Search PubMed⌕ Search

Biomedical subjects

J Hamacher

Publications and source records attributed to J Hamacher.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Functional results after bilateral thoracoscopic lung volume reduction surgery in emphysema].

We investigated functional results, complications and survival of patients undergoing bilateral video-assisted thoracoscopic (VAT) lung volume reduction surgery (VRS) for severe, diffuse pulmonary emphysema [FEV1 28 +/- 0.8 (% pred.), RV/TLC 0.65 +/- 0.01, 12' walking distance 499 +/- 21 (m)]. From January 1994 to March 1998, 106 of 286 candidates were operated, 85 patients (mean age 64, range 38-78 years, 30 females) fulfilled the study criteria and were included in the prospective study. Hyperinflation decreased to an RV/TLC ratio of 0.51 +/- 0.01 after 3 months and 0.55 +/- 0.02 after 24 months, FEV1 increased to 43 +/- 1.6 (% pred.) after 3 months and 35 +/- 2.3 (% pred.) after 24 months, and the 12' walking distance was 687 +/- 29 (m) 3 months postoperative and 626 +/- 44 (m) after 24 months.

Adult↗
PubMed1997

Pulmonary fibrosis with predominant CD8 lymphocytic alveolitis and anti-Jo-1 antibodies.

Interstitial lung disease (ILD) is a complication of polymyositis (PM) and dermatomyositis (DM). It often manifests itself in association with myositis-specific antisynthetase autoantibodies, among which anti-Jo-1 antibodies are the most commonly encountered. In contrast, ILD associated with anti-Jo-1 antibodies without muscle involvement is rare and not well characterized. We report four patients presenting with ILD associated with anti-Jo-1 antibodies. Histological findings of transbronchial biopsies disclosed a pattern consistent with nonspecific interstitial pneumonitis, a CD8+ lymphocytosis was found in bronchoalveolar lavage. Only one of these patients developed an "antisynthetase syndrome" with PM, after nearly 2 yrs of severe ILD. The clinical conditions of all four cases showed stabilization or improvement when cyclosporine was added to their immunosuppressive treatment. These cases confirm that a CD8+ lymphocytic interstitial lung disease may be the first, and sole manifestation of autoimmune disease associated with anti-Jo-1 antibodies. Furthermore, they suggest that this form of interstitial lung disease apparently has a poor response to steroids and cytotoxic drugs, but may respond to moderate doses of cyclosporine and azathioprine in addition to low doses of steroids.

Aged↗
PubMed1996

[Menstruation-associated (catamenial) pneumothorax and catamenial hemoptysis].

We report on 2 patients with catamenial pneumothorax and one patient with catamenial hemoptysis. The pathogenesis of these diseases is not clear, and intrathoracic endometriosis is often assumed. Catamenial pneumothorax is rare and differs from primary spontaneous pneumothorax in its prevalence in the fourth decade and in mainly multiparous women, its recurrent and almost exclusively right-sided occurrence within 72 hours of the beginning of menstruation, and the generally small size of the pneumothorax. About 5% of women under 50 presenting with primary pneumothorax have catamenial pneumothorax. Prevention of recurrence is difficult, as the recurrence rate is high, treatment duration is potentially long, and residual thoracic pain during menstruation is sometimes seen. The combination of medication (Gn-RH analogues, danazol, possibly hormonal contraceptive drugs or progestagens) with efficient pleurodesis (e.g. thoracoscopic talc application preferentially performed during menstruation) seems so far to be the most efficient, although no controlled studies have yet been performed. Catamenial hemoptysis is very rare and hormonal treatment alone is frequently successful in the long term. In the event of relapse, resection of the implicated endometriotic or angiomatous lesion localized by computed tomography can be performed.

Adult↗
PubMed1996

Serum bactericidal activities and comparative pharmacokinetics of meropenem and imipenem-cilastatin.

