEF binding site demonstrated that TEF-dependent transcription correlated with relative binding affinities, i.e. the consensus TEFRE bound TEF more tightly and was more responsive to TEF than the icerTEFRE. Because the icerTEFRE overlapped a cAMP response element, the responsiveness of these sequences to either cAMP or Ca(2+) was tested. Although TEF expression had no effect on the cAMP-regulated transcriptional response of the ICER promoter, TEF did confer calcium responsiveness to these sequences. Calcium also modestly increased the TEF-mediated transcription from a consensus TEFRE. Additional studies using Ca(2+)-activated kinases indicate that Ca(2+)/TEF/TEFRE-regulated transcription may be mediated through Ca(2+)/calmodulin-dependent kinase (CaMK) IV. Moreover, studies with the icerTEFRE in a CaMK IV-deficient cell line demonstrated that these cells were transcriptionally unresponsive to thapsigargin; however, responsiveness was restored by co-expression of the active CaMK IV. These studies are the first to demonstrate that TEF is a calcium-responsive transcription factor, and they suggest that there are two classes of TEF-regulated genes. One class, represented by a consensus TEFRE, is regulated by TEF in the resting cell; the second class, represented by icerTEFRE, is regulated by TEF in the calcium-activated cell.

Evidence of gender bias in patients undergoing flexible sigmoidoscopy.

Some studies have revealed gender bias against women in various aspects of medical care. There is no substantial evidence of gender bias in patients undergoing cancer evaluations, specifically colorectal cancer screening and diagnosis of colorectal complaints. This study was designed to examine the role of gender bias related to patients undergoing flexible sigmoidoscopy. At the University of South Florida, we conducted a retrospective study of 1910 patients at three distinct flexible sigmoidoscopy clinics over several years, through 1992. The proportions of male and female patients who underwent the procedure for indications of either screening for colorectal cancer or the diagnosis of colorectal complaints were determined. These proportions were compared with the respective male and female patient proportion from the total number of currently active patients at each site who were eligible to have the procedure for an appropriate indication. At all three sites, a significantly smaller proportion of women (p < 0.01) underwent the procedure than expected. This was true for both screening and diagnostic indications. Conversely, at all sites significantly more men (p < 0.01) underwent the procedure for both indications. The results of this study suggest gender bias against women for patients undergoing flexible sigmoidoscopy for both screening and diagnosis. This bias may adversely affect the lethality of colorectal cancer in women. It is important to determine if such biases are influenced by the physician's recommendation or mainly due to patient attitudes.