Biomedical subjects

S E Martin

Publications and source records attributed to S E Martin.

At least 91 records · Page 5Linked to original sources

PubMed1991

Coronary vasoconstriction induced by vasopressin. Production of myocardial ischemia in dogs by constriction of nondiseased small vessels.

BACKGROUND: We studied the effect of intracoronary administration of arginine-8-vasopressin on blood flow in nondiseased coronary arteries and determined whether this vasoconstriction was severe enough to produce ischemia in 30 dogs. METHODS AND RESULTS: In group 1 (n = 6), after vasopressin administration coronary blood flow was decreased by 41% (p less than 0.002) without changes in heart rate or aortic pressure, and left ventricular ejection fraction measured by radionuclide angiocardiography was decreased by 18% (p less than 0.0005). In group 2 (n = 6), ischemia was confirmed by measurement of transmural pH changes. Administration of vasopressin decreased subendocardial pH of the infused zone from 7.40 +/- 0.03 to 7.31 +/- 0.07 (p less than 0.01). The subendocardial pH of the zone not infused with vasopressin did not change. To overcome the intrinsic regulation of blood flow, operating primarily in small coronary arteries, we hypothesized that vasopressin must increase resistance primarily in large rather than small coronary arteries. After intracoronary infusion in group 3 (n = 6), however, most (94%) of the increase in resistance during vasopressin administration was explained by an increase of resistance in small coronary arteries. In group 4 (n = 9), vasopressin decreased coronary blood flow by 50% and decreased local shortening by 90% at a time when systemic hemodynamics were unchanged. Coronary constriction induced by vasopressin, or the recovery from it, also was not altered by cyclooxygenase blockade. CONCLUSIONS: Thus, vasopressin produces myocardial ischemia by constricting small, nondiseased coronary arteries severely enough to overcome the competition from normal coronary regulation, and this ischemic event is not mediated by prostaglandin products.

Animals↗

PubMed1991

Retrospective evaluation of patient-controlled analgesia use in a large teaching institution.

Because of a significant increase in the number of patients receiving patient-controlled analgesia (PCA) therapy at our institution, we conducted a review of PCA use. Our objectives were to determine if a PCA recording document (monitoring form) could be used to identify potential problems associated with PCA therapy and to identify measures that could be taken to improve analgesic therapy with this method of administration. The PCA recording document for each patient was reviewed retrospectively to identify patients suspected of having problems with the therapy. Three criteria addressing duration of therapy, change in prescribed narcotic, and respiratory rate were used to evaluate PCA therapy. The standard was set at 100 percent. Complete patient records were reviewed for those patients not meeting the standard to determine whether problems actually existed. PCA recording documents were reviewed for 518 patients. Sixty-one patients did not meet the standard. Of these 61 patients, 41 (67.2 percent) were found to have problems with PCA therapy. Suspected adverse reactions occurred in 27 of these 41 patients and 14 experienced inadequate pain control. Nausea and vomiting were the most prevalent adverse reactions. Our results indicate that PCA therapy is discontinued in many patients because of inadequate pain relief and suspected narcotic-induced nausea and vomiting. To improve analgesic therapy, clinicians should be reeducated regarding ways to optimize analgesic therapy, and a prospective PCA monitoring service should be considered.

Aged↗

PubMed1991

Co-expression of four intermediate filament subclasses in childhood glial neoplasms.

