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J Pfister

Publications and source records attributed to J Pfister.

At least 19 recordsLinked to original sources
PubMed1999

A comparison of an A1 adenosine receptor agonist (CVT-510) with diltiazem for slowing of AV nodal conduction in guinea-pig.

1. The purpose of this study was to compare the pharmacological properties (i.e. the AV nodal depressant, vasodilator, and inotropic effects) of two AV nodal blocking agents belonging to different drug classes; a novel A1 adenosine receptor (A1 receptor) agonist, N-(3(R)-tetrahydrofuranyl)-6-aminopurine riboside (CVT-510), and the prototypical calcium channel blocker diltiazem. 2. In the atrial-paced isolated heart, CVT-510 was approximately 5 fold more potent to prolong the stimulus-to-His bundle (S-H interval), a measure of slowing AV nodal conduction (EC50 = 41 nM) than to increase coronary conductance (EC50 = 200 nM). At concentrations of CVT-510 (40 nM) and diltiazem (1 microM) that caused equal prolongation of S-H interval (approximately 10 ms), diltiazem, but not CVT-510, significantly reduced left ventricular developed pressure (LVP) and markedly increased coronary conductance. CVT-510 shortened atrial (EC50 = 73 nM) but not the ventricular monophasic action potentials (MAP). 3. In atrial-paced anaesthetized guinea-pigs, intravenous infusions of CVT-510 and diltiazem caused nearly equal prolongations of P-R interval. However, diltiazem, but not CVT-510, significantly reduced mean arterial blood pressure. 4. Both CVT-510 and diltiazem prolonged S-H interval, i.e., slowed AV nodal conduction. However, the A1 receptor-selective agonist CVT-510 did so without causing the negative inotropic, vasodilator, and hypotensive effects associated with diltiazem. Because CVT-510 did not affect the ventricular action potential, it is unlikely that this agonist will have a proarrythmic action in ventricular myocardium.

Action Potentials↗
PubMed1998

HIV seroprevalence among male prison inmates in the Wisconsin Correctional System.

OBJECTIVE: To estimate HIV seroprevalence and the acceptance of voluntary HIV testing among male inmates entering the Wisconsin Correctional System during July 1, 1994-June 30, 1995, and compare these estimates with similar data obtained in 1987-1988. METHODS: A blinded HIV seroprevalence survey concurrent with a review of voluntary HIV antibody testing records. RESULTS: HIV test results were obtained for 3,681 (89%) male prison entrants during the study period; 26 (0.7%) were HIV-1 seropositive. Based on this estimate and the total number of male prison entrants (4,134), an estimated 29 HIV-1 seropositive male inmates entered the Wisconsin Correctional System during the study period. Eighty-four percent of all inmates were tested voluntarily. Among inmates testing HIV-1 seropositive, 69% were tested voluntarily. CONCLUSIONS: These data suggest that HIV-1 seroprevalence among male prison inmates in Wisconsin is low, and is unchanged from the late 1980s; however, a large increase in the prison population has resulted in a substantial increase in the absolute number of HIV-1 seropositive inmates entering the correctional system. Although overall acceptance of voluntary HIV testing is high, nearly one third of HIV-1 seropositive inmates declined voluntary HIV testing.

AIDS Serodiagnosis↗
PubMed1998

Surgical treatment of "steal syndrome" induced by arteriovenous grafts for hemodialysis.

OBJECTIVE: A rare but serious complication of angioaccess surgery for hemodialysis is the so called steal syndrome presenting as ischemia distal to an arteriovenous fistula. The main problem of various surgical techniques to correct steal is subsequent thrombosis of the fistula or persistence of distal ischemia. INTERVENTIONS: This paper describes an unknown technique for correction of ischemic steal consisting of ligation of the artery just distal to the take-off of the fistula and arterial bypass from the artery proximal to the take-off of the fistula to the artery distal to ligation. PATIENTS: Six patients with chronic renal insufficiency (3 male, 3 female) with patent upper arm cephalic fistulas presented with severe hand ischemia. RESULTS: Symptoms improved in all 6 patients immediately after operation. Successful hemodialysis could be maintained using the original fistula. CONCLUSIONS: The described technique is maybe the procedure of choice for the correction of fistula induced ischemic steal.

Adult↗
PubMed1997

Intracellular staining of angiotensin receptors in the PVN and SON of the rat.

Our immunocytochemical results demonstrate the presence of angiotensin AT1 receptors in the cytoplasm and at the cell membrane in paraventricular and supraoptic neurons of the rat hypothalamus. The reaction product had a punctate appearance. We found no staining in the cell nucleus. Similar results were obtained with an anti-idiotypic antibody to angiotensin II.

