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M Herman

Publications and source records attributed to M Herman.

At least 55 records · Page 3Linked to original sources
PubMed1999

Effects of antiprogestins on the rate of proliferation of breast cancer cells.

We have examined the influence of progestins (progesterone, R5020) and antiprogestins (RU486, ZK98299, Org 31710 and Org 31806) on the rate of proliferation of wild type T47D cells cultured in whole fetal bovine serum (FBS) or in single charcoal stripped fetal bovine serum (SSFBS). All of the progesterone antagonists RU486, ZK98299 and two novel antiprogestins Org 31710 and Org 31806 inhibited cell proliferation when cells were cultured in FBS. In contrast, all of the antiprogestins with the exception of ZK98299 enhanced cell growth when cells were cultured in SSFBS. This stimulatory effect of RU486 was observed only at a high concentration of the ligand (1 microM). The effect of R5020, however, was concentration independent. The number of cells in the presence of RU486 was approximately 600% followed by R5020 approximately 400% above control values after a 28 day culturing period. In contrast, when the cells were grown in the presence of medium containing non-stripped whole serum, RU486 inhibited the extent of cell proliferation by 45%. Estradiol (E2) stimulated the rate of proliferation in cells cultured in SSFBS. Similar to when cells were cultured in whole serum, the antiprogestins inhibited cell growth in E2-supplemented SSFBS. Detection of the growth enhancement effects of progesterone receptor (PR) ligands such as RU486 and R5020 on the cells grown in charcoal-stripped medium appear to require the removal of E2 by charcoal stripping of the serum.

Blood↗
PubMed1999

Current concepts in gastrointestinal photodynamic therapy.

OBJECTIVE: To review current concepts of photodynamic therapy (PDT) applied to the treatment of tumors of the gastrointestinal tract. SUMMARY BACKGROUND DATA: PDT initially involves the uptake or production of a photosensitive compound by tumor cells. Subsequent activation of the photoreactive compound by a specific wavelength of light results in cell death, either directly or as a result of vascular compromise and/or apoptosis. METHODS: The authors selectively review current concepts relating to photosensitization, photoactivation, time of PDT application, tissue selectivity, sites of photodynamic action, PDT effects on normal tissue, limitations of PDT, toxicity of photosensitizers, application of principles of PDT to tumor detection, and current applications of PDT to tumors of the gastrointestinal tract. RESULTS: PDT is clearly effective for small cancers, but it is not yet clear in which cases such treatment is more effective than other currently acceptable approaches. The major side effect of PDT is cutaneous photosensitization. The major limitation of PDT is depth of tumor kill. As data from current and future clinical trials become available, a clearer perspective of where PDT fits in the treatment of cancers will be gained. Many issues regarding pharmacokinetic data of photosensitizers, newer technology involved in light sources, optimal treatment regimens that take advantage of the pharmacophysiology of photoablation, and light dosimetry still require solution. One can foresee application of differing sensitizers and light sources depending on the specific clinical situation. As technologic advances occur, interstitial PDT may have significant application. CONCLUSIONS: PDT has a potentially important role either as a primary or adjuvant mode of treatment of tumors of the gastrointestinal tract.

Gastrointestinal Neoplasms↗
PubMed1999

Our experience with 3D CT.

The authors present the results of 9-year work with 3D CT in orthopaedics and musculoskeletal traumatology. In the years 1990-1998, the method was used in the examination of 59 patients (27 males, 20 females, and 12 children). The place of 3D CT in clarifying areas of complex musculoskeletal anatomy for operative treatment is discussed and presented as a contribution to the indication conference. According to the authors' experience, in many cases 3D CT increases the quality of diagnostics. Most of all, it helps the surgeon in operation planning. 3D reconstructions are particularly valuable in proximal humerus fractures, spine fractures and tumours, acetabulum fractures, as well as in conditions after hip dysplasia, LCPD and coxa vara adolescent.