Immunohistochemical analysis of intermediate filament (IF) proteins was performed on frozen sections of 16 childhood glial tumors using a library of 10 antigen-specific IF protein directed monoclonal antibodies (MoABs) and a four-step biotin-streptavidin-alkaline phosphatase conjugated antigen detection immunocytochemical technique. Human glial fibrillary acidic protein (GFAP) and vimentin were expressed in all brain tumors. High molecular weight (200 kDa) neurofilament (NF-H) protein was expressed in 15 out of 16 tumors; medium molecular weight (160 kDa) neurofilament (NF-M) in seven out of 16 tumors; and low molecular weight (68 kDa) neurofilament (NF-L) in five out of 16. Positive acidic keratin reactivity was found in five out of 16 tumors using MoAB AE1. Expression of a keratin pair was detected with MoAB AE2 in five out of 16 tumors. A second keratin pair in 14 out of 16 glial tumors was demonstrated with MoAB AE3. Immunostaining with AE5 defined the expression of another basic keratin (64 kDa) in nine out of 16 glial tumors. Finally, in 14 out of 16 astrocytomas an individual 51 kDa acidic keratin (detected with MoAB AE8) was expressed. Glial tumor cells contain cell lineage specific and nonspecific IF proteins in the following IF pattern: AE3+, AE8+, GFAP+, vimentin+, and NF-H+. The heterogenous composition of these cytoskeletal IF proteins in childhood glial tumors may reflect a direct stage dependent correlation with their neoplastic transformation.

Adolescent↗

PubMed1990

Detection of c-K-ras mutations in fine needle aspirates from human pancreatic adenocarcinomas.

Formalin-fixed paraffin-embedded tissue specimens obtained by fine needle aspiration of pancreatic masses from 47 patients were examined retrospectively for cytology and the presence of mutant c-K-ras oncogenes. Point mutations of c-K-ras in codon 12 were detected by RNA-DNA RNAse A mismatch cleavage after in vitro DNA amplification of the cellular c-K-ras sequences by the polymerase chain reaction. Of the 36 patients with pancreatic adenocarcinoma, mutant c-K-ras oncogenes were detected in 18 of 25 (72%) with malignant cytologies, 2 of 8 (25%) with atypical cytologies, and 0 of 3 with benign aspiration cytologies. The remaining 11 patients without pancreatic adenocarcinomas did not have mutant c-K-ras genes detectable by the assay. The diagnosis of pancreatic adenocarcinoma was based upon clinical follow-up. The presence of mutant c-K-ras oncogenes did not significantly affect survival in the patients studied. Mutant c-K-ras genes were found at the time of initial clinical presentation in the majority of pancreatic adenocarcinomas, suggesting an important role of the mutation in oncogenesis. In conjunction with cytology, our approach represents an application for cancer diagnosis at the molecular genetic level.

Adenocarcinoma↗

PubMed1990

Alimentary tract cytopathology in human immunodeficiency virus infection: a review of experience in Los Angeles.

In the past decade, over 100,000 cases of the acquired immunodeficiency syndrome (AIDS) have been reported in the United States. Conservative estimates suggest that 1.5 million people are infected with the human immunodeficiency virus (HIV), the etiologic agent of AIDS. Major metropolitan areas, such as Los Angeles, have experienced a rapid increase in the number of AIDS cases. At the Los Angeles County-University of Southern California Medical Center, we have gained significant insight into the cytologic findings associated with HIV infection. Based on our experience, we herein review the technical and morphologic evaluation of alimentary tract cytology specimens from this patient population.

AIDS-Related Complex↗

PubMed1990

Catalase, superoxide dismutase, and hemolysin activities and heat susceptibility of Listeria monocytogenes after growth in media containing sodium chloride.

The activities of catalase, superoxide dismutase, and a thiol-activated hemolysin produced by four strains of Listeria monocytogenes propagated in media containing various concentrations of sodium chloride were examined. L. monocytogenes 7644 showed an increase in catalase, superoxide dismutase, and thiol-activated hemolysin activities when grown in a medium containing 2.5% (wt/vol) NaCl followed by a decrease in activities when propagated in media containing salt concentrations higher than 2.5%. L. monocytogenes LCDC 81-861 demonstrated enhanced catalase activity when grown in media containing NaCl ranging from 1.5 to 4.6% and increased superoxide dismutase activity when propagated in media containing 1.5 to 3.5% NaCl. L. monocytogenes LCDC 81-861 did not exhibit any detectable hemolysin activity under the conditions tested. After growth in various NaCl-containing media, both strains were subjected to sublethal heat injury for 30 min at 55 degrees C. L. monocytogenes LCDC 81-861 showed increased sensitivity to the heat treatment when grown in media containing 4.6 and 6.5% NaCl, whereas L. monocytogenes 7644 did not exhibit enhanced heat lability.

