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Biomedical subjects

G Richard

Publications and source records attributed to G Richard.

At least 19 recordsLinked to original sources
PubMed1992

[Success of retinal surgery comparing phakic and pseudophakic eyes with reference to preoperative findings and the kind of lens implant].

We analyzed retrospectively 597 eyes over a minimum follow-up of 6 months and compared the results of pseudophakic eyes with phakic eyes. The repair of pseudophakic retinal detachment is more difficult than the surgery in aphakic retinal detachment. Pseudophakic retinal detachment had a more advanced retinal detachment and PVR-stages at the time of diagnosis. Localisation of the tear was more complicated and the surgery was more invasive than in phakic eyes. In 61.2% the repair was for pseudophakic eyes with posterior chamber lens 78%, with anterior chamber lens 81.8% and for iris-fixated IOL's 75%. Compared to this, the anatomic reattachment rate in phakic eyes was 94.8%. The pseudophakic group had less favorable visual results.

Follow-Up Studies↗
PubMed1992

[Bacteriostatic activity and killing curves of eight antibiotics against seven strains of penicillin G-resistant pneumococci].

Increasing resistance to multiple antimicrobial agents including penicillins is a current problem with Streptococcus pneumoniae. Seven cases of severe infection due to penicillin G-resistant pneumococci were seen in two teaching hospitals in Paris (France) during the first half of 1991; six of the strains were recovered from pulmonary secretions (protected brush specimens) and one from cerebrospinal fluid (CSF). The bacteriostatic activity and killing curves of eight antimicrobials against these seven strains were studied. Antimicrobial agents tested included penicillin G (PEN), amoxicillin (AMX), cefotaxime (CTX), imipenem (IPM), rifampin (RIF), vancomycin (VAN), fosfomycin (FOS), and erythromycin (ERO). MICs were determined using the agar dilution method. Killing curves were obtained using a liquid medium inoculated with 10(5) to 10(6) CFU/ml and subjected to continuous agitation; survivors were counted at baseline and after 1, 3 and 5 hours incubation. MICs of each antimicrobial (mg/l) for the seven strains were in the following ranges: PEN: 0.5-2, AMX: 0.5-2; CTX: 0.125-1; IPM: 0.03-0.25; RIF: 0.12-0.25; VAN: 0.25-1; FOS: 16; ERO: 0.06 greater than 4. Overall, bactericidal activity was greatest with vancomycin, followed by imipenem, then amoxicillin. The cefotaxime-fosfomycin combination proved synergistic and exhibited bactericidal activity (2MIC + 2MIC) for three of the seven strains. This study demonstrated the value of the cefotaxime-fosfomycin combination. Both these antimicrobials seem appropriate for the treatment of meningitis caused by penicillin G-resistant pneumococci provided their dosage is adjusted to achieve adequate drug levels in the cerebrospinal fluid.

Amoxicillin↗
PubMed1991

Safety signal withdrawal: a behavioural paradigm sensitive to both "anxiolytic" and "anxiogenic" drugs under identical experimental conditions.

A new method involving the blockade of operant behaviour induced by the withdrawal of a conditioned signal for safety without presentation of a punishment signal has been developed for studying drugs with anxiolytic or anxiogenic properties. For this purpose, rats were trained under two alternating components of a multiple schedule of reinforcement FR8 (food)/FR1 (food) + RR 50% (shocks randomly delivered with 50 +/- 15% of the presses). The nonpunished and punished periods were signalled by one cue light above the right lever (safety signal) or the left lever (punishment signal), respectively. On the test session (safety signal withdrawal), the safety signal was turned off at the end of the first nonpunished period, but the punishment signal was not presented (every press was food rewarded and no shocks were delivered). During this period (4 min), rats exhibited a strong blockade of responding that lessened over time. This suppression seemed not to be caused by intervening events such as novelty, temporal conditioning, schedule of food delivery or ambiguity of the signal presented. The behavioural blockade induced by withdrawal of the safety signal was reduced by benzodiazepines: diazepam (0.5-4 mg/kg), chlordiazepoxide (4-8 mg/kg), nitrazepam (0.25-2 mg/kg), alprazolam (0.25-1 mg/kg), and partial agonists at benzodiazepine receptors: bretazenil (0.125-8 mg/kg) and ZK 91296 (32-64 mg/kg). Various 5-HT-related drugs also lessened the behavioural blockade:pCPA (3 x 150 mg/kg) and the 5-HT1A receptor agonists, buspirone (0.25-2 mg/kg), gepirone (0.25-1 mg/kg) but not 8-OH-DPAT. Compounds that may cause anxiety in humans further enhanced the blockade of lever pressing induced by the safety signal withdrawal at doses that did not modify baseline responding: d-amphetamine (0.125-0.5 mg/kg), caffeine (16 mg/kg) and picrotoxin (1 mg/kg). FG 7142 (8 mg/kg) and CGS 8216 (2-8 mg/kg) decreased responding during both components of the session. Therefore, the present paradigm seems sensitive to both "anxiolytic" and "anxiogenic" effects of drugs under identical procedural conditions.

