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Biomedical subjects

R Kessler

Publications and source records attributed to R Kessler.

At least 127 records · Page 7Linked to original sources
PubMed1995

Experimental delayed postischemic spinal cord hypoperfusion after aortic cross-clamping.

BACKGROUND: As in the brain, recent evidence has suggested a defect in the microcirculation during the reperfusion period after spinal cord ischemia. This investigation was undertaken in order to delineate blood flow dynamics in the postischemic spinal cord of the rat. METHODS: Male Sprague-Dawley rats underwent cross-clamping of the aorta and subclavian arteries (XC) for 11 minutes. Spinal cord blood flow (SCBF) was measured by autoradiography in the gray and white matter of cervical (Ce), thoracic (Th) and lumbar (Lu) regions during XC, 1 h, 6 h and 24 h (XC n = 8, 1 h n = 9, 6 h n = 9, and 24 h n = 11, groups) after XC. Control groups underwent surgical manipulations and SCBF measurement but no XC (Sham 1, n = 8), or clamping of the subclavian arteries only (Sham 2, n = 8). RESULTS: In Ce cord, there was no difference between SCBF of 1 h, 6 h, 24 h and Sham 1. In Th cord, SCBF was reduced during XC (P < 0.003 vs. Sham 2), 1 h, 6 h (P < 0.04 and P < 0.01 vs. Sham 1). In Lu cord, SCBF was not detectable in XC, and depressed in 1 h (P < 0.003) and 6 h (P < 0.003). There was no difference between 24 h and Sham 1 in Ce, Th, and Lu cords. CONCLUSIONS: The study demonstrated a period of delayed postischemic hypoperfusion in the white and gray matter of Th and Lu cord segments lasting 6 h after XC. The phenomenon may play an important role in the ultimate fate of neural elements with borderline viability after ischemic injury.

Animals↗
PubMed1995

Hemodilution is an effective treatment for reperfusion edema after lung transplantation.

A 38-year-old patient underwent left single-lung transplantation for end-stage histiocytosis with secondary pulmonary hypertension and polycythemia. Despite use of an optimal lung graft and a total ischemia limited to 250 minutes, major pulmonary edema developed postoperatively. Hemodilution resulted in a quick recovery of lung function. We speculate that blood hyperviscosity was a major factor of pulmonary edema in this patient.

Adult↗
PubMed1995

Antibacterial activities of cefprozil compared with those of 13 oral cephems and 3 macrolides.

Thirteen oral cephems (cefprozil, loracarbef, cefaclor, cefuroxime axetil, cefpodoxime proxetil, cefetamet pivoxil, cefixime, cefdinir, cefadroxil, cephradine, cephalexin, cefatrizine, and cefroxadine), the cephalosporin class representative cephalothin, cefazolin, and the macrolides erythromycin, clarithromycin, and azithromycin were compared for their antibacterial activities against 790 recent clinical isolates. These oral agents differed in their spectra and antibacterial potencies against community-acquired pathogens.

Administration, Oral↗
PubMed1995

Association of chronic obstructive pulmonary disease and sleep apnea syndrome.

The association of chronic obstructive pulmonary disease (COPD) and sleep apnea syndrome (SAS), which are both frequent diseases, is likely to occur in a number of patients. We have prospectively investigated a large series (n = 265) of patients who were selected solely on the basis of a confirmed diagnosis of SAS (apnea + hypopnea index > 20/hr). An obstructive spirographic pattern, defined by an FEV1/VC ratio < or = 60%, was observed in 30 of 265 patients (11%). These patients (subgroup "overlap") were older (58 +/- 9) versus 53 +/- 10 yr, p = 0.01) than the remainder of the study population, and all were male patients. Body mass index (BMI) was identical in overlap patients to that in the remainder. Vital capacity and FEV1 were lower, by definition, in the overlap group. PaO2 was lower (66 +/- 10 versus 74 +/- 10 mm Hg, p < 0.001) and PaCO2 higher (42 +/- 6 versus 38 +/- 4 mm Hg, p < 0.001) in the overlap group. Hypoxemia (Pao2, < or = 65 mm Hg) was observed in 17 of 30 overlap patients and in 54 of 235 of the remainder. Hypercapnia (Paco2 > or = 45 mm Hg) was observed in 8 of 30 overlap patients and in 19 of 235 of the remainder. The pulmonary artery mean pressure (PAP) was higher in overlap patients both at rest (20 +/- 6 versus 15 +/- 5 mm Hg, p < 0.01) and during steady-state exercise (37 +/- 12 versus 29 +/- 10 mm Hg, p = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Catheterization↗
PubMed1995