Catalase↗

PubMed1990

Prospective evaluation of blind brushing of the esophagus for Candida esophagitis in patients with human immunodeficiency virus infection.

We prospectively evaluated the diagnostic value of blind brushing of the esophagus via nasogastric tube in 66 patients with human immunodeficiency virus (HIV) infection [acquired immune deficiency syndrome (AIDS) (N = 59), or AIDS-related complex (ARC), (N = 7)] complaining of odynophagia and/or dysphagia. Brushings were obtained between 20 and 35 cm from the incisors. Patients then underwent upper endoscopy with directed brushings and biopsies; esophageal lavage was also done in the first 40 patients. Candida esophagitis was defined as an abnormal appearance of the esophageal mucosa, together with microscopic evidence of pseudohyphae in the endoscopic brushings or invasive candidiasis on biopsy. The presence of oral thrush was also recorded. Candida esophagitis was present in 28 (42%) of the 66 patients. Blind brushings diagnosed candidiasis in 27/28 cases and produced five false positives (sensitivity 96%, specificity 87%). Blind brushing of the esophagus was significantly more sensitive than the presence of oral thrush for the diagnosis of esophageal candidiasis (p = 0.02). Oral thrush was found in only 20/28 cases of Candida esophagitis and in eight patients without Candida (sensitivity 71%, specificity 79%). Esophageal lavage yielded Candida in all cases (sensitivity 100%) but had a poor specificity (64%). We conclude that blind brushing of the esophagus is a rapid, safe, and economical way to diagnose Candida esophagitis in patients with AIDS. This procedure can be performed by primary care physicians with minimal loss of sensitivity and specificity as compared to endoscopy.

Acquired Immunodeficiency Syndrome↗

PubMed1989

Detection of human papillomavirus DNA in fine-needle aspirations of metastatic squamous-cell carcinoma of the uterine cervix using the polymerase chain reaction.

Routinely processed fine-needle aspirations of metastatic squamous-cell carcinoma (SCC) were analyzed for human papillomavirus type 16 (HPV-16) using the polymerase chain reaction (PCR), an in vitro DNA amplification method. HPV-16 DNA was detected in five of seven (71%) metastases from SCC of the uterine cervix. In two cases in which the primary tumor was available for comparison, the HPV-16 DNA content of the primary tumor and of the metastasis was identical. HPV-16 was not found in a metastatic SCC from the lung or in a metastatic nasopharyngeal SCC. These findings demonstrate that HPV-16 DNA sequences can be readily detected in routinely processed fine-needle aspirations using the polymerase chain reaction. The finding of HPV-16 DNA in a metastasis may serve to direct a search for a primary site of origin.

Adolescent↗

PubMed1989

Primary mucosal malignant melanoma: an immunohistochemical study of 12 cases with comparison to cutaneous and metastatic melanomas.

Immunohistochemical analysis of 40 formalin-fixed, paraffin-embedded malignant melanomas (12 primary mucosal, 16 primary cutaneous, and 12 metastatic cutaneous) was performed to study the possible differences in immunostaining profiles according to location. The majority of melanomas were reactive with a polyclonal antibody to S100 protein (P-S100; 85%), a monoclonal melanoma-specific antibody (HMB-45; 88%), and a monoclonal antibody to vimentin (90%), and there were no differences in staining profiles for these antibodies by anatomic location. In contrast, while 13 of 16 cutaneous melanomas (81%) and ten of 12 metastatic melanomas (83%) were reactive with a monoclonal antibody to S100 protein (MoAb-079), only five of 12 mucosal tumors (42%) showed positive staining for MoAb-079. Similarly, 14 cutaneous melanomas (88%) and 11 metastatic melanomas (92%) showed positive staining for neuron specific enolase (NSE), while only four mucosal melanomas (33%) were NSE-positive. Of the 40 melanomas, all but two were reactive with either P-S100, MoAb-079, or HMB-45. These findings suggest that MoAb-079 and NSE may be less sensitive markers than P-S100 and HMB-45 for routinely processed mucosal melanomas as compared with cutaneous and metastatic tumors.