The pharmacokinetics and serum bactericidal activities (SBAs) of imipenem and meropenem were investigated in a randomized crossover study. Twelve healthy male volunteers received a constant 30-min infusion of either 1 g of imipenem plus 1 g of cilastatin or 1 g of meropenem. The concentrations of the drugs in serum and urine were determined by bioassay and high-pressure liquid chromatography. Pharmacokinetic parameters were based on an open two-compartment model and a noncompartmental technique. At the end of infusion, the mean concentrations of imipenem and meropenem measured in serum were 61.2 +/- 9.8 and 51.6 +/- 6.5 mg/liter, respectively; urinary recoveries were 48.6% +/- 8.2% and 60.0% +/- 6.5% of the dose in 12 h, respectively; and the areas under the concentration-time curve from time zero to infinity were 96.1 +/- 14.4 and 70.5 +/- 10.3 mg.h/liter, respectively (P < or = 0.02). Imipenem had a mean half-life of 66.7 +/- 10.4 min; that of meropenem was 64.4 +/- 6.9 min. The volumes of distribution at steady state of imipenem and meropenem were 15.3 +/- 3.3 and 18.6 +/- 3.0 liters/70 kg, respectively, and the mean renal clearances per 1.73 m2 were 85.6 +/- 17.6 and 144.6 +/- 26.0 ml/min, respectively. Both antibiotics were well tolerated in this single-dose administration study. The SBAs were measured by the microdilution method of Reller and Stratton (L. B. Reller and C. W. Stratton, J. Infect. Dis. 136:196-204, 1977) against 40 clinically isolated strains. Mean reciprocal bactericidal titers were measured 1 and 6 h after administration. After 1 and 6 h the median SBAs for imipenem and meropenem, were 409 and 34.9 and 97.9 and 5.8, respectively, against Staphylococcus aureus, 19.9 and 4.4 and 19.4 and 4.8, respectively, against Pseudomonas aeruginosa, 34.3 and 2.2 and 232 and 15.5, respectively, against Enterobacter cloacae, and 13.4 and 2.25 and 90.7 and 7.9, respectively, against Proteus mirabilis. Both drugs had rather short biological elimination half-lives and a predominantly renal route of elimination. Both carbapenems revealed high SBAs against clinically important pathogens at 1 h; meropenem had a higher SBA against E. cloacae and P. mirabilis, and the SBA of imipenem against S. aureus was greater than the SBA of meropenem.

Adult↗
PubMed1996

Osteoporosis in patients undergoing lung transplantation.

The occurrence of osteoporotic fractures may seriously compromise the quality of life of lung transplant recipients. However, at present, the true risk of osteoporosis in such patients is unknown. We therefore prospectively evaluated bone mass changes in patients undergoing pulmonary transplantation. Bone mineral density (BMD) of lumbar spine (LS), femoral neck (FN) and femoral shaft (FS), as well as whole body bone mineral content (WB-BMC) were measured in 21 consecutive candidates for lung transplantation (9 males and 12 females; mean+/-SD age 47+/-11 yrs). Twelve of the patients had their BMD remeasured within 6 months after surgery, and nine again after 1 year. Before transplantation, BMD at all sites as well as WB-BMC were significantly decreased as compared to the values in young healthy adults, FN being the most affected (FN -25+/-2%; LS, -12+/-4%; FS -9+/-2%, WB-BMC -15+/-4% (mean+/-SEM)). Seven out of 20 adult patients (35%) fulfilled World Health Organization (WHO) criteria for osteoporosis, i.e. BMD more than 2.5 SD below peak bone mass, whereas three had previously been diagnosed as having osteoporotic fractures of the spine or femoral neck. Within 6 months after transplantation, significant bone loss occurred, mostly at the LS level (-4.0+/-1.7%; p=0.04), despite calcium and vitamin D supplementation. Furthermore, two patients had new osteoporotic vertebral fractures. After 1 year, no further bone loss or new osteoporotic fractures were observed. In conclusion, evaluation of bone mass and prevention of bone loss should be considered early before lung transplantation. Further studies are needed to determine the efficacy of antiresorptive drugs on the prevention of accelerated bone loss and vertebral fractures after transplantation.

Adult↗
PubMed1995

Treatment of acute bacterial exacerbations of chronic obstructive pulmonary disease in hospitalised patients--a comparison of meropenem and imipenem/cilastatin. COPD Study Group.

Meropenem and imipenem/cilastatin were compared in an open, randomised prospective multicentre study in the treatment of acute exacerbations of severe chronic obstructive pulmonary disease in hospitalised patients. One-hundred-and-seventy-three patients were enrolled; 164 were evaluable for clinical efficacy and 98 for bacteriological efficacy, with 144 pathogens isolated. The predominant pathogens were Haemophilus influenzae (n = 30), Streptococcus pneumoniae (18), Staphylococcus aureus (12), Pseudomonas aeruginosa (11), Moraxella catarrhalis (8), other Gram-negative bacteria (Neisseria, Klebsiella, Proteus, and Enterobacter spp.) (53) and other Gram-positive bacteria (12). A single bacterial pathogen was identified in 61 patients, whereas two bacterial pathogens were isolated in 31 patients and three in six patients. The clinical response at the end of treatment was very high in both groups with a satisfactory outcome (cured or improved) in 97.6% of the meropenem patients and in 96.3% of the imipenem/cilastatin patients; at follow-up the rates were 89.1% and 89.8%, respectively. The bacterial success (eradication or presumed eradication) was 88.2% in the meropenem group and 89.4% in the comparator group. Nausea or vomiting were reported more frequently in patients treated with imipenem/cilastatin, whereas in the meropenem group an increase in aminotransferases was reported. One patient treated with imipenem/cilastatin was withdrawn from the study due to seizures. Meropenem and imipenem/cilastatin were highly effective for the treatment of severe bacterial exacerbations of chronic bronchitis but meropenem was better tolerated.