Prognostic factors in COPD patients receiving long-term oxygen therapy. Importance of pulmonary artery pressure.

Prognostic factors in COPD patients receiving long-term oxygen (LTO) therapy were recently analyzed, but very few studies considered the prognostic value of pulmonary artery pressure (PAP) in these patients. We investigated 84 patients who had undergone a right heart catheterization just before the onset of LTO. There were 75 men and 9 women, with a mean age of 63.0 +/- 9.9 (SD) years, at the onset of LTO. When PaO2 was persistently less than 55 mm Hg, LTO was initiated. This therapy was started in some patients with PaO2 in the range of 55 to 60 mm Hg if they had signs of cor pulmonale or a resting PAP of 25 mm Hg or greater at right heart catheterization. The daily duration of LTO was 16 h/d or more. Oxygen flow was adapted to achieve a PaO2 of 65 mm Hg or more. The patients were subdivided into subgroups according to the median value of age (cutoff value = 63 years); vital capacity (2,250 mL); FEV1 (800 mL); residual volume-total lung capacity ratio (58%); PaO2 value (52 mm Hg), PaCO2 level (45 mm Hg); and PAP (25 mm Hg). The cumulative 5-year survival rate was 48% for the group as a whole. Actuarial survival curves were plotted for the two subgroups of patients subdivided according to the initial median value of the variables just listed. There was no significant difference in survival rate between subgroups except when taking into account the level of PAP and age. In patients with an initial PAP of 25 mm Hg or less (n = 44), the 5-year survival was of 62.2 vs 36.3% in the remainder (n = 40) [p < 0.001]. We performed a multivariate analysis of survival using Cox's model of the proportional hazards regression including sex and the variables with the same categorization in the stepwise procedure: PAP and age were the only variables included in the final model. We conclude that the best prognostic factor in COPD patients receiving LTO is not the FEV1, nor the degree of hypoxemia or hypercapnia, but the level of PAP.

Actuarial Analysis↗
PubMed1995

[Results of repeated pulmonary resection in new homolateral neoplastic localization after conservative resection].

From 1978 through 1992, 93 patients with a previous lobectomy for bronchogenic cancer were referred for homolateral cancer recurrence. Forty-six patients were contraindicated for carcinologic reasons (30 stage IIIb and 16 stage IV). Forty-seven patients (50.5%) were resectable, but 17 did not undergo surgery for associated medical problems (n = 11) or refusal (n = 6). The remaining 30 patients form the population of the present study: 29 males and 1 female; mean age of 61 years (range 47-72). The previous cancer was stage I in 26 and stage II in 4. The mean interval between the 2 cancer diagnoses was 30 months (range 6-97). Three patients underwent an exploratory thoracotomy (10%): 2 had mediastinal involvement and 1 had pleural metastases. Twenty-two (73%) underwent a completion pneumonectomy, and 5 had miscellaneous conservative resections. There were 4 operative deaths (13%): one intraoperative bleeding, 1 postoperative bleeding, 1 pulmonary embolism, 1 pneumonia. Four patients had nonfatal surgical complications: 2 clottings (reexploration), 1 empyema (lavage) and 1 bronchopleural fistula (thoracoplasty). Resected patients were staged as follows: 13 stage I, 4 stage II, 10 stage III. Survival following resection including operative mortality at 3 an 5 years was estimated as 52.5% and 44% for the whole series (72% for stage I). We conclude that repeat surgery conveys an increased risk, but may achieve valuable long-term results.

