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J McClellan

Publications and source records attributed to J McClellan.

30 records · Page 2Linked to original sources

Regulation of scatter factor production via a soluble inducing factor.

Scatter factor (SF) (also known as hepatocyte growth factor [HGF]) is a fibroblast-derived cytokine that stimulates motility, proliferation, and morphogenesis of epithelia. SF may play major roles in development, repair, and carcinogenesis. However, the physiologic signals that regulate its production are not well delineated. We found that various human tumor cell lines that do not produce SF secrete factors that stimulate SF production by fibroblasts, suggesting a paracrine mechanism for regulation of SF production. Conditioned medium from these cell lines contained two distinct scatter factor-inducing factor SF-IF activities: a high molecular weight (> 30 kD), heat sensitive activity and a low molecular weight (< 30 kD) heat stable activity. Further studies revealed that SF-producing fibroblasts also secrete factors that stimulate their own SF production. We characterized the < 30-kD SF-IF activity from ras-3T3 (clone D4), a mouse cell line that overproduces both SF and SF-IF. The < 30-kD filtrate from ras-3T3 conditioned medium induced four- to sixfold increases in expression of SF biologic activity, immunoreactive protein, and mRNA by multiple SF-producing fibroblast lines. Ras-3T3 SF-IF activity was stable to boiling, extremes of pH, and reductive alkylation, but was destroyed by proteases. We purified ras-3T3 SF-IF about 10,000-fold from serum-free conditioned medium by a combination of ultrafiltration, cation exchange chromatography, and reverse phase chromatography. The purified protein exhibited electrophoretic mobility of about 12 kD (reduced) and 14 kD (nonreduced) by SDS-PAGE. The identity of the protein was verified by elution of biologic activity from gel slices. Purified SF-IF stimulated SF production in a physiologic concentration range (about 20-400 pM). Its properties and activities were distinct from those of IL-1 and TNF, two known inducers of SF production. We suggest that SF-IF is a physiologic regulator of SF production.

3T3 Cells↗

Practice parameters for the assessment and treatment of children and adolescents with schizophrenia. American Academy of Child and Adolescent Psychiatry.

These practice parameters review the literature on children and adolescents with schizophrenia. Because this literature is sparse, information is also drawn from research with adults. Clinical features in youth with schizophrenia include predominance in males, high rate of premorbid abnormalities, increased family history of schizophrenia, and often poor outcome. Diagnostic issues include the overlap, and therefore potential for misdiagnosis, between the first presenting symptoms of schizophrenia and those of psychotic mood disorders, developmental disorders, organic conditions, and other nonpsychotic emotional/behavioral disorders. Treatment should include using antipsychotic medications in conjunction with psychoeducational, psychotherapeutic, and social and educational support programs.

Adolescent↗

Peer review.

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Dentistry↗

Familial pancreatic cancer (Part II): Surveillance, diagnostic tests, and surgical strategies.

We have provided a description of the current state of knowledge relevant to familial/hereditary pancreatic cancer. Since the most important clinical ramifications of this disease, whose incidence and mortality are essentially the same, rests upon its earlier detection, we have also characterized available diagnostic tests, surgical strategies, and current knowledge about its pathology. We believe that advances in control of pancreatic cancer will be heavily impacted by progress in the search for new and better diagnostic tests. These could include monoclonal antibodies targeted to pancreatic tumor tissue, and possibly pancreatic site-specific P450's, as well as biomolecular/genetic techniques, particularly when focused on individuals at high risk. Thus, family studies are important in this disease because if an autosomal dominantly inherited form of pancreatic cancer is delineated, one could identify individuals at high risk early in life. Comparison could then be made with individuals in branches of the family where the disease is not segregating. Thus, there would be a greater potential for discovery of methods for early detection with evaluation of sensitivity and specificity in families wherein the predictability for pancreatic cancer occurrence is high.

Adenoma↗

Familial pancreatic cancer: clinicopathologic study of 18 nuclear families.