Animals↗
PubMed1991

Acquired ocular toxoplasmosis. A fluorescein angiography study.

A 31-year-old man exhibited a bilateral deterioration of vision over the course of 1 week. The right fundus showed the picture of a central vein occlusion, and the left of a disseminated choroiditis. Indirect immunofluorescent testing indicated a titer of 1:2048 for toxoplasmosis. Fluorescein angiography revealed a hitherto unique picture of isolated choroidal occlusions but neither a central vein occlusion nor a disseminated choroiditis. Using only specific antitoxoplasmotic therapy, the patient regained full visual acuity on both sides. The original findings and the results of a 14-year follow-up are presented.

Adult↗
PubMed1991

Injector for highly viscous silicone oil.

A syringe device for the injection and evacuation of highly viscous silicone oil was developed. The problem of removing the air interfering with these manoeuvres was solved by providing special outlets in the plunger and handle of a conventional glass syringe. A slightly modified commercial motor perfusor was chosen to power this device, which has proved to be good and fail-safe in more than 100 cases.

Air↗
PubMed1991

Peritonitis in children on chronic peritoneal dialysis: analysis at 10 years.

Peritoneal dialysis is the major form of renal replacement therapy for children awaiting renal transplantation. Peritonitis is the major associated morbidity. We retrospectively identified the pathogens, co-morbid factors and outcome of peritonitis in children on peritoneal dialysis from 1980-1989. Seventy-three children, mean age 12.4 years, received 1,234 patient months of chronic peritoneal dialysis. Twenty-four patients (33%) remained peritonitis free until their dialysis catheters were removed after transplantation. Forty-nine children (67%) developed 219 episodes of peritonitis. Peritoneal fluid cultures were positive in 169 episodes (77%). Of the pathogens identified, 73% were gram positive cocci, 22% gram negative rods, 3% were fungus, and 2% other organisms. The incidence of peritonitis was one episode per 5.6 months. Over a 10 year period: 1) 67% of children on peritoneal dialysis developed peritonitis; 2) gram positive cocci accounted for most episodes; 3) the incidence in children was higher than that reported for adults; 4) there were no deaths attributable to peritonitis.

Child↗
PubMed1991

[Therapy of retinal detachment in Coats' disease].

Coats disease, an idiopathic condition of unknown etiology, includes teleangiectatic and aneurysmatic retinal vessels in association with massive subretinal exudation. Progression to retinal detachment caused by prolonged subretinal exudation means a poor prognosis. Retinal detachment surgery had always been controversial. Twelve patients (aged 7 to 48 years) with retinal detachment and Coats' disease were treated by various operations (cryotherapy, 4X; episcleral buckle, 2X; vitrectomy and gastamponade, 3X; vitrectomy and silicone-oiltamponade, 2X). One case (cryotherapy and cerclage) failed and went on to retinal detachment. In the other 11 cases the retinal was reattached successfully. However, peripheral, small areas remained detached, caused by persistent deposits of subretinal exudation. This means that the underlying Coats' disease is still active and must be treated by laser coagulation. It must also be monitored carefully, to keep an eye on the preretinal vitreous activities leading to detachment.

Adolescent↗
PubMed1991

Investigations on diathermy for anterior capsulotomy.

Diathermy is an approved instrument for intraocular surgery. The authors studied the effects and possible side effects of the first clinical application of a straight bipolar high-frequency probe used to cut the anterior capsule in extracapsular cataract exfraction (ECCE) with a continuous movement. In 25 patients with intumescent or mature cataractous lenses, on which capsulorhexis is difficult to perform, the anterior capsule was cut and a round capsulotomy of the desired diameter obtained. Simultaneously, intraocular temperature was measured for the first time in vivo inside the anterior chamber with a microtemperature probe during the operation. With the technique described, it reached a maximum of 33.4 degrees C (the maximum ranged from 32.8 degrees C-33.4 degrees C). There was no abnormal loss of corneal endothelial cells in the 12-month postoperative follow-up. In addition, electrolysis could not be verified experimentally.

Aged↗
PubMed1990

Multicentric adult secretory breast carcinoma: DNA flow cytometric findings, prognostic features, and review of the world literature.

A case of multicentric secretory breast carcinoma in a 39-year-old white female is described. Mammograms, DNA analysis, touch preparation cytology, and positive estrogen receptors are reported for the first time in this rare favorable mammary carcinoma. A review of the 33 reported cases with follow-up in adult females, including the present case, has revealed lymph node metastases in nine (27%), recurrence in four (12%), and distant metastases leading to death in two cases (6%). In patients treated with less than simple mastectomy there has been local recurrence in 4 (33%) of 12 cases and in three of the four cases (75%) greater than or equal to 2.0 cm. Increased size and lack of gross circumscription of the neoplasm and presentation in the adult age group appear to identify cases with an increased risk of disease progression. In patients over 20 years old, especially with neoplasms greater than 2 cm in diameter, modified radical mastectomy has to date achieved the most favorable outcome. Minimal experience (two cases) is available regarding treatment with limited surgery and radiation therapy, and there is no available data regarding possible benefit from adjuvant chemotherapy.

