Biomedical subjects

H Lönroth

Publications and source records attributed to H Lönroth.

At least 19 recordsLinked to original sources

PubMed2002

The transfer of basic skills learned in a laparoscopic simulator to the operating room.

BACKGROUND: The aim of the study was to evaluate whether basic surgical skills achieved by training in LapSim, a computerbased laparoscopic simulator, could be transferred to the operating room. METHODS: For this study, 24 medical students undergoing courses in surgery were randomly assigned to train with LapSim or to serve as control subjects. After they had undergone simulator training 2 h per week for 5 weeks, their basic skills in laparoscopic surgery were assessed in a porcine model. The time to perform each task was measured, and four senior surgeons independently graded the overall performance on a 9-step differential rating scale. RESULTS: The participants randomized to train with LapSim showed significantly better results for all tasks in both parts of the study than the untrained participants, according to the expert evaluation. Time consumption was accordingly lower in the training group in the control group. CONCLUSIONS: The results show that basic skills achieved by systematic training with a laparoscopic simulator such as LapSim can be transferred to the operating room.

Animals↗

PubMed2002

Randomized clinical study of the prevention of pulmonary complications after thoracoabdominal resection by two different breathing techniques.

BACKGROUND: Pulmonary complications are frequently seen after thoracoabdominal resection of the oesophagus. The aim of this study was to compare the effects of two different breathing exercise regimens applied in the immediate postoperative period on the risk of pulmonary insufficiency after thoracoabdominal resection. METHODS: Seventy patients undergoing thoracoabdominal resection for cancer of the oesophagus and cardia were randomized after operation to breathing exercises by inspiratory resistance-positive expiratory pressure (IR-PEP) (n = 36) or continuous positive airway pressure (CPAP) (n = 34). The study groups were well matched for all relevant clinical and demographic data. RESULTS: Respiratory function deteriorated significantly immediately after operation; the lowest values of forced vital capacity and peak expiratory flow were measured during the first postoperative day and oxygen saturation was lowest on days 4-6. Significantly fewer patients in the CPAP group required reintubation and prolonged artificial ventilation (P < 0.05). There were minor non-significant differences between the study groups with respect to respiratory and other postoperative variables, usually in favour of CPAP. CONCLUSION: Provision of CPAP in the immediate postoperative period decreased the risk of respiratory distress requiring reintubation and the need for artificial ventilation compared with breathing exercises by IR-PEP.

Cardia↗

PubMed2002

Helicobacter pylori infection inhibits antral mucosal nitric oxide production in humans.

BACKGROUND: Inducible NO synthase expression is upregulated in H. pylori-infected gastric mucosa, suggesting increased NO synthesis as part of a host defense reaction. This study investigates actual NO production in the human antrum in situ. METHODS: Gastroscopy with antral biopsy sampling and intragastric tonometric NO assessments were performed on H. pylori-positive and -negative volunteers. The antral mucosal specimens were analyzed with regard to inducible NO synthase (Western blotting) and the presence of the endogenous NO synthase inhibitor asymmetric dimethylarginine (ADMA) as well as L-arginine. RESULTS: Mucosal expression of inducible NO synthase was markedly increased in H. pylori infected subjects compared to noninfected ones. The ratio between the tissue contents of L-arginine and asymmetric dimethylarginine was considerably lower in the infected group. Antral output of NO was similar in the two groups during baseline conditions. Following intragastric L-arginine exposure. the antral NO production in controls was unaltered (from 442 ppb +/- 104 to 286 ppb +/- 94), whereas it increased (from 524 ppb +/- 162 to 1066 ppb +/- 274) in the infected individuals. CONCLUSIONS: The study confirms that NO synthase expression is increased in H. pylori-infected antral mucosa. However, NO synthesis is restricted owing to the presence of pathogen-induced competitive NO synthase inhibitors such as methylated arginines.

Adolescent↗

PubMed2001

[A case report: young man survived penetrating knife stabs to the heart and lung].

