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Biomedical subjects

R Kohn

Publications and source records attributed to R Kohn.

At least 73 records · Page 4Linked to original sources
PubMed1985

[The distribution of free and esterified carboxyl groups within the pectin molecule after the action of pectin esterase from Aspergillus niger and oranges].

By reaction of pectin esterase (PE) from Aspergillus niger and oranges as well as lye, with 95% esterified citrus and apple pectin we prepared series of preparations with degrees of esterification between 35 and 77%. In these partial deesterified pectins the form of distribution of the free and esterified carboxyl groups has been determined from the activity coefficient gamma Ca2+ of the calcium counterions in the solutions of the corresponding calcium pectinates, from the electrostatic free enthalpy delta (Gel/N)KCa of the ion exchange Ca2+----2K+ in these systems as well as from the relative activity of the polygalacturonase reacting with sodium pectinate. The PE from A niger hydrolyzes the esterified carboxyl groups more or less randomly, in a manner similar to the effect of lye on pectin. On the other hand PE from oranges brings about block-like groupings of free carboxyl groups in the pectin molecule. The study revealed different reaction mechanisms of the pectin deesterification by pectin esterases from Aspergillus species and higher plants.

Aspergillus niger↗
PubMed1985

Management of limited rhino-orbital mucormycosis without exenteration.

Eight cases of rhino-orbital mucormycosis managed successfully without exenteration were reviewed. The favorable outcome was attributable to early diagnosis and management of focal areas of fungus infection. Treatment included: correction of diabetic ketoacidosis or other concomitant metabolic derangement; wide local excision and debridement of all involved and devitalized oral, nasal, sinus, and orbital tissue, while establishing adequate sinus and orbital drainage; daily irrigation and packing of the involved orbital and paranasal areas with amphotericin B; and intravenous amphotericin B. This represents the largest reported series of rhino-orbital mucormycosis survivors without mutilating surgery and with unaltered visual acuity.

Adult↗
PubMed1983

Treatment of eyelid retraction with two pedicle tarsal rotation flaps.

Five patients with eyelid retraction (seven eyelids, four upper and three lower eyelids) associated with blepharoptosis surgery, Graves' disease, and vertical extraocular muscle surgery were effectively treated with a new technique involving recessing the respective eyelid retractor beyond the tarsal border. Direct attachment of the levator aponeurosis or the inferior aponeurosis (capsulopalpebral head of the inferior rectus muscle) into the tarsus was maintained through an extended framework created by two pedicle tarsal rotation flaps. This anatomic retention of the tarsal-retractor junction enhanced transfer of muscle contracture into eyelid movement. The only adverse effect was a 4-mm gap in the eyelashes of one patient.

Adolescent↗
PubMed1981

Rapid recurrence of papillary squamous cell carcinoma of the canaliculus.

We treated a 76-year-old man who had an epithelial carcinoma that involved the canaliculus and extended into the lacrimal sac. Despite what appeared to be adequate resection (the surgical margins were completely free of tumor on both frozen and paraffin section), the tumor recurred less than one month later. The patient underwent wide local incision, including en bloc removal of the medial third of both eyelids and inner canthi, canaliculi, lacrimal sac, and nasolacrimal duct, and resection of the anterior lacrimal crest, lacrimal bone, anterior portion of the ethmoid bone, anterior medial wall of the maxilla, and subjacent periosteum and mucous membranes. Sixteen months later, the tumor has not recurred. This infiltrating papillary squamous cell carcinoma histologically demonstrated the most rapid and destructive recurrence of any such tumor originating in the lacrimal system.

Aged↗
PubMed1980

Mixed cryoglobulinemia: clinical aspects and long-term follow-up of 40 patients.

The clinical course of 40 patients with significant quantities of mixed cryoglobulins, but without lymphoproliferative, collagen-vascular or chronic infectious diseases, is presented. These cases comprise 51.3 percent of all mixed and 31.7 percent of all types of cryoglobulins evaluated by us over the period 1960--1978. A characteristic clinical syndrome, consisting of recurrent palpable purpura (100 percent), polyarthralgias (72.5 percent) and renal disease (55 percent), was seen. Biopsy specimens of skin lesions showed cutaneous vasculitis, and half had immune reactants in vessel walls. Seventy percent of patients had evidence of hepatic dysfunction, often subclinical, and more than 60 percent of those tested had serologic evidence of prior infection with hepatitis B virus. Hepatic lesions ranged from minimal triaditis to chronic active hepatitis and/or cirrhosis. All 22 patients in whom clinical renal disease developed had significant proteinuria; 63.6 percent had diastolic hypertension, 77.3 percent edema, 45.5 percent renal failure and 22.7 percent were nephrotic. Glomerular disease associated with deposition of immunoglobulin G, immunoglobulin M and complement, often with coexistent renal arteritis, was confirmed pathologically in 15 cases. All cryoglobulins had rheumatoid factor activity and consisted of IgM and polyclonal IgG; five also contained IgA. Thirteen had a monoclonal IgM kappa component. Serum protein electrophoresis was unremarkable or showed diffuse hyperglobulinemia. Striking depression of early complement components was noted but did not correlate well with the cryoprotein concentration, renal involvement or clinical course. Follow-up for periods up to 21 years from onset of symptoms revealed that renal involvement has a deleterious effect on prognosis. Postmorten examinations of nine patients demonstrated widespread vasculitis in addition to renal involvement. Preterminal infection was found in eight.

