| 1. |
- Olsson, Marie, 1971, et al.
(författare)
-
Respiratory responses to intravenous infusion of sodium lactate in male and female Wistar rats.
- 2002
-
Ingår i: Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology. - 0893-133X. ; 27:1, s. 85-91
-
Tidskriftsartikel (refereegranskat)abstract
- In patients with panic disorder or premenstrual dysphoria, anxiety attacks can be triggered by intravenous administration of sodium lactate. Since respiratory symptoms, such as hyperventilation and shortness of breath, are characteristic features of spontaneous as well as lactate-induced panic, an involvement of central or peripheral chemoreceptors in this reaction has been suggested. In the present study, we examined to what extent intravenous infusion of sodium lactate influences respiratory parameters in freely moving male and female Wistar rats. Prompted by clinical reports suggesting that the susceptibility to spontaneous and lactate-induced anxiety may be influenced by the menstrual cycle, we also investigated if the effect of lactate on respiration in female rats is estrus cycle-dependent. Male and ovariectomized female rats exposed to sodium lactate displayed a larger increase in respiratory rate than rats given an infusion of saline. In intact female rats, the response to lactate infusion was significantly more pronounced in the diestrus phase than in the proestrus/estrus phase of the cycle. It is concluded that sodium lactate is a respiratory stimulant in rat, and that this effect is influenced by female sex steroids.
|
|
| 2. |
- Thylefors, Joakim, et al.
(författare)
-
Dark adaptation during systemic hypoxia induced by chronic respiratory insufficiency
- 2009
-
Ingår i: Investigative Ophthalmology & Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 1552-5783. ; 50:3, s. 12-1307
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To investigate dark adaptation during hypoxia in patients with chronic respiratory failure.METHODS: At three visits, dark adaptation was recorded by computerized dark adaptometry in 13 patients with chronic respiratory insufficiency treated by long-term oxygen therapy. At visits 1 and 3, the patients were administered their usual oxygen supplement. At visit 2, no oxygen was given. At each visit, an analysis of arterial blood gases measured pH, partial pressure of O(2) (Pao(2)), partial pressure of CO(2) (Paco(2)), base excess (BE), standard bicarbonate (HCO(3)), and arterial oxygen saturation. Pulse oximetry (POX) was also recorded.RESULTS: Significant differences were recorded between visits 1 and 2 and between visits 2 and 3 for Pao(2), arterial oxygen saturation, and POX; no differences were found for pH, Paco(2), BE, or HCO(3). No differences were seen between visits 1 and 3 for any of the laboratory parameters. All patients had normal and unchanged dark adaptation at the three visits.CONCLUSIONS: Hypoxia in chronic respiratory insufficiency was associated with normal dark adaptation, in contrast to hypoxia in healthy persons at high altitudes, which is known to produce impaired dark adaptation. The result may partly reflect the influence of Paco(2) on the lumen of choroidal and retinal vessels. At high altitudes, with hypocapnic vasoconstriction the oxygen supply to the retina is further compromised, resulting in reduced dark adaptation. The authors hypothesize that respiratory insufficiency with hypercapnia or normocapnia will have larger choroidal and retinal vessel lumens, added to by further dilation of retinal vessels during hypoxia. The tentative net effect would be preserved dark adaptation.
|
|
| 3. |
- Thylefors, Joakim, et al.
(författare)
-
Retinal detachment after cataract surgery : a population-based study
- 2022
-
Ingår i: Acta Ophthalmologica. - : Wiley. - 1755-3768 .- 1755-375X. ; 100:8, s. 1595-1599
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To analyse the risk of rhegmatogenous retinal detachment (RRD) after cataract surgery, and to identify possible risk factors.METHOD: Observational cohort study of patients undergoing cataract surgery in Region Skåne, southern Sweden, during 2015-2017 were retrieved from the Swedish National Cataract Register. These were then cross-referenced with cases of retinal detachment surgery performed at the Skåne University Hospital in Lund from 2015 to 2020. The main outcome was RRD after cataract surgery. The influence of sex, age, axial length of the eye, rupture of the posterior capsule, patient comorbidity and other cataract complications were analysed.RESULTS: Among the 58 624 cases of cataract surgery, a total of 298 RRDs (0.51%) were identified up to the end of 2020. The mean time from cataract surgery to RRD was 667 days. The mean age was 65.3 years, compared to 74 years in the control group. A strong correlation was found between RDD and age: <60 years, incidence = 0.50%; 60-75 years, incidence = 0.14%; and >75 years, incidence = 0.04%. The correlation with axial length was also very strong: mean value 23.73 mm in those without RRD, and 25.13 mm in those with RRD (p < 0.001). Sex was also strongly correlated to RDD; 68.8% of cases of RRD being men. Among men younger than 60 years of age, with an axial length ≥25 mm, 9.46% exhibited RRD within the follow-up period (mean 4.7 years). Rupture of the posterior capsule was found in 2.01% of RRD patients compared to 0.74% in the control group. Diabetes, glaucoma or pseudoexfoliation had no impact on the prevalence of RRD.CONCLUSIONS: The three main risk factors for RRD following cataract surgery were found to be sex, age and axial length. The highest incidence of RRD (9.46%) were identified among men younger than 60 years of age and an axial length ≥25 mm.