In Sweden, penetrating injuries to the lung and especially to the heart are fortunately rare. We hereby present a case-report on a young man who was stabbed in the right lung and heart. The paramedics arrived at the scene one minute after the alarm and instituted mechanical ventilation and fluid infusion. Ten minutes later the young man arrived at the emergency department. By then the patient was in deep shock without spontaneous breathing, was darkly cyanotic, showed indeterminately palpable pulses and non-reacting pupils. ECG-monitoring showed sinus-rhythm. Massive fluid infusion was initiated and the adolescent was immediately transported to the operating room. On the way to the operating room the patient's heart arrested. A lateral thoracotomy was performed to relieve the cardiac tamponade, and internal heart massage was initiated. Injuries to the lung and heart were reached through sternotomy. Thanks to prompt initial handling by the paramedics and emergency personnel, a trauma-trained senior surgeon and rather direct lines of communication at the small hospital, the young man could return to ordinary activities with neither physical nor neurological deficit.

Adolescent↗

PubMed2001

CD4+ and CD8+ T cell responses in Helicobacter pylori-infected individuals.

In order to characterize T cell responses in human Helicobacter pylori infection, we have examined proliferative responses and cytokine production by CD4+ and CD8+ T cells isolated from duodenal ulcer patients and asymptomatic H. pylori carriers, after activation with some H. pylori antigens that may be important in disease development. For control purposes, T cells from uninfected volunteers were also examined. The different H. pylori antigens induced only modest proliferative responses in circulating CD4+ and CD8+ T cells from both H. pylori-infected and uninfected individuals. However, circulating T cells from H. pylori-infected subjects produced larger amounts of interferon-gamma (IFN-gamma) in response to the Helicobacter antigens than did T cells from uninfected volunteers. Furthermore, CD8+ T cells produced larger amounts of IFN-gamma than did CD4+ T cells, on a per cell basis. Most IFN-gamma-producing cells from both infected and uninfected volunteers appeared to be naive T cells expressing CD45RA. Increased production of IL-4 and IL-5 was, on the other hand, only seen in a few instances after stimulation of isolated CD4+ and CD8+ T cells. Stimulation of freshly isolated gastric T cells with the different H. pylori antigens did not result in increased proliferation or cytokine production. In conclusion, our results show that several different purified H. pylori antigens induce production of IFN-gamma, preferentially by CD8+ cells. Therefore, they suggest that IFN-gamma-secreting CD8+ cells contribute significantly to the cytokine response induced by H. pylori infection.

Adult↗

PubMed2001

Induction of chemokine and cytokine responses by Helicobacter pylori in human stomach explants.

BACKGROUND: The cytokine response during the acute phase of Helicobacter pylori infection in humans has not been studied. The aim of this study was therefore to investigate the early cytokine responses against H. pylori using cultured human stomach explants as a model of acute infection. METHODS: Gastric corpus tissue obtained from 13 adult uninfected and 3 H. pylori-infected patients undergoing gastric surgery due to obesity was used for preparation of mucosal explants. The cultured explants were exposed to different H. pylori strains or antigens, that is, lipopolysaccharides (LPS), urease and heat-shock protein (Hsp) B. The responses of the CXC chemokines interleukin (IL)-8, growth-related oncogene alpha (GROalpha) and interferon-inducible protein (IP) 10 as well as the CC chemokine regulated on activation normal T-cell expressed and secreted (RANTES) were determined by ELISA. In addition, IL-4, IL-6, IL-10, IL-12, interferon gamma (IFNgamma), tumour necrosis factor alpha (TNFalpha) and granulocyte-macropage-colony stimulating factor (GM-CSF) were studied. RESULTS: In vitro H. pylori infection of the explants preferentially induced responses of the CXC chemokines GROalpha (P < 0.05) and IL-8 (P < 0.05), whereas the CC chemokine response (RANTES) was weak. In addition, the production of IL-6 was increased after H. pylori infection. Stimulation of the explants with different LPS preparations also induced strong GROalpha, IL-8 and IL-6 responses; the GROalpha responses being significantly higher after stimulation with rough than smooth H. pylori LPS (P < 0.05). CONCLUSIONS: GROalpha, IL-8 and IL-6 are increased early during acute H. pylori infection and may influence the development of gastric disease.

Adult↗

PubMed2001

Laparoscopic or open surgery for living donor nephrectomy.

