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Biomedical subjects

M B Hopkins

Publications and source records attributed to M B Hopkins.

At least 19 recordsLinked to original sources
PubMed2000

Fiber type-specific differential expression of angiogenic factors in response to chronic hindlimb ischemia.

Alterations in endogenous levels of the angiogenic proteins basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) were assessed in rabbit hindlimb muscles subjected to 1, 5, or 21 days of ischemia. In the glycolytic [tibialis anterior (TA)] and the oxidative [soleus (SOL)] muscles from the ischemic and contralateral (control) hindlimb, bFGF and VEGF protein expression was determined by ELISA and immunoblot analysis. Total VEGF protein expression was greater in oxidative than in glycolytic muscles after 5 days of hindlimb ischemia. In SOL muscle, total VEGF detected by ELISA in ischemic limbs was increased to 137, 300, and 220% of control at 1, 5, and 21 days, respectively. However, in TA, total VEGF expression by ELISA was increased only at 1 and 5 days of ischemia to 140 and 134% of control, respectively. By immunoblotting, the expression of the 165-amino acid isoform (VEGF(165)) was initially decreased to 55% of control in ischemic SOL at 1 day but was increased to 250% of control at day 5 and remained at 155% at day 21. In TA, VEGF(165) was increased to 260% of control at 1 day of ischemia but only to 150% of control by day 5. The only significant change in bFGF expression in either the oxidative or glycolytic muscles was a small increase (129% of control) at 21 days in SOL. This study demonstrates that the magnitude and direction of change in VEGF protein expression depend on VEGF subtype, muscle fiber type, and duration of ischemia. These findings suggest that strategies in therapeutic angiogenesis may need to differ depending on muscle fiber type.

Animals↗
PubMed1996

Bronchoalveolar lavage cytology in pulmonary alveolar proteinosis.

Pulmonary alveolar proteinosis (PAP) is an uncommon disease in which alveoli are progressively filled with surfactant-related material. Although a definitive diagnosis is usually made by an open lung biopsy, bronchoalveolar lavage (BAL) cytology may play a decisive role in the clinical work-up of these patients, and, in some cases, may spare a patient a more invasive diagnostic procedure. The authors present three patients in whom BAL cytology specimens contained the characteristic (although not specific) globules of amorphous proteinaceous PAS-positive material accompanied by only rare background macrophages and inflammatory cells. The patients include a 40-year-old man with an 8-year history of fever of unknown origin, a 30-year-old man with a chronic nonproductive cough, and a 6-year-old boy diagnosed at 5 months of age with osteopetrosis and hypogammaglobulinemia who subsequently developed a disseminated Mycobacterium avium-intracellulare infection. All specimens stained with Gomori methenamine silver (3) and Ziehl-Neelsen (2) were negative for microbial organisms, Ultrastructural examination of two specimens revealed the characteristic lamellar structures of surfactant, increasing diagnostic specificity. Lung biopsies and/or autopsy subsequently confirmed the diagnosis in all three cases. The characteristic cytologic and ultrastructural features of PAP in BAL specimens are presented along with the morphologic differential features of other entities which potentially could be confused with PAP.

Adult↗
PubMed1993

Processing forms used in the bone marrow transplantation laboratory: toward standardization.

We developed a set of one-page data forms for each procedure that is used in the different types of bone marrow transplant processing performed in our laboratory. In this paper we duplicate this set of forms and illustrate how they can be "mixed and matched" to accommodate the type of processing that is being carried out on a particular day. Finally, we describe the benefits that we have gained from using this system and suggest interlab advantages to adopting such a system.

Bone Marrow Transplantation↗
PubMed1993

An open-trial evaluation of mitoxantrone in the treatment of progressive MS.

We treated 13 patients with progressive MS with mitoxantrone. All patients received a standard IV dose of mitoxantrone (8 mg/m2) every 3 weeks for a total of seven infusions, with dosage adjustments depending on the hematologic profile at the nadir. The treatment was well tolerated, with the most common side effect being mild nausea. Four of seven women developed transient secondary amenorrhea. The postenrollment clinical behavior of these patients was generally more favorable than during the 18 months prior to enrollment (only three of 13 patients developed an increase in the Expanded Disability Status Scale of more than 0.5 points), suggesting a possible treatment effect, but comparison with two historical control groups (both the active and placebo groups from the Canadian Cooperative Trial of Cyclophosphamide and Plasma Exchange) does not suggest that mitoxantrone was efficacious. Eight of 12 patients had evidence of MRI activity on 13 of 29 follow-up visits. This small, open-labeled pilot study did not provide strong support for proceeding with a randomized, controlled trial of this dosage regimen of mitoxantrone in patients with progressive MS.