|
|
| 4. |
- Thylefors, Joakim, et al.
(författare)
-
The effect of axial length on pseudophakic retinal detachment
-
Ingår i: Acta Ophthalmologica. - 1755-375X.
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose The purpose of the study was to analyse the surgical management and outcome regarding axial length in the population affected by pseudophakic retinal detachment (PRD) 2015-2020. Method The patients included were from an observational cohort study of patients undergoing cataract surgery in the region of Skåne during 2015-2017. Data were retrieved from the Swedish National Cataract Register and cross-referenced with cases of PRD in the same region from 2015 to 2020. The surgical method used and findings at follow-up were recorded. The patients were stratified according to axial length (AL) to
|
|
| 5. |
- Thylefors, Joakim, et al.
(författare)
-
Two Eyes Are Better Than One-Binocular Summation of Dark Vision in Healthy Individuals and Patients with Chronic Respiratory Disease
- 2014
-
Ingår i: Neuro-Ophthalmology. - : Informa UK Limited. - 0165-8107 .- 1744-506X. ; 38:3, s. 113-121
-
Tidskriftsartikel (refereegranskat)abstract
- We compared monocular and binocular absolute thresholds of dark adaptation in two separate study populations. Eighteen healthy individuals (Group A) and 13 patients with chronic respiratory insufficiency (Group B) were examined three times each by computerised dark adaptometry with simultaneous but separate recordings from each eye and binocularly. The respiratory patients received oxygen supplement at visits 1 and 3. In Group A, at all three visits, binocular dark adaptation was significantly more sensitive (40.5%) than monocular dark adaptation with either eye. In Group B, at visits 1 and 3, binocular dark adaptation was also significantly more sensitive than monocular dark adaptation (40.5% higher than the right and 47% higher than the left eye). However, in Group B, at visit 2 without oxygen treatment, no significant differences were observed between monocular and binocular sensitivities. Binocular dark vision was superior to monocular dark vision in healthy individuals and in patients with respiratory insufficiency that were provided oxygen supplementation. Furthermore, deficit in oxygen seems to affect binocular summation, perhaps by impaired enhancement in the central nervous system.
|
|
| 6. |
- Thylefors, Joakim, et al.
(författare)
-
Visual Acuity Prior to Cataract Surgery and Risk of Retinal Detachment - A Population-Based Study
- 2023
-
Ingår i: Clinical Ophthalmology. - 1177-5467. ; 17, s. 1975-1980
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To analyze preoperative visual acuity before cataract surgery regarding the risk of rhegmatogenous retinal detachment (RRD) after cataract surgery.METHODS: The preoperative visual acuity in an observational cohort study of patients undergoing cataract surgery in Skåne, southern Sweden, during 2015-2017 was analyzed with data retrieved from the Swedish National Cataract Register. This was then cross-referenced with patients undergoing surgery for retinal detachment at the Skåne University Hospital in Lund from 2015 to 2020. The main outcome was the risk-benefit ratio of measuring preoperative visual acuity before cataract surgery and the risk of RRD.RESULTS: The mean visual acuity in the whole study group (N=58,624), expressed as LogMAR, was 0.40 ± 0.32 (SD). In the group with RRD (n=298), the mean visual acuity was 0.44 ± 0.36 (p=0.07). In the subgroups of RRD, those aged <60 years 0.49 ± 0.44 (p=0.07), aged <60 years and axial length (AL) >25 mm 0.42 ± 0.38 (p=0.68), and in those aged <60 years, AL >25 mm and male sex 0.44 ± 0.39 (p=0.53). However, there is considerable variations in visual acuity of the various groups and in the high-risk group with RRD aged <60 years with AL>25 mm, 15% had a visual acuity of 0.8 or better in the operated eye.CONCLUSION: There must be strong indications for performing cataract surgery in those with a high risk of retinal detachment, and the patient must be given adequate information on the risk of retinal detachment.
|
|