BACKGROUND: The anterior extraperitoneal approach for living donor nephrectomy has been used in more than 700 living cases in the unit and proved to be safe for the donor. In 1998, laparoscopic nephrectomy was introduced as an option when technically feasible. We found it essential to investigate the consequences of the new technique. SUBJECTS AND METHODS: One hundred living donor kidney transplantations were performed from 1998 to June 2000, 45 with laparoscopic, 55 with open nephrectomy. The donors took part in a structured interview 4 weeks after the donation and their responses were categorized in three classes. RESULTS: In each group, one recipient had delayed initial function. The serum creatinine levels after 3 and 7 days or the GFR values after 6 months did not differ. One graft has been lost following laparoscopic nephrectomy and four after open surgery. For the laparoscopy donors, the median number of post-operative days in hospital was 5.0 days (range 2-9), vs 6.0 (4-8) after open surgery (NS). The requirement of opoid analgesics post-operatively was 5.0 doses (1-22) vs 6.0 (1-38) (P=0.02); and after 4 weeks, 23 of 45 laparoscopic donors were free of pain vs eight of 55 open nephrectomy donors (P=0.0004). Approximately one-third of all donors felt some restriction of physical activity and the majority complained of impaired physical energy. There were no differences between the groups. The duration of sick-leave after laparoscopic surgery was median 6 (2-19) weeks vs 7 (1-16) (NS). CONCLUSIONS: Laparoscopic nephrectomy is safe. Less post-operative pain is a definite advantage for the donor.

Adult↗

PubMed2001

Human gastric B cell responses can be induced by intestinal immunisation.

BACKGROUND: In a previous study, we found that oral vaccination induces strong B cell responses in the stomach of Helicobacter pylori infected but not of uninfected individuals. In this study, we have evaluated the possibility of inducing gastric immune responses in H pylori infected volunteers by intestinal and gastric immunisation. METHODS: H pylori infected subjects were given two doses of an inactivated cholera vaccine, either intestinally via an endoscope approximately 30 cm distal to the pylorus sphincter or intragastrically as small droplets applied directly onto the stomach mucosa. Uninfected individuals received the vaccine by standard oral procedure. Vaccine specific antibody secreting cells in antral and duodenal biopsies were detected by the enzyme linked immunospot assay technique before and seven days after the second immunisation. RESULTS: Intestinal immunisations resulted in induction of vaccine specific gastric IgA secreting cells in five of eight volunteers. This immunisation schedule also gave rise to specific duodenal antibody secreting cells in seven of eight individuals. Local gastric immunisation resulted in the induction of specific B cells in the gastric mucosa of four of eight volunteers. Gastric antigen application also resulted in B cell responses in the duodenum in all volunteers. Uninfected volunteers receiving the vaccine perorally responded in the duodenum but not in the stomach. CONCLUSIONS: H pylori infection increases the ability of the gastric mucosa to serve as an expression site for intestinally induced B cell responses. These findings are of importance when designing a therapeutic H pylori vaccine, and based on our results such a vaccine can be delivered along the whole upper gastrointestinal tract.

Administration, Oral↗

PubMed2001

Homing commitment of lymphocytes activated in the human gastric and intestinal mucosa.