Animals↗
PubMed1997

Chronic calcifying tendinitis of the shoulder-therapy by percutaneous needle aspiration and lavage: a prospective open study of 62 shoulders.

In an open study the therapeutic value of percutaneous needle aspiration and lavage performed in local anaesthesia under image intensifier control in patients with chronic calcifying shoulder tendinitis was investigated. 60 patients (62 shoulders) were included in the study. The average age was 48 years, and the median duration of shoulder pain and calcification was 24 months and 7 months respectively. The right shoulder was affected in 34 and the left in 24 patients; two patients had painful calcifications in both shoulders. In 47% X-ray showed calcium deposits in the contralateral shoulder. 77% of the painful deposits projected on the supraspinatus tendon and in most cases image intensifier examination showed multiple calcifications. Calcareous material could be removed by needle aspiration and lavage in 76% of all cases. There was no correlation regarding the preferred working hand and the side of calcifying tendinitis. X-ray controls performed after 2 months revealed a significant reduction of the size of calcifications. The clinical follow-up 2 and 6 months after needling showed a significant reduction of global pain intensity. There were also significant improvements in the areas of pain on movement, pain at night and impairment of sleep. Clinical success was independent of the radiological aspect of the calcifications.

Adult↗
PubMed1995

Laptop meralgia.

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Adult↗
PubMed1995

1,3-Dipropyl-8-[2-(5,6-epoxy)norbornyl]xanthine, a potent, specific and selective A1 adenosine receptor antagonist in the guinea pig heart and brain and in DDT1MF-2 cells.

The objective of this study was to characterize the adenosine receptor (AdoR) antagonistic properties of a newly synthesized alkylxanthine, 1,3-dipropyl-8[2-(5,6-epoxy)norbornyl]xanthine (ENX), and compare them to those of 1,3-dipropyl-8-(cyclo-pentyl)xanthine (CPX), 1,3-dipropyl-8-(3-noradamantyl)xanthine (NAX) and (+/-)-N6-endo-norbornan-2-yl-9-methyladenine (N-0861). The potencies and selectivities of ENX, CPX, NAX and N-0861 were determined by functional studies of guinea pig isolated perfused hearts, and by radioligand binding assays for A1 and A2a AdoRs in the guinea pig forebrain and striatum. ENX competitively antagonized A1 AdoR-mediated prolongations of atrioventricular nodal conduction time caused by Ado or by 2-chloro-N6-cyclopentyladenosine, but not those caused by carbachol (0.14 microM) or MgCl2 (3 mM). Schild analysis of 2-chloro-N6-cyclopentyladenosine-antagonist competition curves yielded pA2 values for ENX, CPX and NAX of 8.45 +/- 0.19, 8.55 +/- 0.28 and 8.79 +/- 0.15, respectively. ENX (30 microM) and N-0861 (30 microM) did not attenuate the A2 AdoR-mediated increase in coronary conductance caused by adenosine. CPX and NAX attenuated the coronary vasodilation caused by adenosine with IC50 values of 1.5 and 7.1 microM, respectively. Radioligand binding assays revealed that ENX, CPX and NAX and N-0861 had a 400-, 209-, 110- and 10-fold greater affinity, respectively, for A1 than for A2a AdoRs of guinea pig brain membranes. Thus, ENX was equipotent with CPX and NAX and more potent than N-0861 (pA2 = 6.2) as an antagonist at A1 AdoRs, but had lower affinity for A2 AdoRs in guinea pig hearts and brain striatum than did either CPX or NAX. In DDT1 MF-2 cells, all three alkylxanthines had similar affinities for A1 AdoRs, whereas the affinity of N-0861 for A1 AdoRs was significantly lower. ENX appears to be the most A1 AdoR subtype-selective of the alkylxanthine class of AdoR antagonists reported to date.

Adenosine↗
PubMed1994

[Osteoporosis screening--indications for bone densitometry].

Osteoporosis is a major public health problem because of increasing prevalence and the cost of related morbidity, especially fractures of the spine and hip. The perimenopausal evaluation of risk patients by assessment of clinical risk factors and bone-mass measurements are used to select patients for prevention of postmenopausal and age-associated bone loss. The value of bone-mass for prediction of fracture-risk and the clinical significance of bone-densitometry for patient management is reviewed. Four essential clinical indications for bone mass assessment are discussed.

Absorptiometry, Photon↗
PubMed1993

Immunohistochemical demonstration of angiotensin II receptors in rat brain by use of an anti-idiotypic antibody.