Aged↗
PubMed1995

[Contribution of an induction treatment in the surgical treatment of locally advanced non-small-cell cancers].

From October 1988 to July 1990, 18 patients with marginally resectable non-small cell cancer (10 stage IIIa and 8 stage IIIb) were entered in a phase-II trial combining induction therapy with a subsequent thoracotomy. Induction therapy included 2 courses of chemotherapy (5-FU and cisplatinum) and radiotherapy (30 Gray in split course). Partial response was observed in 10 patients, and minimal response in 3. Thoracotomy disclosed unresectability in 3 patients. Fifteen complete resections consisted in 1 lobectomy and 14 pneumonectomies. There were no operative deaths (30 days). Postoperative recovery was uneventful in 3 patients with exploratory thoracotomy and in 1 patient with lobectomy. Following pneumonectomy, we observed 2 bronchopleural fistulae and 1 empyema. On pathology, 10 patients were stage IIIa, and 3 were stage I, whereas no residual tumor was found in 2 patients. During follow-up, local recurrence occurred in 2, and metastases in 8. On December 31st, 1993, 3 patients were alive at 44, 52, and 62 months respectively. Nine patients had died from cancer, and 3 from unrelated causes. Estimated survival was 66.7% at 1 year, 33.3% at 3 years, and 20% at 5 years. We conclude that induction therapy allowed satisfactory resection for marginally resectable tumors. Operative morbidity was increased in this group. However, the 5-year survival was similar to resectable stage IIIa cancer.

Adult↗
PubMed1994

Esophagopleural fistula: an early and long-term complication after pneumonectomy.

Over a 14-year period, we observed eight cases of esophagopleural fistula after pneumonectomy for cancer (n = 7) or infectious lung disease (n = 1). In 2 patients, the fistula was probably related to an intraoperative esophageal injury. Two others had mediastinal cancer recurrence, whereas a fistula developed in 4 without any malignancy. Patients presented with empyema, and a contrast swallow procedure disclosed an esophagopleural fistula. Two patients with recurrent cancer were managed conservatively with chest tube insertion and died within 3 months. A patient with chronic empyema had a delayed diagnosis of esophagopleural fistula 2 years after a presumed intraoperative injury; he was managed with thoracoplasty and feeding gastrostomy and died 12 months later. Five patients had an attempt at curative treatment. A single patient underwent thoracoplasty and bipolar exclusion of the esophagus and had secondary reconstruction with a coloplasty; he died with postoperative peritonitis. Four patients underwent thoracoplasty and muscle flap repair of the esophagus. There was 1 operative death from pulmonary embolism, whereas 3 patients recovered and are well with follow-up of 18 months, 2 years, and 5 years, respectively. We conclude that the prognosis of esophagopleural fistula is ominous when associated with cancer recurrence. A curative approach should combine direct repair of the esophagus with a muscle flap and eradication of the associated empyema with thoracoplasty. This aggressive treatment is addressed to debilitated patients and carries high rates of mortality and morbidity.

Aged↗
PubMed1994

Long-term experience with controlled expansion cylinders in the AMS 700CX inflatable penile prosthesis and comparison with earlier versions of the Scott inflatable penile prosthesis.

UNLABELLED: OBJECTIVEs. To determine complication and survival rates of the AMS 700CX penile prosthesis and to compare its reliability with earlier versions of the Scott inflatable penile prosthesis. METHODS: Retrospective chart review and telephone interviews were used. RESULTS: Actual 4-year survival of the AMS 700CX device was 85%, whereas earlier versions of the device had actual 4-year survival of 46% (p < 0.0001). The observed difference in prosthesis reliability could not be accounted for by differences in patient population, surgical technique, or incidence of infections. The most significant factor that contributed to improved prosthesis survival was the lack of cylinder complications (leaks and aneurysms). CONCLUSIONS: The controlled expansion cylinders of the AMS 700CX penile prosthesis are a significant advance in reliable, low-morbidity surgical therapy for impotence.