Bacterial Infections↗
PubMed1995

GRO alpha and interleukin-8 in Pneumocystis carinii or bacterial pneumonia and adult respiratory distress syndrome.

Polymorphonuclear leukocytes (PMN) are the predominant inflammatory cells recruited in acute lung injury. This study compares the concentration of interleukin-8 (IL-8) to those of GRO alpha, both of which are CXC chemokines, in bronchoalveolar lavage fluid (BALF) in three acute pathologic states: bacterial pneumonia (BPN); adult respiratory distress syndrome (ARDS); and Pneumocystis carinii pneumonia (PCP). Levels of both IL-8 and GRO alpha were below 5 pg/ml in 16 nonsmoking volunteers who served as controls. Despite more than twice as many neutrophils in the BALF of the BPN group (n = 12) than in the group with ARDS (n = 13), both groups had similar levels of IL-8, of 569 +/- 120 pg/ml and 507 +/- 96 pg/ml, respectively. The GRO alpha concentrations in the BPN and ARDS patients were respectively 3.3 and 3.4 times those of IL-8, reaching 1,870 +/- 314 pg/ml for the BPN and 1,699 +/- 377 for the ARDS patients. In the PCP group (n = 48, 45 human immunodeficiency virus [HIV]-positive, 3 HIV-negative), GRO alpha levels (897 +/- 172 pg/ml) were sevenfold higher than IL-8 levels (123 +/- 40 pg/ml). In all pathologic states there was a good correlation between GRO alpha and IL-8 (r = 0.53, p = 0.0001). GRO alpha or IL-8 both correlate with the absolute neutrophil number/ml when all groups were studied together (r = 0.52, p = 0.0001). Only in the PCP and ARDS groups did IL-8 correlate with the PMN number.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Opportunistic Infections↗
PubMed1995

Changing role of carbapenems in the treatment of lower respiratory tract infections.

The acquisition of antibiotic-resistance genes by virtually all major bacterial pathogens is currently a world-wide phenomenon. This problem is especially evident in nosocomial lower respiratory tract infections (LRTI). Carbapenems like imipenem and meropenem offer interesting antibacterial activities and beta-lactamase-stability, as well as adequate pharmacokinetic characteristics, to cover most of the pathogens involved in moderate to severe community-acquired and nosocomial LRTI. In contrast to imipenem, meropenem is not nephrotoxic and offers the advantage of greater stability against renal dehydropeptidase-I, so no concomitant application of an enzyme inhibitor is necessary. Meropenem can also be given by intravenous infusion or injection without the nausea and vomiting often associated with the administration of imipenem/cilastatin. Preliminary results with meropenem in LRTI show excellent cure rates and good tolerance for this new carbapenem.

Adolescent↗
PubMed1994

Adhesion molecules in lung diseases.

The human body possesses highly specialized cellular defense mechanisms that, when activated pathologically, can induce a number of immunologic disorders. For a normal cellular immune response, the following conditions must be fulfilled: (1) accumulation of white blood cells, (2) their diapedesis through the vessel walls of the inflammatory area affected by an injurious agent, and (3) normal cellular effector functions in the tissue. This cascade of inflammatory processes has recently been shown to be regulated by a group of molecules that are termed adhesion molecules and consist of three subfamilies: selectins, the immunoglobulin supergene family, and integrins. The cellular functions influenced by adhesion molecules include, among others, cytotoxic T-cell responses, CD4-dependent activation of B lymphocytes by T lymphocytes, activation of granulocytes and macrophages, phagocytosis of opsonized particles by monocytes, macrophages, and granulocytes, antigen-presenting function of macrophages, their antibody-dependent cytotoxicity, initiation of a respiratory burst by white blood cells, and activation of fibroblasts. Studies performed in recent years have shown that pathogenetically relevant changes in the expression and function of adhesion molecules are involved in a variety of pulmonary diseases. These changes include the accumulation and activation of alveolar macrophages in smokers, experimentally induced bronchial hyperreactivity in bronchial asthma, accumulation of eosinophils in allergic rhinitis, bleomycin-induced pulmonary fibrosis, binding of viruses and bacteria to respiratory mucosa, and various mechanisms of acute damage to pulmonary parenchyma. Though their role in tumor development is still unclear, adhesion molecules are obviously involved in determining the route and organotropism of metastases. Further studies of the function of adhesion molecules in pulmonary diseases will contribute to our understanding of the pathomechanisms of these diseases and, through the development of specific antibodies, may provide attractive new therapeutic approaches to problems for which treatment is not yet available.