Antibodies, Monoclonal↗

PubMed1989

Interfollicular small lymphocytic lymphoma: the diagnostic significance of pseudofollicles.

The pathologic, immunologic, and clinical features of 25 cases of interfollicular (IF) small lymphocytic lymphoma (SLL) characterized by pseudofollicles (PFs) in the IF region of the lymph nodes and by multiple reactive follicles (RFs) were examined. IFSLL is characterized morphologically by variable numbers and sizes of prolymphocytes (nuclei showing one centrally located prominent nucleolus) in the PFs and by small round lymphocytes in the IF region. The lymph nodes in our cases had multiple RFs (100%) and patent or partially patent sinuses (72%), with moderate expansion of the IF region (48%) and typically absent or minimal perinodal infiltration (48%). In 48% of the cases, the PFs surrounded the RFs, producing a pseudo-mantle zone pattern. Immunologic study showed the medium and large prolymphocytes to be mildly LN 1- and LN 2-positive, whereas the small prolymphocytes and lymphocytes were LN 1-negative and moderately LN 2-positive. Few cells in the IF region stained with UCHL-1 antibody. These data indicate the marked preponderance of the non-follicular center cell type of B cells in the IF areas. In all 11 cases tested, a monoclonal B cell population was found. The mean age of the patients was 62 years, with a male to female ratio of 1:1.7. B symptoms were present in 20% of the patients. Nineteen percent of the patients had clinical stage I or II disease, whereas 81% had stage IV disease. The median absolute lymphocyte count was 3,239 X 10(6), with a range of 767 to 13,770 X 10(6) cells/L. In six cases, the lymphocyte count was above 4,000 X 10(6), and in no case was it more than 15,000 X 10(6). It was difficult to distinguish these cases of IFSLL from lymphadenitis and other non-Hodgkin's lymphomas because it was difficult to recognize the subtle PF pattern in the presence of a partially preserved lymph node architecture. Because of the partially retained lymph node architecture and the expansion of the IF region by PFs, this lymphoma is thought to originate from the IF small B lymphocytes, which displayed an in situ growth pattern. Moreover, because of the predominant disease in the lymph nodes and the similarity of features in PFs and follicles, we conclude that IFSLL is a disease that is primary to the lymph nodes. IFSLL should be distinguished from mantle zone lymphoma and chronic lymphocytic leukemia.

Adult↗

PubMed1989

Intermediate filament expression in astrocytic neoplasms.

Immunohistochemical analysis of 30 paraffin-embedded astrocytic neoplasms was performed to correlate the expression of intermediate filament proteins with histologic subtype. Each tumor was studied with monoclonal antibodies to keratin, vimentin, desmin, 200-kd neurofilament protein, and glial fibrillary acidic protein (GFAP). Immunoreactivity with the anti-keratin monoclonal antibodies AE1 and AE3 was demonstrated in 24 cases (80%) including 4 of 6 (66%) well-differentiated astrocytomas (WDAs), 10 of 12 (83%) anaplastic astrocytomas (ANAs), and 10 of 12 (83%) glioblastomas multiforme (GBMs). These cases were further studied with the monoclonal antikeratin antibodies 34 beta E12 and 34 beta H11. Of the 24 AE1/AE3-positive cases, 14 (58%) reacted with 34 beta E12. None of the cases was reactive with 34 beta H11. Vimentin expression was demonstrated in 24 cases (80%), including 2 of 6 (33%) WDAs, 11 of 12 (92%) ANAs, and 11 of 12 (92%) GBMs. Coexpression of keratin and vimentin was observed in 20 cases (67%), including 2 of 6 WDAs, 9 of 12 (75%) ANAs, and 9 of 12 (75%) GBMs. Immunoreactivity with GFAP antibody was present in all 30 (100%) cases, but none of the tumors was reactive with antibodies to desmin or 200-kd neurofilament protein. These findings demonstrate that expression of both keratin and vimentin intermediate filaments is common in astrocytic neoplasms regardless of histologic grade.