In the present study we investigated the ability of an anti-idiotypic antibody which recognizes angiotensin II (AII) receptors to demonstrate the presence of such receptors under immunohistochemical conditions. The experiments revealed punctate immunoreactive granules on neurons of the nucleus supraopticus and of the nucleus paraventricularis of the hypothalamus. This localization of AII receptors is consistent with the findings obtained using other experimental approaches to the brain renin-angiotensin system. The conclusion of this study is that the applied anti-idiotypic antibody seems to be a reliable tool for mapping AII receptor distribution. The established experimental approaches to AII receptors are thus now supplemented with the possibility of immunohistochemical investigation. Moreover, the possible microscopic analysis of AII receptors on distinct cells will allow studies at an ultrastructural level.

Animals↗
PubMed1993

[Suspected adult-onset Still's disease: unexpected manifestation of leprosy].

A 23-year old male from Sri Lanka was admitted to hospital with symmetrical inflammatory peripheral polyarthritis, fever of 39 degrees C and poly-lymphadenopathy. At first we suspected adult onset Still's disease. The histological findings from axillary lymph node biopsy strongly suggested the diagnosis of leprosy, for which we had had little evidence thus far. Typical skin lesions were absent, skin smears were negative and neurological symptoms only became obvious much later when fever and arthritis had subsided under anti-inflammatory treatment. At this time a right ulnar palsy developed, with atrophy of the interosseous muscles and thickening of the ulnar nerves at both medial epicondyles. Fite-stains of a sural nerve biopsy confirmed the diagnosis when mycobacteria were detected. Leprosy displays a clinico-pathological spectrum caused by variations in host resistance. A widely accepted classification is the five group system of Ridley and Jopling. At one extreme of this spectrum are patients with lepromatous or low resistance leprosy with numerous bacilli, and at the other those with high resistance or tuberculous leprosy where few or no bacilli are found. The numerous bacilli in the sural nerve biopsy classified the disease as lepromatous in our case. Of the various manifestations of the lepra reaction occurring in lepromatous leprosy, one is acute arthritis, but a more common one is erythema nodosum leprosum. Our patient's clinical presentation was interpreted to be a rheumatic manifestation of a type-2 reaction. This form of immunological response in leprosy is an immune complex syndrome and may mimic different rheumatic diseases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

[Idiopathic spontaneous pneumoperitoneum. Case discussion based on two cases, assessment procedure and therapy and review of the literature].

Idiopathic spontaneous pneumoperitoneum is a rare condition we consider after exclusion of perforation of an intraabdominal viscus and other known causes of free intraperitoneal gas. We will report two cases of idiopathic spontaneous pneumoperitoneum seen during the year 1991 and discuss a rational way to get to the diagnosis. In the absence of peritoneal signs the rather unexpected amount of free intraperitoneal air is a constant finding. Reviewing the literature we found different opinions concerning the treatment of this condition. Regarding the benign character we emphasize a non-surgical management, given the careful exclusion of other, maybe fatal causes of pneumoperitoneum. Diagnostic peritoneal lavage may help to avoid unnecessary laparotomy.

Abortion, Induced↗
PubMed1993

HIV seroprevalence among patients attending a Milwaukee clinic for sexually transmitted diseases: findings from four annual surveys, 1988-1991.

Blinded HIV seroprevalence surveys were conducted annually from 1988 through 1991 among patients at a Milwaukee sexually transmitted disease (STD) clinic. Among 5,295 patients tested, 70 (1.3%) were HIV-1 Western blot positive. HIV seroprevalence rates were higher among male patients (1.7%) than among female patients (0.5%). HIV seroprevalence increased progressively with age and the number of prior STD episodes. During the four survey periods, HIV seroprevalence increased among teenage STD patients, patients who reported no prior STD, and patients without determined risk exposures. Selective voluntary HIV testing of patients who reported high risk exposures failed to detect 80% of all HIV seropositive patients. Because STD clinic patients are at high risk of HIV infection, HIV antibody testing, with appropriate referral of patients who test positive, and risk reduction education should be made routinely available to all STD patients with or without HIV-associated risk exposures.

Adolescent↗
PubMed1993

[Treatment of recurrent inguinal hernia by implantation of a pre-peritoneal prosthesis. Results of a prospective study].