Actuarial Analysis↗
PubMed1994

NMDA receptor blockade and spinal cord ischemia due to aortic crossclamping in the rat model.

Recent brain research proposes that, during ischemia, synaptically released excitatory amino acid neurotransmitters accumulate at toxic concentrations with ensuing neuronal death. Their action is mediated by the receptor subtype N-methyl-D-aspartate (NMDA). The protective effect of NMDA receptor blockade with intrathecal MgSO4 and MK-801 was investigated during spinal cord ischemia induced by aortic occlusion of 12 minutes. Male Sprague-Dawley rats, 250-300g, underwent intrathecal administration of 20 microL of normal saline (SA n = 16), MgSO4 1M (MG n = 16), or MK-801, 25 mM solutions (MK n = 16) in a randomized order. After 2 hours, the animals underwent occlusion of the thoracic aorta and subclavian arteries for 12 min. An additional control group (CO n = 16) underwent occlusion for 12 minutes, without intrathecal injection. The animals were scored according to their functional performance (LS = lesion score) each day for four days by a blinded observer. Mean LS were calculated for each group at a given day. Treatment and control groups were not different at day 1 (P = 0.302). Group MG was improved from groups SA (P = < 0.0039) and CO (P = < 0.0048) at day 4. This study demonstrates that although intrathecal NMDA receptor blockade with MgSO4 or MK-801 does not prevent paraplegia due to spinal cord ischemia in the rat, it could however influence the rate of recovery after ischemic injury.

Animals↗
PubMed1994

Antitumoral potential of aerosolized interferon-gamma in mice bearing lung metastases.

Cytokines and immune cells are likely to be involved in the control of lung metastasis. We have therefore investigated the possibility of inhibiting lung metastases by the means of interferon-gamma (IFN-gamma) aerosolizations in a murine model of lung cancer. A Lewis lung carcinoma (3LL) was inoculated in the thigh of C57BL/6 mice. Randomized groups of 10 mice each were then treated by repeated aerosols of IFN-gamma (4,000 U/mouse) of aerosols of a Hanks' solution as controls. When the animals were killed at 18 days, the number of lung metastatic nodules was significantly reduced (by 50%; P < 0.01) after IFN-gamma aerosols, compared with controls. When the primary tumor was resected at 18 days and aerosols were continued, in the absence of local recurrence, mice treated by IFN-gamma aerosols survived longer than did controls (P < 0.05). In vitro, IFN-gamma exerted no direct antitumoral effect on 3LL cells in culture. Macrophages recovered from mice receiving IFN-gamma aerosols showed a higher antiproliferative effect on 3LL cells in vitro than did controls. Nevertheless, the higher antiproliferative effect of activated macrophages seems insufficient to explain the difference of survival that we observed between IFN-gamma-treated mice and controls.

Administration, Inhalation↗
PubMed1994

Medical treatment of pulmonary hypertension in chronic lung disease.

In chronic respiratory diseases, especially chronic obstructive pulmonary disease (COPD) pulmonary arterial hypertension is generally mild to moderate and the necessity for treating it can, therefore, be questioned. In fact, pulmonary hypertension, even when modest, may worsen markedly during acute episodes, exercise and sleep. These acute increases in mean pulmonary artery pressure (PAP) could contribute to the development of right heart failure. Therefore, the medical treatment of pulmonary hypertension is justified. There are, at the present time, no selective pulmonary vasodilators, with the exception of inhaled nitric oxide. Indeed, vasodilators appear less effective in COPD compared to primary pulmonary hypertension. Thus, there is, at present, no justification for the long-term use of vasodilators in COPD patients. Long-term oxygen therapy (LTOT) attenuates and sometimes reverses the progression of pulmonary hypertension, although the condition rarely returns to normal. We do not know whether the structural changes of the pulmonary vasculature in COPD patients are potentially reversible with LTOT. The longer the daily duration of LTOT the better are the haemodynamic results. At present, LTOT remains the best treatment for pulmonary hypertension in COPD patient. In the future, treatment of this condition in COPD patients could combine LTOT and specific vasodilators.