BACKGROUND: Gastric infection with the human pathogen Helicobacter pylori results in a large accumulation of IgA and IgM secreting cells in the gastric mucosa. The molecular mechanisms resulting in B cell migration to the gastric mucosa in H pylori infection are however not known. AIMS: To examine expression of the mucosal homing receptor integrin alpha4beta7 and the homing receptor for secondary lymphoid tissues, L-selectin, on lymphocytes activated by gastric, intestinal, or systemic antigens. Furthermore, to examine gastric expression of the mucosal addressin cellular adhesion molecule 1 (MAdCAM-1), the endothelial counter-receptor to integrin alpha4beta7. SUBJECTS AND METHODS: H pylori infected individuals were immunised by either gastric (n=8) or intestinal (n=8) delivery of an inactivated cholera vaccine. The resulting circulating vaccine specific B cells were sorted according to alpha4beta7 and L-selectin expression and assayed for production of IgA and IgG using an enzyme linked immunospot assay. In addition, circulating CD4+ T cells from seven H pylori infected individuals were fractionated according to alpha4beta7 and L-selectin expression. The resulting T cell fractions were then assayed for specific proliferation against H pylori or the systemic antigen tetanus toxoid. Finally, gastric expression of MAdCAM-1 was determined by immunohistochemistry in H pylori infected (n=16) and uninfected (n=8) individuals. RESULTS: Virtually all B cells induced by both gastric and intestinal antigen delivery expressed alpha4beta7 whereas less then half coexpressed L-selectin. Furthermore, H pylori reactive T cells were mainly found in the alpha4beta7+L-selectin+ T cell fraction whereas tetanus specific T cells were largely alpha4beta7-L-selectin+. MAdCAM-1 was present in similar amounts in gastric mucosa from H pylori infected and uninfected individuals. CONCLUSIONS: B cells and T cells activated by antigens delivered to the gastric mucosa express the mucosal homing receptor integrin alpha4beta7, as do cells activated in the intestine. Together with the observation that gastric endothelial cells express MAdCAM-1, this may partly explain the homing of lymphocytes activated in the stomach or in the small intestine to the gastric mucosa.

ATPases Associated with Diverse Cellular Activitie↗

PubMed2001

Laparoscopic vertical banded gastroplasty--an effective long-term therapy for morbidly obese patients?

BACKGROUND: Vertical banded gastroplasty (VBG) has previously been documented as an effective treatment for morbid obesity. We have described a laparoscopic technique to perform this operation. Follow-up data are now presented. METHODS: A consecutive series of 139 morbidly obese patients were operated on with laparoscopic VBG. The patients were assessed with respect to peri- and postoperative morbidity, postoperative recovery and weight reduction up to 5 years thereafter. RESULTS: Conversions to an open operation (n = 6) and early reoperations (n = 3) occurred in the early part of the series. Late complications were observed in 8 patients. The average weight reduction after 1 year was 50% of excess body weight, which remained also after 2 years. The continued follow-up covering 3 to 5 years postoperatively revealed a moderate weight gain in about 20% of patients. CONCLUSION: VBG can be safely performed by use of the laparoscopic technique. The average weight reduction after 1 and 2 years was 50% of excess body weight, whereafter tendency to partial weight gain was noted, suggesting an outcome comparable to that documented after the open surgical approach.

Adult↗

PubMed2000

Development of a new method for the determination of immune responses in the human stomach.

The discovery of the gastric pathogen Helicobacter pylori has created a need for accurate methods to study immune responses locally in the human stomach. Therefore, we have developed a quick and easy method for extraction of antibodies from gastric biopsies using saponin and compared this method with the more laborious analysis of antibody-secreting cells (ASCs) from gastric biopsies. We have also analyzed the antibody content in gastric aspirates, saliva and plasma. There was a strong correlation between the total IgA levels in the biopsy extracts and the frequencies of IgA-secreting cells. In addition, the IgA and IgG levels against a H. pylori whole membrane preparation and purified urease in the biopsy extracts correlated well with the frequencies of specific IgA and IgG secreting cells. However, the antibody levels in gastric aspirates, saliva and plasma specimens did not correlate with the frequencies of corresponding ASC in the gastric biopsies. Thus, the saponin extraction method is suitable for monitoring local antibody responses in the stomach, while analyses of gastric aspirates, saliva or plasma are not appropriate for this purpose.

Adult↗

PubMed2000

Efficacy of, and quality of life after antireflux surgery.

A complete evaluation of reflux operations depends on measurements of preoperative and postoperative clinical symptoms such as dysphagia and heartburn, assessment of quality of life and objective measurements of 24-hour oesophageal pH monitoring and manometry. Quality of life can be measured with questionnaires such as the Gastrointestinal Symptom Rating Scale (GSRS), the Psychological General Wellbeing Index (PGWB) and the Reflux-related Visual Analogue Scale (RVAS). Failure of treatment is indicated by persistent symptoms such as heartburn, need for antisecretory medication, and new symptoms such as severe dysphagia. The advantages of laparoscopic operations are mainly a quick recovery and a good cosmetic results. Good short-term cure of symptoms is reported in 90%-97% of patients who have laparoscopic fundoplication. The long-term clinical outcome is equal to or better than that of open operations. Several clinical studies have shown that laparoscopic fundoplication is effective in improving symptom ratings and the quality of life.

