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Biomedical subjects

J D Martin

Publications and source records attributed to J D Martin.

At least 19 recordsLinked to original sources
PubMed1992

Extrathoracic carotid reconstruction: the subclavian-carotid artery bypass.

Although the predominant location of symptomatic carotid artery occlusive disease is the carotid bifurcation, proximal common carotid artery lesions cause similar symptoms. Common carotid artery lesions occur as isolated disease or in tandem with carotid bulb disease. Restoration of carotid artery inflow from subclavian based extraanatomic bypasses should provide adequate reconstruction of these lesions. To evaluate subclavian-carotid artery bypass, a retrospective review of all patients undergoing this procedure from Jan. 1, 1977, to Feb. 20, 1989, was performed. Twenty patients (14 men, 6 women) with a mean age of 60 years were treated. Fifteen patients (75%) were admitted with transient ischemic attacks. Five (25%) had nonfocal symptoms (e.g., dizziness, syncope). Arteriographic evaluation demonstrated severe proximal occlusive disease of the common carotid artery in all cases. Reconstruction bypasses were performed to the carotid bulb (45%), internal carotid artery (30%), and external carotid artery (25%). Four patients underwent endarterectomy of the internal carotid artery in conjunction with subclavian-carotid artery bypass. Bypass conduits included saphenous vein (75%) and prosthetic grafts (25%). Asymptomatic phrenic nerve neuropraxia was identified by postoperative chest radiography in four cases, with no resultant respiratory disease. No perioperative strokes occurred. One postoperative death (5%) resulted from a myocardial infarction. Long-term results were available for 18 patients (90%), with a mean follow-up of 50 months (range, 1 to 122 months). Four patients have died of causes unrelated to carotid vascular disease. Serial duplex scans have documented graft patency in all 18 patients. A single patient returned with focal neurologic symptoms as a result of a posterior circulation infarct.(ABSTRACT TRUNCATED AT 250 WORDS)

Arterial Occlusive Diseases↗
PubMed1991

Comparison of regulatory sequences and enhancer activities of SV40 variants isolated from patients with neurological diseases.

The genomic regulatory regions of human isolates of SV40 were compared by nucleotide sequencing and by biological assays of their transcriptional enhancers. SVAST is a defective genome and SVMEN an infectious genome molecularly cloned from human astrocytoma and meningioma, respectively (Krieg and Scherer, 1984). SVPML is an isolate from a case of progressive multifocal leukoencephalopathy (Weiner et al., 1972). SVAST contains a duplication of the regulatory region. One copy is virtually identical to that of SV40; the other bears a deletion of the minimal enhancer and is associated with an insertion of early/late sequences derived from the terminus of replication. The latter copy, together with its insertion, is inserted at nucleotide 4966 (SV40 number). SVMEN has an almost exact deletion of one of the 72-base-pair repeats of the natural SV40 enhancer. The regulatory sequences of SVPML were reported earlier (Martin, 1989). The enhancer activity in CV-1 cells of the lytic virus, SVPML, is 36% that of SV40. In contrast, the SVAST and SVMEN enhancers are more effective, being equal to or 64% that of SV40, respectively. The possibility that SVPML and SVAST/SVMEN originated from different variants of SV40 is discussed.

DNA, Viral↗
PubMed1991

Asymptomatic celiac and superior mesenteric artery stenoses are more prevalent among patients with unsuspected renal artery stenoses.

The prevalence of unsuspected renal artery stenosis among patients with peripheral vascular disease has been reported to be as high as 40%, but the prevalence of asymptomatic celiac and superior mesenteric artery stenoses in these patients is not known. The biplane aortograms of 205 male patients who were military veterans and had aneurysms or occlusive disease were independently reviewed, and medical records were studied to determine associated coronary disease, risk factors, and patient outcome. Fifty-six patients (27%) had a 50% or greater stenosis in the celiac or superior mesenteric artery, and seven patients (3.4%) had significant stenoses in both mesenteric arteries. Patients with celiac or superior mesenteric artery stenoses were older (p = 0.002) and had a higher prevalence of hypertension (p = 0.029) than those without significant mesenteric stenoses. Fifty of the 205 patients had significant renal artery stenoses, and 20 had advanced (greater than 75% diameter loss) renal stenoses. Ten of the 20 patients (50%) with advanced renal stenoses had a concomitant celiac artery stenosis, compared to 40 of the 185 patients (22%) who did not have advanced renal stenoses (p = 0.011). In the present study asymptomatic celiac or superior mesenteric artery stenoses were common among male veterans evaluated for peripheral vascular disease, but the prevalence of significant stenoses in both the celiac and superior mesenteric arteries was low. The prevalence of significant celiac stenosis was higher in patients with advanced (greater than 75%) renal artery stenoses who might be considered for prophylactic renal revascularization. Lateral aortography with evaluation of the celiac artery is always appropriate in these patients.