44 patients with 47 recurrent inguinal hernias entered a prospective study. All patients were operatively managed by a standardized technique using a polypropylene (Prolene) mesh inserted through a pre-peritoneal approach. Operating in the pre-peritoneal space avoids dissection of the scared cord and the "inlay" prosthetic mesh safely creates a new "fascia transversalis" with a low rate of recurrences. All patients were personally controlled every 6 months with a follow-up time of 12 to 60 months (mean 20.2 months). The low postoperative morbidity included only one seroma, no infection and no testicular complications. We observed one recurrence occurring 6 months after surgery (2%). The described operative technique using an inlay patch is recommended as the therapy of choice in all recurrent groin hernias.

Adult↗
PubMed1992

[The entrapment syndrome of the popliteal artery: diagnosis, therapy, results].

The popliteal artery entrapment syndrome is caused by an anatomical anomaly in the popliteal fossa. Mostly the popliteal artery is compressed by a faulty insertion of the medial head of the gastrocnemius muscle. The main symptom is an intermittent claudication at an early age. We review our experience with four typical cases. All patients were examined because of a unilateral sudden claudication in the calf at ages between 23 and 43 years. In two patients we could find angiographically a typical stenosis, in two others a complete occlusion of the popliteal artery. Additionally a female patient showed a 6 x 8 cm poststenotic aneurysm in the popliteal fossa. Therapeutically we restored the flow of the artery on two patients by dividing the compressing gastrocnemius muscle. As a late complication two years after the first operation one of these patients had an occlusion of popliteal artery which was bypassed by a popliteo-crural vein graft. On two patients we primary inserted a vein graft. All patients were checked 6 months till 5 years after the first operation by duplex scanning, by measurement of pressure at the ankle and by pulse volume recording at the big toe. All our postoperative examinations demonstrate patency of the repairs and the patients have very few problems.

Adult↗
PubMed1989

Toxicosis in pigs fed selenium-accumulating Astragalus plant species or sodium selenate.

Three groups of 5 pigs each were fed a high selenium (Se) diet by mixing either Astragalus praelongus (31.6 ppm Se in feed), A bisulcatus (31.7 ppm Se in feed), or sodium selenate (26.6 ppm Se in feed) with commercial hog feed. Ten control pigs were fed only commercial hog chow containing trace selenium (0.44 ppm Se). Pigs were fed for 9 weeks and necropsied when they had ataxia or paralysis. Blood was collected for hematologic and serum biochemical determinations, and samples of various tissues were collected and fixed in neutral-buffered 10% formalin for histologic evaluation or frozen for determination of selenium concentration. All forms of selenium induced clinical signs of weight and hair loss, with cracked hooves and inflamed coronary bands developing in all Na2SeO4-fed pigs and 1 A praelongus-fed pig, but not in A bisulcatus-fed pigs. Serum calcium, phosphorus, and albumin concentrations were unchanged or significantly decreased from prefeeding values in groups fed selenium. Serum aspartate transaminase (AST) activities in Astragalus species-fed groups, and amylase activities and PCV in all groups of pigs fed selenium, were increased. Serum alkaline phosphatase and creatine kinase activities were significantly increased in the A praelongus-fed pigs and significantly decreased in Na2SeO4-fed pigs. Terminal tissue and body fluid selenium concentrations were determined in all groups of pigs fed selenium and compared with values in control pigs. Urine and bile concentrations were increased by the greatest factor (40 to 100x), with tissue concentrations of selenium increased by a lesser factor (6 to 17x).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Absence of infection with human immunodeficiency virus in Peruvian prostitutes.

We serologically tested 140 female prostitutes (mean age, 30 years) from the port city of Callao, Peru, for evidence of infection with human immunodeficiency virus (HIV), Chlamydia trachomatis, Treponema pallidum, herpes simplex viruses (HSV) I and II, and hepatitis B virus. The women had worked as prostitutes for an average of 5 years; one-fourth serviced foreign visitors exclusively, mainly sailors. Only 4 women used condoms, and only 1 woman gave a history of parenteral narcotic abuse, although 53% were regularly exposed to unsterile needles outside the medical setting for injections of vitamins, antibiotics, or steroids; another 29% are thought to probably use unsterile needles. None of the 140 prostitutes screened was seropositive for HIV, despite a very high prevalence of antibody to T. pallidum (24%), C. trachomatis (97%), HSV I and II (100%), and hepatitis B (51%); 5% were HbsAg positive. These data indicate that HIV has not yet been introduced into female prostitutes in the Peruvian port city. We believe that widespread use of unsterile needles in developing countries, such as Peru, represents a serious health threat and will amplify the spread of HIV, once introduced.

Adolescent↗
PubMed1985

Help yourself.

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Administrative Personnel↗