Clinical Trials as Topic↗

PubMed1999

Chest physiotherapy does not improve the outcome in laparoscopic fundoplication and vertical-banded gastroplasty.

BACKGROUND: Chest physiotherapy is a common practice after open reflux and obesity surgery. It is now possible to perform fundoplication and vertical banded gastroplasty (VBG) by the laparoscopic technique. The aim of this study was to evaluate in a prospective, randomized, controlled trial whether chest physiotherapy affects the postoperative course. METHOD: A series of 40 patients underwent laparoscopic fundoplication; another 40 underwent laparoscopic VBG. Twenty patients in each series received prophylactic chest physiotherapy; the other 20 served as control patients and were not given any information or training. RESULTS: Postoperatively, all patients had a significant reduction in respiratory function, measured as oxygen saturation, forced vital capacity, and peak expiratory flow, but the differences between the groups within each series were not significant. Postoperatively, one patient in the VBG treatment group had hypoxemia (SaO2 <92%) versus two control patients. One control patient developed postoperative pneumonia. CONCLUSIONS: This study indicates that routine chest physiotherapy is not necessary in patients undergoing laparoscopic upper gastrointestinal surgery, such as fundoplication and VBG.

Adult↗

PubMed1999

Effects of breathing exercises on breathing patterns in obese and non-obese subjects.

Chest physiotherapy in connection with abdominal surgery includes different deep-breathing exercises to prevent post-operative pulmonary complications. The therapy is effective in preventing pulmonary complications, especially in high-risk patients such as obese persons. The mechanisms behind the effect is unclear, but part of the effect may be explained by the changes in breathing patterns. The aim of this study was therefore to describe and to analyse the breathing patterns in obese and non-obese subjects during three different breathing techniques frequently used in the treatment of post-operative patients. Twenty-one severely obese [body mass index (BMI) > 40] and 21 non-obese (BMI 19-25) subjects were studied. All persons denied having any lung disease and were non-smokers. The breathing techniques investigated were: deep breaths without any resistance (DB), positive expiratory pressure (PEP) with an airway resistance of approximately +15 cmH2O (1.5 kPa) during expiration, inspiratory resistance positive expiratory pressure (IR-PEP) with a pressure of approximately -10 cmH2O (-1.0 kPa) during inspiration. Expiratory resistance as for PEP. Volume against time was monitored while the subjects were sitting in a body plethysmograph. Variables for volume and flow during the breathing cycle were determined. Tidal volume and alveolar ventilation were highest during DB, and peak inspiratory volume was significantly higher than during PEP and IR-PEP in the group of obese subjects. The breathing cycles were prolonged in all techniques but were most prolonged in PEP and IR-PEP. The functional residual capacity (FRC) was significantly lower during DB than during PEP and IR-PEP in the group of obese subjects. FRC as determined within 2 min of finishing each breathing technique was identical to before the breathing manoeuvres.

Adult↗

PubMed1999

A novel tablet-based 13C urea breath test for Helicobacter pylori with enhanced performance during acid suppression therapy.

BACKGROUND: The urea breath test (UBT) can still be improved in terms of user-friendliness and accuracy during acid-suppression therapy. This study was designed to evaluate a novel, rapidly disintegrating 13C UBT tablet, which was supplemented with citric acid to facilitate diagnosis of Helicobacter pylori in the hypochlorhydric stomach. METHODS: The efficacy of a fasting 13C tablet-based UBT (TUBT) was compared with that of a standard 13C UBT (SUBT) during 40 min after dosing, and optimal sampling points were determined. The single-point TUBT was validated against a 'gold standard' (GS) including a TUBT, culture, histology, and a CLO test in 134 dyspeptic patients, and its optimal cut-off point was determined by means of a biometric method. In addition, 20 SUBT-positive patients were randomized to perform either the TUBT or the SUBT after 7 days of omeprazole therapy (20 mg twice daily). RESULTS: Compared with a SUBT, the TUBT gave a quicker and wider separation between positive and negative results and an earlier optimal sampling point (10 versus 40 min). At 10 min the TUBT correctly classified 40 of 42 GS-positive subjects (sensitivity, 95%) and all of 92 GS-negative patients (specificity, 100%), and the optimal cut-off point was 1.8 delta per mil. Furthermore, when optimal sampling points were used, the TUBT (t = 10 min) proved to be more accurate than the SUBT (t = 40 min) during omeprazole treatment, correctly identifying all of 10 and 3 of 9 H. pylori-infected patients, respectively. CONCLUSIONS: By supplying 13C urea and citric acid as a rapid-release tablet, it is possible to shorten the duration of the 13C UBT to 10 min, omit the test meal, and still maintain excellent accuracy, even during acid suppression therapy.