Age Factors↗
PubMed1991

Is routine CT scanning necessary in the preoperative evaluation of patients undergoing carotid endarterectomy?

To evaluate the usefulness of CT scanning before carotid endarterectomy, a prospective study was performed on 469 consecutive patients considered for carotid endarterectomy during a 5-year period. All patients underwent carotid duplex scanning and CT scanning before carotid arteriography. Two hundred thirty-seven patients (51%) had transient ischemic attacks, 109 (23%) had a prior stroke, and 122 (26%) were asymptomatic. Results of the CT scan were abnormal in 68 (62%) of the 109 patients with stroke. Fifty-one of the 360 patients (14%) without a clinical history of stroke had an abnormal CT scan outcome. Of patients with a stroke documented by CT scanning, 27 had lacunar infarcts, and 92 had cortical infarcts; these findings did not change surgical management in any patient. CT scanning did not reveal any unsuspected infarcts or tumors. Two hundred thirty carotid endarterectomies were performed on 206 patients. Forty-seven patients (23%) in the operative group had abnormal CT scan findings, but the scan did not influence operative decisions or timing in any case. Seventy-two patients (27%) in the nonoperative group had abnormal CT scan results, but CT scan findings did not exclude any patient from arteriography or surgery. Three perioperative strokes (1.3%) occurred. CT scan findings did not correlate with postoperative neurologic complications. Cost of CT scanning was one-half million dollars in our study alone. Routine CT scanning is unnecessary before carotid endarterectomy and is not cost-effective.

Adult↗
PubMed1990

A comparison of BKV, JCV, and SV 40 transcriptional enhancers in primate cells. Application of the two-phase partition assay for chloramphenicol acetyl transferase (CAT).

The activities of the transcriptional enhancers of the prototype human polyomaviruses, BKV (Dun) and JCV (MAD-1), were compared with that of the rhesus virus SV 40 in Old World African green monkey kidney cells (CV-1) and in New World owl monkey kidney cells (OMK). Enhancer activities were tested in CAT-expression plasmids. CAT activity in transfected cell extracts were measured by the novel two-phase partition assay. The activities of the BKV and JCV enhancers were 45% and 20% that of SV 40, respectively, in CV-1 cells. The effectiveness of each viral enhancer was less in OMK cells than in CV-1 cells, as would be expected if the viruses co-evolved with their natural hosts. In CV-1 cells, the BKV enhancer was more active than that of JCV, but in OMK cells the reverse was true. This result is significant in view of the fact that JCV, but not BKV, is oncogenic in owl monkeys.

Animals↗
PubMed1990

Application of the two-phase partition assay for chloramphenicol acetyl transferase (CAT) to transfections with simian virus 40-CAT plasmids.

The two-phase partition assay for chloramphenicol acetyl transferase (CAT) was tested for its applicability in transfection experiments involving CAT-expression plasmids containing simian virus 40 (SV40) transcriptional control elements. The assay was shown to be simple, sensitive, reproducible, and, with the modification described, cost-effective. However, CAT transfection experiments themselves gave highly variable results. Yields of CAT per microgram of protein in pSV2-CAT transfections of CV-1 cells varied by 60%. This variability could not be explained by variation in the quality of DNAs used, differences in growth states of the cells at transfection, the culture medium employed, or the time at which transfected cells were extracted for CAT assay.

Chloramphenicol O-Acetyltransferase↗
PubMed1990

Measures of concurrent validity and alternate-form reliability of the Test of Nonverbal Intelligence.