Humans↗
PubMed1994

[Diffuse nodular dissemination of thoracic actinomycosis].

Thoracic actinomycosis is a rare infection but sensitive to penicillin G which is the antibiotic of choice. We report a case of thoracic actinomycosis which was characterised by a relapse, probably linked to antibiotic resistance following treatment with Tetracycline. This relapse presented as diffuse nodular dissemination, of miliary type, of which there are only a few examples in the literature.

Actinomycosis↗
PubMed1994

[Cystic forms of primary bronchopulmonary cancers. Apropos of a case].

We report a case of primary broncho-pulmonary cancer presenting as a round, fine walled cyst. Based on the observations in this case, and from the data in the literature, we suggest the characteristics of the radiology and scanning which should enable the neoplastic aetiology to be suspected.

Cysts↗
PubMed1993

A twin study of recent life events and difficulties.

OBJECTIVES: To examine the role of genetic and familial-environmental factors in the origin of stressful life events. DESIGN: Self-report questionnaires describing stressful life events in the last year. PARTICIPANTS: Both members of 2315 twin paris ascertained from the population-based Virginia Twin Registry. RESULTS: Life events were modestly but significantly correlated in twin pairs, and correlations in monozygotic (MZ) twins consistently exceeded those in dizygotic (DZ) twins. For total life events, the best-fitting twin model indicated that familial-environmental and genetic factors each accounted for around 20% of the total variance. Individual life events could be best divided into "network events" (directly affecting individuals in the respondent's social-network) where twin resemblance was due solely to the familial environment, and "personal" events (directly affecting the response) where most twin resemblance was the result of genetic factors. CONCLUSIONS: While neither genes nor familial environment is likely to directly produce life events, personal and social factors that predispose to life events are substantially influenced by an individual's genetic and family background. These results, which suggest that stressful life events reflect more than random influences, may have important implications for our understanding of the relationship between stressful life events and psychopathology.

Adolescent↗
PubMed1993

Superiority of balloon occlusion arteriography to reactive hyperemic arteriography in visualization of distal lower limb vessels.

Balloon occlusion arteriography was performed in 38 lower limbs; reactive hyperemic arteriography was also performed in 16 of these limbs. To assess the safety and utility of this technique the balloon occlusion arteriograms of all 38 patients were reviewed retrospectively by a vascular surgeon and vascular radiologist who were unaware of the patient's identity and ultimate treatment. After the arteriograms were reviewed and the outflow vessels identified, a decision was made regarding operability and optimal recipient vessel for distal bypass. Twenty-two of the 38 patients underwent balloon occlusion arteriography only, and 21/22 (95.5%) of these patients only had studies deemed adequate for surgical planning. Twelve of the 16 (75%) patients underwent both reactive hyperemic arteriography and balloon occlusion arteriography; potential distal outflow vessels not seen on reactive hyperemic arteriograms were observed on balloon occlusion arteriograms. In only 4/16 (25%) patients the balloon occlusion arteriograms did not yield additional information. No complications were associated with this technique. Approximately 8.5 g of iodine per run is used for balloon occlusion arteriography compared with approximately 37 g of iodine per run for reactive hyperemic arteriography. Balloon occlusion arteriography is a safe and accurate adjunctive technique that can be used when identification of lower limb vessels is critical.

Adolescent↗
PubMed1993

A life-threatening tracheal localization of lymphoma in a patient with AIDS.

Lymphoma is a frequent complication of HIV infection, but we report a rare localization in the subglottic tracheal area. A case of tracheal stenosis due to lymphoma in an HIV-infected patient is presented. The main complaint was severe dyspnea. Chemotherapy was ineffective but radiotherapy improved the patient's condition and increased the caliber of the tracheal lumen.

Adult↗