Adult↗
PubMed1992

Heparin content of washed red blood cells from the cardiopulmonary bypass circuit.

Reinfusion of red blood cells (RBC) from the extracorporeal circuit following cardiopulmonary bypass (CPB) reduces patient exposure to homologous blood. Because infusing unneutralized heparin might exacerbate postoperative bleeding, this study examines the heparin content of the washed packed RBC produced by a commonly used autotransfusion device. This RBC product was derived from the residual whole blood in the oxygenator circuit after CPB. A wash volume of 750 mL of normal saline produced heparin concentrations below 0.04 USP U/mL. A 500 mL wash volume yielded heparin concentrations ranging from 0.08 to 0.22 USP U/mL, and could be used if time did not permit an additional wash. RBCs produced by the usual complete wash cycle do not contain clinically significant amounts of heparin; thus, they would not require a supplemental protamine dose.

Adult↗
PubMed1991

The effects of hypnosis and of imagery on bleeding time: a brief communication.

2 studies are reported, one using hypnotized Ss selected on hypnotizability and one using Ss selected on imagery vividness, whose purpose is to examine whether non-patient Ss can control their bleeding in a laboratory setting. All Ss were cut on both arms with the "Surgicutt" device, an instrument that automatically makes a cut that will bleed from 2 to 10 minutes. Results suggest that Ss, who are instructed to reduce the bleeding time in one arm and to let the other arm bleed normally, are not able to control bleeding time.

Adult↗
PubMed1991

Hematocrit in relation to Apgar scores in SGA infants.

SGA infants have an increased incidence of low Apgar scores. At the same time they frequently have a high hematocrit. Since both affect outcome, it is important to know if a relationship exists between these two factors. In a study of 139 SGA newborns many had low Apgar scores at one minute: 63% of the preterms and 29% of the fullterms. Frequent abnormal hematological findings included high hematocrit. We found a positive correlation between hematocrit and the Apgar score at one minute of life that was statistically significant. The babies with a high hematocrit had significantly more often good Apgar scores. The correlation was present in preterm babies (r = 0.55) as well as in fullterms (r = 0.32). It is concluded that a high hematocrit probably protects the SGA newborn against acute perinatal asphyxia. It is possible that both low Apgar scores and "normal" hematocrit are signs of a chronically impaired SGA fetus.

Apgar Score↗
PubMed1988

Tenckhoff catheter cytology in patients with ovarian cancer.

In order to expose malignant cells to high concentrations of cytotoxic chemotherapeutic agents, drugs can be instilled directly into the peritoneal cavity of patients with ovarian carcinomas through a Tenckhoff catheter. The peritoneal dialysate removed during such therapy can be examined cytologically for the presence of carcinoma cells. The cytologic specimens from Tenckhoff catheters from 40 consecutive patients with primary ovarian (39) and tubal (1) cancer who received intraperitoneal chemotherapy have been reviewed retrospectively. A total of 237 specimens yielded 78 (33%) positive, 138 (58%) negative, and 21 (9%) inconclusive or suspicious fluids. The major diagnostic problem was the marked mesothelial atypia, which may be related to the high concentrations of cytotoxic agents intimately in contact with the peritoneum. Of the 15 patients who had tissue examined after placement of the catheter (mean interval, 5 months), results agreed with those of the catheter cytologic specimens in ten patients. The catheter cytologic specimen was never positive when histology was negative. Of the 36 patients with evaluable follow-up (mean, 19 months), agreement between the clinical course and the catheter cytologic results was found in 27 patients (75%). Again, interpretation of the catheter specimens was never positive in the face of a benign clinical course. Thus, evaluation of catheter specimens by cytologic examination has a diagnostic sensitivity and specificity of 59% and 100%, respectively. Tenckhoff catheter cytology has proven to be a rather valuable tool to monitor persistent or recurrent intraperitoneal ovarian carcinoma.

Adult↗
PubMed1988

Cervicovaginal psammoma bodies. The initial presentation of the ovarian borderline tumor.

Psammoma bodies associated with cancer cells of ovarian and endometrial origins have been previously described in cervicovaginal smears, as have psammoma bodies from totally benign processes. We describe the presence of numerous psammoma bodies in the cervical smear, endometrial curettage, and peritoneal wash specimens from a patient with subsequently discovered bilateral, ovarian, borderline serous tumors. We morphologically traced the transit of these psammoma bodies and their associated cytologically benign tumor cells through the entire female genital tract.