The subjects, 60 undergraduate students, were administered the Test of Nonverbal Intelligence (TONI) individually. The Shipley Institute of Living Scale was administered in small groups. A Pearson correlation of .56 was obtained for TONI Quotients, Forms A and B. TONI Quotients, Forms A and B, correlated with Shipley estimated WAIS--R IQ .50 and .46, respectively, and correlated to .71 and .64, with Shipley Total T scores, .52 and .44, respectively (corrected to .71 and .61), with Shipley Abstraction T scores, .51 and .42, respectively (corrected, .63 and .52), and with Shipley Vocabulary T scores .26 and .32, respectively (corrected to .63 and .52). TONI scores seem more closely related to Shipley Total and Abstraction scores than to Shipley Vocabulary.

Achievement↗
PubMed1990

Radical treatment of mal perforans in diabetic patients with arterial insufficiency.

Forty patients with diabetes mellitus and severe mal perforans underwent dorsal excision of the involved metatarsal head with primary closure of the plantar ulcer. Patients were screened before operation with noninvasive studies documenting pulse examination, ankle pressure index, and toe blood pressures. Fifteen of 40 patients (38%) had no palpable pedal pulses. Three patients had vascular reconstruction before metatarsal head resection. Mean toe pressure of the entire group was 135 +/- 35 mm Hg (range, 60 to 190), with six patients having a pressure less than 100 mm Hg. All patients had primary healing of the plantar wound and secondary healing of the dorsal incision with no amputations or readmissions for forefoot sepsis in the mean follow-up of 38.5 months (range, 2 to 54 months). In seven patients with recurrent ulcers, no relationship was found between measured indexes of forefoot perfusion and recurrence. However, all patients with recurrence were noncompliant in returning for follow-up orthotic care. This technique provides a means to ensure rapid healing of severe mal perforans while decreasing hospitalization, wound care, and periods of immobilization and is applicable in diabetic patients with arterial insufficiency and toe pressure of at least 60 mm Hg.

Blood Pressure↗
PubMed1989

Metabolism of androstenedione by placental microsomes in pregnancy hypertension.

The metabolism of [19-3H3]androstenedione by human placental microsomes was studied in vitro by radiometric analysis which distinguishes between 19-hydroxylation and elimination of the C-19 carbon. The ratio of the metabolic products tritiated water/tritiated formic acid is significantly greater for microsomes from patients with pregnancy hypertension when compared with normotensive pregnant women. This indicates that aromatization (2-hydroxylation) is deficient in pregnancy hypertension.

Androstenedione↗
PubMed1989

Regulatory sequences of SV40 variants isolated from patients with progressive multifocal leukoencephalopathy.

Variants of the simian polyomavirus SV40 have been associated in humans with a small number of cases of progressive multifocal leukoencephalopathy (PML). Genomic regulatory regions of two independent isolates, SVPML-1 and -2 [L.P. Weiner et al., N. Engl. J. Med. 286, 385 (1972)], were analyzed to determine if they had acquired any sequences that are present in the genome of the human polyomavirus JC (JCV), the primary causative agent of PML. As compared to SV40 DNA, 83% of SVPML-1 and -2 cloned DNAs contained an apparent deletion of about 30 base pairs in the restriction fragment containing the regulatory region (type alpha); 17% had a deletion of about 60 base pairs (type beta). The regulatory sequences were identical in all four clones representative of SVPML-1 and -2 type alpha grown in human and monkey cells. Thus the primary genomes of two isolates of SV40 from PML are identical in the region that is highly heterogeneous in JCV. The SVPML-alpha-DNAs have a net deletion of 30 base pairs and rearrangements within the transcriptional enhancer. The transcriptional promoter and origin of DNA replication is unaltered from that of SV40. Therefore the human neurotropism of SVPML appears to be a consequence of important rearrangements of SV40 sequences rather than acquisition of JCV-like sequences.

Base Sequence↗
PubMed1989

Plasma 19-hydroxyandrostenedione and androstenedione levels in hydatidiform moles and early pregnancies with and without hypertensive diseases.