Anti-Ulcer Agents↗

PubMed1999

Role of local cytokines in increased gastric expression of the secretory component in Helicobacter pylori infection.

Using immunohistochemical staining, we examined the presence of secretory component (SC) on epithelial cells in gastric and duodenal biopsy specimens collected from Helicobacter pylori-infected individuals and healthy controls. Gastric epithelial cells from healthy volunteers expressed low, but detectable, levels of SC. In contrast, significantly higher level of expression of SC (P < 0.001) was observed on epithelial cells in the antra of H. pylori-infected individuals. The antral SC expression correlated with staining for gamma interferon of intraepithelial and lamina propria lymphocytes (r(s) = 0.76 and 0.69, respectively, P < 0.001) and correlated weakly with production of tumor necrosis factor alpha (r(s) = 0.43, P < 0.05), but it did not correlate at all with interleukin-4 production.

Adult↗

PubMed1998

Induction of B cell responses in the stomach of Helicobacter pylori- infected subjects after oral cholera vaccination.

We have evaluated the possibility of inducing antibody responses locally in the human stomach as a prerequisite for the development of a vaccine against Helicobacter pylori. Both H. pylori-infected and noninfected subjects were immunized with an oral B subunit whole cell (BS-WC) cholera vaccine, and total and vaccine-specific antibody-secreting cells (ASC) were determined by the enzyme-linked immunospot (ELISPOT) technique in cells isolated from the antrum and duodenum, respectively, before and after vaccination. Most of the subjects responded to the vaccination with high frequencies of vaccine-specific ASCs in the duodenum as well as high-serum antibody titers, and no significant differences were seen in the responses between H. pylori- infected and noninfected subjects. When studying the gastric mucosa, on the other hand, there were dramatic differences between the H. pylori-infected and the noninfected subjects. Thus, whereas none of the noninfected subjects responded to the immunization in antrum, most of the H. pylori-infected subjects had high frequencies of vaccine-specific ASCs in this location after vaccination. Furthermore, the H. pylori-infected subjects had strikingly higher (as a mean 80-fold) frequencies of total IgA-secreting cells in antrum than the noninfected subjects, whereas the frequencies of total IgA-secreting cells in the duodenum were comparable between the groups. In conclusion, these results demonstrate the possibility of inducing antibody responses locally in the gastric mucosa of H. pylori-infected individuals, a finding with obvious implications for the future development of a therapeutic vaccine against H. pylori.

Administration, Oral↗

PubMed1998

Other laparoscopic bariatric procedures.

Laparoscopic surgery is regarded as a major improvement reflected by a rapid recovery and low perioperative and postoperative morbidity. In obese patients the gains of this new technique may be affected by obesity-related problems, such as impaired respiratory function, high intraabdominal pressure, thick abdominal wall, and liver steatosis. This review describes the development of laparoscopic vertical banded gastroplasty (VBG) and gastric bypass procedures; and it addresses questions such as feasibility, comparability to open procedures, procedure-related problems, and recovery. The clinical outcome after laparoscopic VBG and gastric bypass is also updated. Up to May 1997 we have operated on 105 patients with laparoscopic VBG and another 26 completed laparoscopic gastric bypass procedures. The weight loss after both procedures are in accordance with the weight loss seen with open surgery. Procedure-related complications are described in detail in this paper. It is concluded that laparoscopic bariatric surgery will remain an area of importance for clinical practice, research, and development.

Adult↗