Host factors have been given scant attention in the search for etiology in pancreatic cancer. Several anecdotal reports have identified its familial clustering, whereas a recent population-based case/control study has shown that 6.7% of cases and 0.7% of controls had positive family histories of this disease (p less than 0.001). Forty-seven individuals with pancreatic cancer from 18 families were identified from a review of the medical records of all kindreds on file at our Hereditary Cancer Institute. The observed sex ratio, age of onset, histologic type, and survival were comparable to published data on unselected patients. We did not identify any pattern of extra-pancreatic cancer association. A serious limitation of our study is its lack of a population-based case/control design. Whereas our data are primarily descriptive, they do indicate the need to learn more about the role of familial factors in the etiology of pancreatic cancer. Pancreatic cancer is increasing in incidence, and its prognosis is almost uniformly dismal; identification of persons at high risk may improve cancer control.

Aged↗

Prevention of psychiatric disorders in children.

Mental health professionals have the capability to identify children who are at risk of developing psychiatric disorders. Early intervention with these children can help prevent significant maladjustment and reduce their future need for mental health services. The authors review studies of environmental and temperamental factors associated with children's vulnerability and resilience to psychiatric disorders. The goals and effects of selected prevention approaches designed for preschool children, elementary-school-age children, and parents are discussed. Families in need of prevention services may be more likely to use these interventions if they are integrated into existing school programs and social welfare systems.

Child↗

Response to lactate infusion in generalized anxiety disorder.

Intravenous sodium lactate infusion provokes symptoms of panic in patients with panic disorder at a significantly higher rate than in normal controls. Lactate sensitivity has been postulated to be specific for patients with panic attacks regardless of frequency of attacks or coexisting diagnoses. The authors present results of a pilot study of lactate infusions in patients with generalized anxiety disorder (GAD) without any history of panic attacks. Patients with GAD reacted more like panic disorder patients than like normal controls in anxiety and symptom scores during lactate infusion and in the rate of positive responses to lactate. Although preliminary, these findings raise questions regarding the specificity of lactate sensitivity and the relationship of GAD to panic disorder.

Adult↗

Initial alkylating agent chemotherapy in a leukemic hairy cell patient.

A patient with moderate splenomegaly and the leukemic phase of hairy cell leukemia presented with a white blood cell count (WBC) of 85,600/mm3 with 87% hairy cells and platelets of 125,000/mm3. Initial therapy consisted of chlorambucil alone at 4 mg each day. Within 6 months, the WBC decreased to 27,000/mm3 with 82% hairy cells, and the spleen was not palpable; platelets remained at 142,000/mm3. The patient has continued to do well for 2 years since the start of therapy, requiring no transfusions and having no problems secondary to organ infiltration. Selected hairy cell patients, those with a significant leukemic phase and with only mild thrombocytopenia, may benefit from initial chlorambucil therapy rather than immediate splenectomy.

Chlorambucil↗

Two-dimensional echocardiographic assessment of vegetative endocarditis.

Real-time, two-dimensional echocardiography was used to document the presence and assess the size and location of vegetative lesions of the cardiac valves and chambers in seven patients with bacterial endocarditis. Anatomic correlation (surgical or autopsy) was accurate in all patients. Two-dimensional echocardiography was shown to be of particular value in determining morphologic characteristics of the lesions since this technique provides spatial information concerning moving cardiac structures. The results of two-dimensional echocardiography were most helpful in determining selected aspects of the clinical care provided for each patient. These data demonstrate that real-time, two-dimensional echocardiography, in combination with M-mode imaging techniques, may be of great potential value in the detection of vegetative endocarditis. Furthermore, reliable assessment of lesion size and location may, in time, become a valuable method for following the morphologic changes that occur in vegetative lesions, and thus determine the efficacy of antibiotic therapy. This information may also provide a means for evaluating certain patients for surgical intervention.

Adolescent↗

Children on child protective service caseloads: prevalence and nature of serious emotional disturbance.

A multivariate, criterion-referenced approach was used to assess prevalence of serious emotional disturbance among children on protective service case loads. Of 140 recipients of protective services, 72% were statistically indistinguishable from children in Washington State's most intensive mental health treatment programs. School problems, substance abuse, and antisocial behaviors were common in the sample, as were family histories of mental illness or substance abuse. Greatest service needs included family support groups, outpatient treatment, school-based treatment, and diagnostic services. These results underline the importance of structural changes to facilitate cross-system collaboration between mental health and protective services.

Adolescent↗