Because of the association of preeclampsia with hydatidiform mole, and since levels of 19-hydroxyandrostenedione (19-OH-A) and androstenedione (A) are raised in hypertensive diseases of pregnancy, we compared plasma 19-OH-A and A in hydatidiform mole patients with control early pregnant women. Both steroids were significantly elevated in 27 patients with partial or complete hydatidiform moles, as compared with the levels in 36 control pregnancies at similar stages of gestation.

Androstenedione↗
PubMed1988

Familial parkinsonism, apathy, weight loss, and central hypoventilation: successful long-term management.

We report a third family with six members with features of the syndrome of familial parkinsonism, depression, weight loss, and central hypoventilation. Patients with this syndrome typically die suddenly, presumably from central respiratory failure. Following multiple respiratory arrests, one affected member was successfully managed with aggressive pulmonary care, tracheostomy, and intermittent home mechanical ventilation, which, combined with carbidopa/levodopa, allowed for a functional lifestyle with improvement in apathy, mobility, and nutritional status.

Body Weight↗
PubMed1987

Rorschach correlates of state and trait anxiety in college students.

This study was done to determine whether Elizur's anxiety scoring (AL) for Rorschach content was correlated to scores on Spielberger's State-Trait Anxiety Inventory (STAI). The definition of anxiety presented by Elizur implies that his technique measures anxiety as a long-term, relatively stable personality characteristic rather than a transitory emotional state, but no research has shown whether AL was correlated with state and/or trait anxiety as defined and measured by Spielberger. The State-Trait Anxiety Inventory was administered in small groups to 40 college students with a repeated measure of STAI State-anxiety and the Rorschach given individually following a delay of at least five days. Analysis indicated that the STAI Trait-anxiety measure correlated significantly with AL. Test-retest correlations for STAI State-anxiety measures and STAI State- and Trait-anxiety measures obtained in the same testing session were significant. State-anxiety scores obtained just prior to Rorschach testing were related to STAI Trait-anxiety scores and initial STAI State-anxiety scores correlated with AL.

Adolescent↗
PubMed1986

The influence of estrogen and progesterone receptors on survival in patients with carcinoma of the uterine cervix.

The prognostic value of estrogen receptors (ER) and progesterone receptors (PR) was studied in 246 women with primary carcinoma of the uterine cervix. In addition to the receptor status information on tumor stage, histological type, age at operation, and menopausal status was recorded and analyzed. If the patient died the cause of death was ascertained. The median survival time for the 97 patients who died was 15 months and the survivors were followed for an average of 34 months. The survival curve was compared with an age, sex, and year of death matched West-Australian population. The survival curves for patients with ER+ or ER- and PR+ or PR- tumors were virtually indistinguishable. Overall survival in patients with cervical carcinoma is not influenced by the receptor status or the receptor concentration of the carcinoma.

Carcinoma↗
PubMed1985

Differences in regulatory sequences of naturally occurring JC virus variants.

The regulatory region was sequenced for DNAs representative of seven independent isolates of JC virus, the probable agent of progressive multifocal leukoencephalopathy. The isolates included an oncogenic variant (MAD-4), an antigenic variant (MAD-11), and two different isolates derived from the urine (MAD-7) and from the brain (MAD-8) of the same patient. The representative DNAs were molecularly cloned directly from diseased brain tissue and from human fetal glial cells infected with the corresponding isolated viruses. The regulatory sequences of these DNAs were compared with those of the prototype isolate, MAD-1, sequenced previously (R. J. Frisque, J. Virol. 46:170-176, 1983). We found that the regulatory region of JC viral DNA is highly variable due to complex alterations of the previously described 98-base-pair repeat of MAD-1 DNA. On the basis of these alterations, there are two general types of JC virus. There were no consistent alterations in regulatory sequences which could distinguish brain tissue DNAs from tissue culture DNAs. Furthermore, for each isolate except MAD-1 (R. J. Frisque, J. Virol. 46:170-176, 1983), the regulatory regions of brain tissue and tissue culture DNAs were not identical. The arrangement, sequence, or both of potential regulatory elements (TATA sequence, GGGXGGPuPu, tandem repeats) of JC viral DNAs are sufficiently different from those in other viral and eucaryotic systems that they may effect the unique properties of this slow virus.

Animals↗