Astrocytoma↗

PubMed1989

Coronary vascular responses to chemical stimulation of abdominal visceral organs.

Topical application of bradykinin or capsaicin to abdominal visceral organs produces adrenergically mediated, reflex increases in mean arterial pressure and cardiac work. To determine the effects on coronary blood flow, the left main coronary artery of anesthetized cats was perfused at constant pressure with a servo-controlled pump. Cardiovascular parameters were measured during reflex stimulation before and after beta-adrenoceptor blockade with propranolol. Before propranolol, reflex activation led to increases in the double product and myocardial oxygen consumption, usually accompanied by increases in coronary blood flow. However, in 32% of the observations, decreases in flow were observed. During beta-adrenoceptor blockade, reflex stimulation produced increases in cardiac work, whereas the increases in coronary blood flow were attenuated. Marked decreases in average coronary blood flow were observed more frequently (42%). In the presence of propranolol, contrary to the unblocked state, increases in oxygen consumption were achieved by increased oxygen extraction. Subsequent alpha-adrenoceptor blockade with phentolamine abolished all reflex changes. These data indicate that during stimulation of abdominal visceral chemoreceptors, the major coronary response is vasodilation, but in a sizable fraction of cases, abdominal visceral reflexes can produce sympathetically mediated coronary vasoconstriction.

Animals↗

PubMed1989

Coronary constriction due to neuropeptide Y: alleviation with cyclooxygenase blockers.

Intra-arterial administration of neuropeptide Y (NPY), a peptide endogenous to sympathetic nerves, increases coronary vascular resistance by 30-40%. To test whether blockade of prostaglandin synthesis altered the severity of the NPY-induced coronary vasoconstriction, dogs (n = 25) were anesthetized and instrumented to record hemodynamic parameters. In control animals (n = 11) paired infusions of NPY (42 nmol/3 min) were given at 0 and 120 min. NPY produced similar increases in coronary resistance by 10 min, 31 +/- 7% (mean +/- SD) with the first dose vs. 32 +/- 12% with the second dose. The increases in resistance were due to an initial decrease in coronary flow (10 +/- 6%) followed by a prolonged increase in aortic pressure (15-20% over 20 min). Each infusion of NPY decreased heart rate (-10 +/- 7%) but did not alter left ventricular dP/dt. The effects of NPY lasted 40-60 min. In a separate group, a cyclooxygenase inhibitor (COI), indomethacin (n = 6) or ibuprofen (n = 8), was given 1 h before the second dose of NPY. The increases in coronary resistance were blunted significantly after cyclooxygenase blockade from a predrug value of 36 +/- 13 to 19 +/- 12%. In these treated animals, the decrease (-12 +/- 6%) in coronary blood flow seen with the first dose of NPY was prevented (4 +/- 14%) during the second dose (P less than 0.05). Of the two drugs, ibuprofen appeared to restore coronary flow more than did indomethacin. Neither drug affected the base line or the NPY-elicited changes in aortic pressure, heart rate, dP/dt, or myocardial oxygen demands.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

Research note: the response of the clergy to spouse abuse in a suburban county.

An attempt was made to study the response of religious organizations to spouse abuse in a suburban county in the state of Maryland. Clergy members representing a variety of denominations from 143 churches and synagogues were surveyed. The presence of an ongoing problem-oriented discussion group as part of clergy functions was positively related to the identification of spouse abuse. More than half of the responding clerics acknowledged the need to improve efforts in addressing spouse abuse. Victim reticence to seek help, and lack of information about state law, legal options, and programs for spouse abusers were identified as major factors hampering response. Recommendations are made to improve linkages between the clergy and other involved community groups.

Attitude↗

PubMed1988

Stereotaxic biopsy diagnosis of central nervous system lymphoma.