Adult↗
PubMed1990

[Genetics of Hailey-Hailey familial chronic benign pemphigus].

Starting from 12 index patients with familial benign chronic pemphigus from 11 kindreds, systematic kindred examinations were carried out with 182 relatives. 11 pedigrees were established. In this process 6 patients out of 3 kindreds were identified additionally. 10 genotypic carriers of the disease were found of 30 examined relatives by a newly developed UV-provocation test. An autosomal-dominant hereditary pattern was proven for sure and with high probability, respectively, in 10 out of 11 kindreds by formal genetic genealogy-examinations. There was an incomplete penetrance in 3 kindreds. A sex-determined heredity of disease can be excluded. There was no association between familial benign chronic pemphigus and HLA-A, B, C-system.

Female↗
PubMed1990

Membranoproliferative glomerulonephritis in a fifteen-month-old boy.

A 15-month-old boy presented with hypertension, edema, heavy proteinuria, gross hematuria and renal insufficiency. A renal biopsy was consistent with classical membranoproliferative glomerulonephritis type I. Although usually thought of as a disease in older children and young adults, membranoproliferative glomerulonephritis can occur as early as the second year of life.

Basement Membrane↗
PubMed1990

[Histology of UV-induced epidermis reactions. 1. A contribution to the differentiation of sunburn cells].

The UV-induced reaction of the epidermis is marked be extra- and intracellular edema and intraepidermal vesicles. Characteristical is the appearance of sunburn cells. In semithin section they can be differentiated in two cell types: "fried egg cells" prevail as early type in the exsudative phase (type I), "dark cells" as late type in the degenerative phase (type II) of the UV-reaction.

Biopsy↗
PubMed1990

[Modified technics for the examination of the central visual field].

The quantitative evaluation of small central and paracentral scotomas is a problem. Examination of the central visual field with an automatic or semiautomatic field analyzer can lead to a great number of false-positive results. Therefore, we have tried to develop two modifications of perimetric techniques: they allow continuous variation of the light intensity and quantitative recording of relative scotomas. For the investigation we used the well-known caro grid. With a new arrangement of the grid lines, it is possible to analyze nerve fibre scotomas. The results of the new perimetric techniques are presented.

Adult↗
PubMed1990

[Automatic compensation for the effect of eye movements in laser keratotomy].

In refractive laser surgery of the human cornea, especially in radial keratotomy, one major problem comes arises as a result of the patient's eye movements. If drugs to paralyze the muscles should be avoided, the laser beam must correspond with the eye movements. Here we present a closed loop tracking system, which uses an additional infrared optics to record the movements and a two-dimensional mechanically driven mirror to follow them. The functional principle and performance data are presented. The influence of different kinds of tracking on the therapy results are briefly discussed.

Eye Movements↗
PubMed1979

[Therapy of arterial vascular occlusions of retinal and optic nerve (author's transl)].

The authors report on 136 cases of arterial occlusion (80 patients suffering from occlusion of the retinal vessels and 56 patients with vascular occlusion in the optic nerve) who were treated with the vasoactive xanthic substance Pentoxifylline (Trental). A part from its positive effect on the vascular circulation, Trental also helps to improve microcirculation in the retinal and optic nerve tissue damaged by hypoxia. After a 2-week infusion therapy with additional digitalisation, treatment was continued for another 3-6 months with oral administration of Trental 400. In 50 cases therapy was combined with the systemic administration of corticosteroids. Under the mentioned therapy a definitely improved visual acuity (at least 3 lines on the eye charts) was achieved in 56% of the cases with occlusion of the retinal vessels and in 51% of the cases with vascular occlusion in the optic nerve, i.e., in 54% of the total number of patients. Whether or not the additional administration of corticosteroids helped to this effect was not proved.

Administration, Oral↗
PubMed1979

Suprapubic bladder needle aspiration in infants and children.

Suprapubic needle aspiration of the bladder represents an excellent alternative to urethral catheterization to document bladder bacteriuria. Specific indications include documentation of bacteriuria in infants, in uncircumcised male children, in myelodysplastic children, and in children with abnormal genitalia.

Adult↗
PubMed1978

Spectrum of multicystic renal dysplasia: diagnosis and management.

Multicystic renal dysplasia represents a spectrum of pathologic states, from unilateral multicystic kidney through segmental and focal multicystic dysplasia to bilateral multicystic kidney. Diagnosis can be established with low-risk procedures with reasonable accuracy. Treatment may be nonoperative in selected cases, but the physician must be responsible for long-term follow-up of the child until more is known about the natural history of this process.

Adolescent↗