Adult↗
PubMed1998

High-Resolution FTIR Spectroscopy Using a Jet: Sampling the Rovibrational Spectrum of 12CH4

We have recorded high-resolution absorption spectra of 12CH4 cooled in a jet, using a Fourier transform interferometer. The expected nuclear spin symmetry conservation in the jet is exhibited from data recorded around 3000 cm-1 showing the relative intensity of the lines starting from the J" = 2 para and ortho levels. Spectra recorded around 4300 cm-1 are used to validate existing rovibrational parameters. Spectra recorded around 6000 cm-1 allow new rovibrational assignments to be performed in the N = 4 polyad. In particular, lines in the nu1 + nu3 band are identified for the first time. Copyright 1998 Academic Press. Copyright 1998Academic Press

Journal Article↗
PubMed1998

High-Resolution Jet-Cooled Spectroscopy of SF6: The nu2 + nu6 Combination Band of 32SF6 and the nu3 Band of the Rare Isotopomers.

The Fourier transform infrared spectrum of SF6 was recorded in a supersonic expansion jet of an SF6/argon mixture. The SF6:Ar seeding ratio was 2:3. The instrumental bandwidth was 0.005 cm-1. A globar source and an MCT detector were used. A rotational temperature of approximately 30 K was achieved. The nu2 + nu6 combination band of 32SF6 was analyzed using a modified version of the spherical top data system (STDS) programs developed in Dijon. A very good fit was obtained for this band with an rms of 0.0036 cm-1. The effective Hamiltonian was developed up to fourth order for the nu2 + nu6 part, to second order for the nu2 and ground state parts, and to first order for the nu6 part. Five hundred twenty-one transitions were assigned, 40 of them reaching the F2u forbidden sublevel. The positions of the two F1u and F2u sublevels are found to be 991.276 and 989.487 cm-1, respectively. The nu3 band of the 33SF6 and 34SF6 isotopomers were also analyzed. Parameters and simulations are presented. A first detection of the nu3 Q branch of 36SF6 (0.02% natural abundance) is reported. Copyright 1998 Academic Press.

Journal Article↗
PubMed1998

Postoperative rhabdomyolysis in patients with end-stage renal failure.

Four patients with end-stage renal failure on intermittent hemodialysis in whom rhabdomyolysis developed after major surgery are described. This possibly underdiagnosed complication was manifested by extreme hyperphosphatemia, hypocalcemia, and elevated creatine phosphokinase levels. Serum myoglobin levels further supported the diagnosis. The metabolic abnormalities reached a peak on the fourth postoperative day. The possible precipitating factors included opiates used for anesthesia and postoperative pain control, anesthetic agents, and surgical position. The preferred treatment option is increasing dialysis to control hyperphosphatemia and hypocalcemia.

Adult↗
PubMed1998

A modified method of intracytoplasmic sperm injection without the use of polyvinylpyrrolidone.

In a controlled study we compared the outcome of intracytoplasmic sperm injection (ICSI) performed by two different methods. The oocytes from 20 patients were equally divided into two groups and injected either by conventional ICSI using polyvinylpyrrolidone (PVP) or by a modified PVP-free ICSI procedure. While in the conventional ICSI method the spermatozoon is aspirated into the injection pipette, in the modified ICSI procedure the spermatozoon is attached to the end of the narrow micropipette by aspirating its tail. The sperm head is never drawn into the pipette. Accordingly, even a fast-moving spermatozoon can be 'caught' easily. As a result of such an aspiration the spermatozoon loses its motility. Therefore, PVP is required neither to slow down the movement of the spermatozoon nor to facilitate the movement of the solution in the injection pipette. A total of 230 mature oocytes were injected by both methods and the results were analysed. No differences were observed in survival rate between the two ICSI procedures (89% and 91%, respectively). However, the proportion of normally fertilized oocytes was significantly higher after microfertilization by modified ICSI (74%) when compared with the outcome of the conventional ICSI method (62%). The frequency of abnormal fertilization was not influenced by the method of ICSI used. The cleavage rate and quality of resulting embryos were also comparable. In conclusion, we have demonstrated a modified ICSI method which does not require the use of PVP. When compared with the conventional ICSI procedure, even better fertilization rates can be achieved. The proposed ICSI modification may provide an alternative procedure for elimination of the potentially harmful effects which may be associated with conventional ICSI.