Fallopian Tubes↗
PubMed1987

Bizarre (pseudomalignant) granulation-tissue reactions following ionizing-radiation exposure. A microscopic, immunohistochemical, and flow-cytometric study.

Two patients developed extremely bizarre (pseudomalignant) granulation-tissue reactions in the larynx and facial sinuses, following radiation therapy for carcinoma. Containing pleomorphic spindle cells and numerous (sometimes atypical) mitotic figures, both tumefactive lesions simulated high grade malignancies. While the pleomorphic cells contained vimentin immunoreactivity, they were nonreactive for low or high molecular weight keratin. Flowcytometric study of paraffin-embedded tissues revealed DNA indexes of 0.75 and 1.0. Neither recurred locally nor spread distantly after therapy. Their granulation-tissue growth pattern, and the presence of stromal and endothelial cells showing similar degrees of cytologic atypia were central to their recognition as benign. These findings show that severely atypical, sometimes aneuploid, granulation-tissue reactions can occur following radiation exposure. Care should be taken not to misinterpret these lesions as malignant.

Aged↗
PubMed1986

Red blood cell antibody identification and confirmation using commercial panels. A computer program for the IBM personal computer.

A menu-driven computer program that utilizes a data base of commercial panels was developed to assist in the identification and confirmation of red blood cell antibodies. A selected panel, along with the corresponding serum reactions, is displayed on the monitor and possible antibody patterns including dosage-dependent patterns are highlighted. A panel interpretation is then printed that includes a list of the possible (nonexcluded) antibodies, a probability level of identification for each possible antibody, and a table of antibody characteristics to aid in the differentiation among the possible antibodies. The panel data base can also be searched for additional red blood cells of specified phenotypes to confirm each suspected antibody. These additional red blood cells may be combined into a temporary panel for computer analysis. The program can also enter, print, edit, and delete any commercial panel from the data base. This computer program has proved to be faster and more accurate than the standard manual method for panel analysis, especially when multiple antibodies are present.

Antibodies↗
PubMed1985

Pathobiologic study of pituitary tumors: report of 62 cases with a review of the recent literature.

Advances in radioimmunoassay procedures, immunocytochemistry, neuroradiologic imaging, and the surgical and medical treatment of pituitary adenomas have led to reappraisal of their classification as well as refinements in the diagnostic approaches used by pathologists. Sixty-two pituitary adenomas are described, and recent advances in this field are reviewed. Most of the patients were adults, but one of the adrenocorticotropic hormone (ACTH)-producing adenomas occurred in an 11-month-old infant. Endocrine-inactive tumors (43.5 per cent) were less common than hormone-producing tumors (56.5 per cent). Local invasion was most common in the former group, followed by ACTH-producing and other hormone-producing tumors. Ultrastructural features correlated with hormonal levels in the growth hormone(GH)-secreting tumors but not in the prolactin(LTH)- or ACTH-producing tumors. The formation of 7-nm filaments in the cytoplasm of tumor cells, corresponding to Crooke's hyaline change on light microscopy, was characteristic of ACTH-producing tumors. Ultrastructural changes in the ACTH granules suggested that the filaments may be derived from the feedback action of cortisol. Prior to surgery, a Rathke's cleft cyst and a chordoma were mistaken for endocrine-inactive pituitary adenomas. In two additional cases ectopic ACTH-producing tumors of lung clinically mimicked pituitary adenoma. Conversely, one pituitary adenoma mimicked sphenoid wing meningioma. Clinical, hormonal, and radiologic data and immunocytochemical and electron microscopic studies are needed for accurate pathologic interpretation and classification of pituitary adenomas.

Adenoma↗
PubMed1982

Cystic neoplasms of the pancreas: CT and sonography.

Cystic neoplasms of the pancreas are pathologically divided into macrocystic adenomas and microcystic adenomas, the former are considered a premalignant lesion and the latter without malignant potential. Five cases of cystic neoplasms are presented and the sonographic and/or computed tomographic features of microcystic and macrocystic adenoma are compared. A specific diagnosis can at times be suggested based on the computed tomography and sonography findings. In the proper clinical setting microcystic adenoma should be considered in the differential diagnosis of a pancreatic mass seen on sonography and computed tomography. Preoperative biopsy with appropriate pathologic staining can be performed and aid in directing appropriate therapy.

Adenocarcinoma↗