Animals↗
PubMed1993

[Diagnosis and therapy of endobronchial and tracheal hamartomas].

Endobronchial hamartomas are a tenth as frequent as the usually asymptomatic intrapulmonary hamartomas. We report on 7 patients. 2 men and 3 women had an endobronchial hamartoma. In one patient multiple endobronchial hamartomas were found in the left upper lobe. In a 56-year-old patient with an 8-year history of shortness of breath, cough and several episodes of pneumonia and acute onset of respiratory failure, a tracheal hamartoma was diagnosed. Frequently, endobronchial hamartomas can be resected without loss of lung tissue. Laser resection is often possible and may be the treatment of choice in elderly or inoperable patients. Because of lower risk, laser resection is frequently preferred to conventional operative resection in patients with tracheal hamartomas.

Adult↗
PubMed1991

[Tuberculous pleuritis in pre-existent sarcoidosis].

The coexistence of the two granulomatous diseases sarcoidosis and tuberculosis in the same patient is rare and can raise diagnostic problems. We report a case of this kind in a 31-year-old man and discuss the diagnostic investigations, some of which can be misleading. In a patient with sarcoidosis and pleural effusion the possibility of tuberculosis must be ruled out, if necessary invasively.

Adult↗
PubMed1991

[Intraoperative monitoring with evoked potentials in spinal interventions].

This review article delineates the physiology and methodological principles of somatosensory (SEP) and motor evoked potentials (MEP), as well as our own results in 40 patients monitored during spinal surgery. In 29 patients an intraoperative SEP and in 15 patients a MEP monitoring was performed. Both modalities were applied in 4 patients. 19 patients had an intramedullary tumor, 15 patients had an intradural extramedullary tumor, 4 patients had an extradural mass lesion, and 2 patients had a spinal arteriovenous malformation. Technical problems with SEP monitoring occurred in 3 of 29 cases, problems with MEP monitoring occurred in 4 of 15 cases. Whereas anesthesia showed only little influence on SEP, an appropriate anesthesiological management was of major importance for MEP monitoring. Other factors, e.g. body temperature and blood pressure, also affected the evoked potentials. In all 35 patients in whom intraoperative SEP and/or MEP monitoring was successfully performed, evoked potentials showed a clear correlation with the initial postoperative neurological findings i.e. there were only cases of correct positive or correct negative monitoring. Transient evoked potential changes could always be attributed to surgical maneuvers. Our results show that intraoperative spinal cord monitoring with both SEP and MEP can supply helpful information on neural integrity. The choice of the evoked potential modality to be used and the choice of the sites of stimulation and recording depends on individual pathoanatomical findings and on the operative procedure required. Intraoperative evoked potential monitoring is indispensable during high risk spinal surgery such as surgery for intramedullary tumor or for mass lesions above C5.

Afferent Pathways↗
PubMed1978

[Methods for simultaneous recording of pharmacodynamic and toxic effects on interior sensitive receptors, respiration and cardiac-circulatory system of guinea pigs (author's transl)].

A method for simultaneous, continuous registration of pharmacodynamic and toxic effects, resp., on pulmonary-stretch receptors, on respiration and on hemodynamics in guinea pigs is described. The following parameters are recorded synchronously by a multi-track recorder: 1. The afferences in the cervical n. vagus; its electrical integration is employed for measuring the total intensity and the ex- and the inhalation intensity, resp., of the afferences; 2. the pneumatogram for measuring the maximum velocity of air flow, duration of the breath phase and parts thereof (in-, and exhalation and postexpiratory pause), and the respiration rate; 3. the diastolic and systolic blood pressure during in- and exhalation and postexpiratory pause; 4. the electrocardiogram (ECG). The normal distribution of the initial values is examined and discussed. Further the initial values measured in three series of experiments are discussed and compared: mono-vagotomy/spontaneous respiration, bivagotomy/spontaneous respiration and artificial respiration/monovagotomy. The results are compared with some experimental and clinical findings from literature.

Animals↗