Cleavage Stage, Ovum↗
PubMed1998

The femoral artery-femoral vein polytetrafluoroethylene graft: a 14-year retrospective study.

BACKGROUND: The use of the femoral vessels for permanent haemodialysis access has been neglected during the last two decades. Since 1981 femoral artery-vein loop polytetrafluoroethylene grafts have been constructed in our chronic haemodialysis patients. This study examines results obtained in patients with this particular graft over the last 14 years. METHODS: This clinical study is retrospective in nature. Overall 35 patients, with 37 femoral grafts, are included. Inclusion and exclusion criteria for this type of graft are given and the surgical procedure detailed. RESULTS: Seven patients had femoral grafts used as primary dialysis access. Twenty-eight patients had femoral grafts used after multiple access failures. There was no perioperative mortality. Immediate thrombotic non-function of the graft occurred in three patients. In the long term no patient death was related to the femoral grafts. Twenty-seven (73%) grafts had no long-term complications. The leading cause for graft 'loss' was patient death; in the first year 10 grafts were lost, eight because of patient death. All eight patients died with functioning grafts. Median graft survival was 21 months in all patients and 28 months in non-diabetic patients. Twenty-seven (73%) grafts were patent at the end of the first year, 33% of grafts were still patent after 5 years. Worsening claudication occurred in four patients; one diabetic required foot amputation. Four patients had late graft thrombosis; only two patients had bacteraemia originating from the femoral graft. Urea reduction ratio greater than 60% was measured in 87.5% of patients. CONCLUSION: The femoral artery vein graft is a good primary and secondary haemodialysis access. Both infection and thrombosis rates are low and graft survival is comparable, if not superior to, that of upper-limb grafts. The graft is easy to cannulate, can be used early, is easily protected, and is cosmetically acceptable.

Adult↗
PubMed1998

The impact of antioxidant and splanchnic-directed therapy on persistent uncorrected gastric mucosal pH in the critically injured trauma patient.

BACKGROUND: Critically ill trauma patients with gastric intramucosal acidosis, as measured by gastric tonometry, have an increased incidence of multiple organ dysfunction syndrome despite supranormal O2 delivery. We altered our resuscitation protocol to maximize splanchnic blood flow and decrease oxygen-derived free radical damage. DESIGN: Prospective clinical trial with historical controls. METHODS: The protocol differed from control by including administration of folate, mannitol, and low-dose isoproterenol. All patients had gastric tonometers and pulmonary artery catheters. If the intramucosal pH (pHi) was less than 7.25, splanchnic-sparing inotropic and vasodilatory agents were used to optimize systemic cardiac output. Two groups of trauma patients with persistent intramucosal acidosis at 24 hours (pHi < 7.25) were compared: a control group (n = 7), and patients who received the splanchnic/antioxidant protocol (n = 13). RESULTS: The two groups were similar based on Acute Physiology and Chronic Health Evaluation II score, Injury Severity Score, age, cardiac index, oxygen delivery, and oxygen consumption. The "splanchnic therapy" group had fewer organ system failures as well as shortened length of intensive care unit and hospital stay. Three of 7 patients in the control group and 2 of 13 patients in the splanchnic therapy group had a final pHi < 7.25. CONCLUSION: Gastric tonometry-guided resuscitation and antioxidant/splanchnic therapy in critically ill trauma patients with persistent gastric mucosal acidosis may decrease multiple organ dysfunction syndrome.

APACHE↗
PubMed1998

CO2 asphyxia increases plasma norepinephrine in rats via sympathetic nerves.

The objective of this study was to determine whether the plasma norepinephrine (NE) increase in rats exposed to CO2 asphyxia was due to adrenal gland release or sympathetic nerve ending (SNS) release. Plasma NE was measured by high-performance liquid chromatography in hypertensive and normotensive rats using the following protocol: control session, CO2 exposure, N2 exposure, reserpine + CO2, and adrenalectomy + CO2. Four strains of male and female rats were used: spontaneously hypertensive rats, Wistar-Kyoto rats, and two congenic strains with different Y chromosomes. The same rats were used throughout the experiment (n = 80). Blood pressure measured by aortic telemetry increased approximately 50-60 mmHg in response to CO2 in all strains. CO2 increased NE 6-10x in all strains and both genders. N2 produced a significant increase in NE (73% of CO2 response). Reserpine significantly decreased (67%) plasma NE after CO2. Adrenalectomy did not significantly reduce the NE response to CO2. In conclusion, the increase in plasma NE after CO2 was associated with SNS release and not adrenal medullary release, was mainly due to hypoxia, and was not a specific response to CO2.