Cryoglobulins↗
PubMed1979

Dacron patch enlargement of anterior wall of left ventricle after aneurysmectomy with concomitant infarctectomy.

The basis for left ventricular aneurysmectomy with cardiopulmonary bypass was established 20 years ago. There is a higher risk in patients who undergo operation within 2 months of myocardial infarction. In these patients there may be no clear demarcation between devitalized tissue and residual healthy myocardium. A case is reported in which anterolateral aneurysmectomy with concomitant infarctectomy so compromised left ventricular size that the anterolateral wall of the left ventricle had to be reconstructed with a Dacron patch graft.

Adult↗
PubMed1979

Mechanical ectropion repair using tarsal rotation sutures.

Chronic mechanical ectropion may persist despite elimination of its causal factors. Four such cases are presented in which traditional surgical management was not appropriate. Instead, tarsal rotation sutures were applied, eliminating the ectropion and deepening the inferior fornix in each case. This technique is presented in detail, along with a discussion of its mechanical principle which establishes the infraorbital rim as the center of rotation of the eyelid, anchoring the sutures and placing an inward torque on the tarsal plate.

Adult↗
PubMed1976

Lacrimal obstruction after migration of orbital floor implant.

A 7-year-old girl developed epiphora, recurrent purulent conjunctivitis, and dacryocystitis 32 months after the repair of a traumatic orbital floor fracture. Dacryocystography and surgical exploration revealed that migration of the orbital floor implant had caused obstruction of the nasolacrimal duct at the sac. Migration of the implant was probably due to a failure to anchor the implant properly to bone.

Bone Plates↗
PubMed1976

Abnormal lung elasticity in juvenile diabetes mellitus.

Static lung pressure-volume curves, lung volumes, spirometry, diffusing capacity for CO, and airway and total pulmonary resistance were determined in 11 young men with juvenile-onset diabetes mellitus who were not cigarette smokers. Twelve nonsmoking men of similar age without diabetes served as control subjects. Elastic recoil at low lung volumes was significantly less in the diabetics than in the control group. Total lung capacity was also decreased in the diabetics. There were no significant differences between the 2 groups in the other parameters of pulmonary function measured. It is postulated that the abnormalities in lung elastic behavior are manifestations of the widespread elastin and collagen abnormalities that have been demonstrated in diabetes and are, in some respects, similar to those that occur during normal aging. Loss of elastic recoil at low lung volumes may cause more significant decreases in flows and gas transport as the juvenile diabetics age.

Adult↗
PubMed1975

Lipidosis with a predominant storage of phosphoglycerides (phospholipidosis type II--Baar, Wiedemann).

A case of a 27 month old girl suffering from a rare form of lipidosis is described. Clinical symtoms consisted of a moderate hepatosplenomegaly and a progressive psychomotor retardation. Bioptical examination of the liver, appendix and skin revealed a pronounced lipid storage in histiocytes, hepatocytes, vascular endothelium and in peripheral nervous system. Histochemically, a generalized storage of phosphoglycerides and cholesterol was found. It was accompanied with a moderate amount of sphingomyelin and a variable amount of glycolipids (predominantly glycosphingolipids), the latter being stored mainly in the peripheral nervous system and in the vascular endothelium. Chromatographically, an increased concentration of lysobisphosphatidic acid and cholesterol could be detected. The ultrastructure of storage cytosomes was rather pleomorphic often with concentrically lamellar appearance. Further details of the investigation are described and the relation of this case to those described by Baar and Hickmans (1956) and Wiedemann et al. (1972) is stressed. Due to a strong evidence that this group of diseases represents a new type of phospholipid storage disease the name "Phospholipidosis Type II" (Baar-Wiedemann) or "Phosphoglyceridosis" is proposed, whereas "Phospholipidosis Type I" or "Sphingomyelinosis" should be reserved for the classical Niemann-Pick complex.

Appendix↗
PubMed1975

The management of benign renal tumors of infancy. Case report of a congenital mesoblastic nephroma (leiomyomatous hamartoma).

A case of a benign renal tumor found in an infant of 11/2 months is reported. Its clinical, radiological and operative findings were similar to those described previously as Wilms' tumors. Only pathological examination revealed its benignancy. In view of the occurrence of benign congenital mesoblastic nephroma which is evidently not rare in infancy, and because of the side effects of adjuvant cytotoxic and X-ray therapy, the authors feel that the immediate therapeutic approach to a solid intrarenal tumor in infancy should be surgical only. Further therapy should depend on pathological findings.

Humans↗