Twelve cases of central nervous system lymphoma diagnosed by stereotaxic brain biopsy are reviewed to determine the most effective method to establish the diagnosis given the small amount of tissue obtained by this technique. The stereotaxic biopsy material was examined cytologically, histologically, and immunocytochemically. The diagnosis was established by a smear made at the time of biopsy in eight cases. Histologic sections were diagnostic of lymphoma in 11 of 12 cases. Accurate classification according to the Working Formulation was possible in six cases, with diagnosis of diffuse small non-cleaved non-Burkitt's in three, large cell immunoblastic in two, and mixed small and large cell type in one. Five additional cases were diagnosed as high-grade lymphoma but could not be further subclassified because of the small biopsy size or formalin fixation. Immunocytochemical stains for lymphoid markers on paraffin-embedded material confirmed the diagnosis in ten cases, and, in one of these, the demonstration of monoclonality on air-dried cytospins identified an atypical polymorphous lymphocytic population as neoplastic.

Adult↗

PubMed1988

Catalase and superoxide dismutase activities after heat injury of Listeria monocytogenes.

Four strains of Listeria monocytogenes were examined for catalase (CA) and superoxide dismutase (SOD) activities. The two strains having the highest CA activities (LCDC and Scott A) also possessed the highest SOD activities. The CA activity of heated cell extracts of all four strains examined decreased sharply between 55 and 60 degrees C. SOD was more heat labile than CA. Two L. monocytogenes strains demonstrated a decline in SOD activity after heat treatment at 45 degrees C, whereas the other two strains demonstrated a decline at 50 degrees C. Sublethal heating of the cells at 55 degrees C resulted in increased sensitivity to 5.5% NaCl. Exogenous hydrogen peroxide was added to suspensions of L. monocytogenes; strains producing the highest CA levels showed the greatest H2O2 resistance.

Catalase↗

PubMed1988

C5a decreases regional coronary blood flow and myocardial function in pigs: implications for a granulocyte mechanism.

Granulocytes cause some of the pathophysiological effects associated with the capillary no-reflow phenomenon during ischemia and in ischemia-reperfusion injury. However, no study has examined the consequences of in vivo granulocyte activation during normal perfusion pressures. In this study, we examined the effects of intracoronary administration of the complement component C5a, which is known to be a potent granulocyte activating factor. Nine open-chest, anesthetized pigs were instrumented to monitor regional coronary blood flow and segment shortening, left ventricular dP/dt, heart rate, and pulmonary artery and aortic blood pressures and to sample arterial and regional coronary venous blood for oxygen content and complete blood counts. Intracoronary infusion of human or porcine C5a in doses ranging from 10 to 500 ng produced a significant reduction in regional coronary blood flow and myocardial function. Although perfusion pressure and heart rate remained constant, venous oxygen content fell, indicating an imbalance between myocardial oxygen supply and demand. In addition, the arteriovenous difference of white blood cells was increased significantly after anaphylatoxin infusion, indicating intravascular trapping in the myocardium. Granulocytes accounted entirely for the differences in leukocyte counts because no significant changes in platelet, lymphocyte, or hematocrit levels were observed. Injection of vehicle alone did not alter any of the monitored variables.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1988

Hepatic hyaline globules associated with passive congestion.

We describe the presence of hyaline globules in liver associated with hepatic congestion. These globules were present in hepatocytes in 15% of 100 adult autopsies. They are periodic acid-Schiff (PAS)-positive and diastase-resistant by light microscopy, and in one case examined by electron microscopy, contained microfibrillar material with occasional rod-shaped inclusions. The majority of them stained positively for fibrinogen and alpha 1-antitrypsin by immunohistochemical methods. Of possible etiologies, the globules appear most probably as phagosomes containing imbibed serum proteins under conditions of increased sinusoidal pressure with passive congestion. They are more common than generally realized, when compared with other reported forms of nonglycogenic hyaline globules in liver. They must be distinguished from alpha 1-antitrypsin-disease globules.

Humans↗