Adrenalectomy↗
PubMed1998

Paraganglioma of the cauda equina: case report and review of the MRI features.

We report a case of paraganglioma of the cauda equina and review the MRI features in 11 previously published cases with MRI description. On T1-weighted images, paraganglioma is isointense relative to spinal cord and shows moderate to intense enhancement after Gd-DTPA application, usually with heterogeneous texture. On T2-weighted images, different findings were found. MRI features do not allow to distinguish paraganglioma of the cauda equina from majority of other tumors in this region.

Cauda Equina↗
PubMed1997

Radiofrequency trigeminal rhizolysis for the treatment of trigeminal neuralgia secondary to brainstem infarction. Report of two cases.

Although percutaneous radiofrequency trigeminal rhizolysis (RFL) has been used to treat idiopathic trigeminal neuralgia thought secondary to multiple sclerosis, the use of RFL for trigeminal neuralgia caused by brainstem infarction has not been advocated. The authors report two patients with trigeminal neuralgia following pontine infarction in whom aggressive medical management failed, but who were successfully treated with RFL. Pain relief has persisted for the 3- and 6-year duration of follow-up examinations. Descending trigeminal reticular fibers may be affected by brainstem infarction and result in trigeminal neuralgia; thus, treatment by rhizotomy may be effective in decreasing the peripheral afferent input into the spinal trigeminal nucleus thus decreasing the pain. These two cases demonstrate the utility of RFL in the relief of ischemia-induced trigeminal neuralgia and lead the authors to suggest that its use be broadened to include this indication.

Journal Article↗
PubMed1997

High-Resolution Spectroscopic Investigation of nu16 in trans-1,2-Dichloroethane

We report on the first detailed rovibrational analysis in 1,2-dichloroethane. It concerns the a-type nu16 absorption band of gaseous trans-1,2-dichloroethane at 1232 cm-1, which we have recorded using a Fourier transform interferometer, under room temperature and jet-cooled experimental conditions. The rotational analysis of the almost diatomic-like prominent R and P structures in nu16 is performed for trans-1,2-12C2H435Cl2 and trans-1,2-12C2H435Cl37Cl. The nuclear spin statistics is discussed for various isotopomers and isomers of 1,2-dichloroethane. The complex absorption pattern observed at the band center is tentatively assigned in terms of overlapping Q branches, arising from fundamental bands involving different isotopomers in natural abundance (with 35Cl and 37Cl), and from related hot bands involving the three lowest vibrational modes in the molecule, nu6, nu10, and nu18. Copyright 1997 Academic Press. Copyright 1997Academic Press

Journal Article↗
PubMed1997

Characterization of ligand binding, DNA binding and phosphorylation of progesterone receptor by two novel progesterone receptor antagonist ligands.

In order to gain a better understanding of the distinctive mechanisms of the various types of antiprogestins, we have characterized in vitro ligand binding, specific DNA binding and phosphorylation of progesterone receptor (PR) from T47D cells after treatment of cells with progestins (progesterone, R5020) and antiprogestins (RU486, ZK98299, Org 31806 and Org 31710). Treatment of the cells with R5020 or PR antagonists, with the exception of ZK98299, resulted in a quantitative upshift of PR-A and PR-B indicative of ligand/DNA-induced phosphorylation of PR. Treatment of cells with RU486, Org 31710 or Org 31806, but not R5020 or ZK98299 resulted in detectable PR-progesterone response element complexes (PR-PREc) as assessed by gel mobility shift assay. Although treatment of cells with ZK98299, a type I PR antagonist, did not induce phosphorylation, the antiprogestins, Org 31806 and Org 31710, in a manner identical to RU486, did. Our data suggest that Org 31806 and Org 31710 affect properties of PR from T47D cells that are similar to RU486.

Binding, Competitive↗