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H Reuveni

Publications and source records attributed to H Reuveni.

29 records · Page 2Linked to original sources

The intermediate care unit as a cost-effective option for the treatment of medical patients in critical condition.

Since the limited accessibility of general intensive care units creates a situation in which medical patients in critical condition continue to be cared for in the regular wards, we conducted a retrospective cohort study to assess the treatment outcomes in such patients referred to the medical intermediate care unit (MICU). At the Soroka Medical Center, a facility with 810 beds, of which 170 beds are in medical wards, including an 8-bed intensive cardiac care unit and a 5-bed general intensive care unit, 119 patients were referred to the MICU, directly from the emergency room or from medical wards, during the first half of 1994. Eighty percent of the patients were admitted to the MICU directly from the emergency room. The mean disease severity, as measured by the APACHE II score, was 12.9, and the mean intensity of care for these patients, as measured by the TISS scale, was 12.6. Twenty-one of the 119 patients died during hospitalization (17.6%). This mortality rate conformed to the mortality risk of 15.5%, which was calculated using prognostic formulae. The ratio of nursing staff to patient in the MICU was approximately 1:3, compared to 2:3 in the general intensive care unit and 1:12 in the wards. The mean cost of one day of hospitalization in the MICU was one-third that in the general intensive care unit and double the cost in a ward. Medical patients in critical condition can be treated in an MICU, with a savings in expenses and without impairing the patient's chances for survival.

APACHE↗

Thymidine salvage changes with differentiation in human keratinocytes in vitro.

We compared the capacity of proliferating and differentiating keratinocytes to salvage and catabolize extracellular thymidine. Both populations of cells catabolized thymidine to thymine and possessed thymidine phosphorylase activity. As keratinocytes differentiate, thymidine phosphorylase activity ultimately increased twofold. In contrast, proliferating and differentiating keratinocytes differed markedly in their capacity to salvage extracellular thymidine. Proliferating keratinocytes readily salvaged extracellular thymidine to form nucleotides, whereas differentiating cells rapidly lost this capacity. The inability of differentiating cells to form nucleotides from thymidine was not attributed to reduced availability of thymidine due to catabolism but rather was the result of the rapid loss of thymidine kinase activity. As keratinocytes differentiate in suspension culture, they lose 41% of thymidine kinase activity in 8 h and over 90% of activity in 12 h. Our data indicate that loss of capacity to salvage extracellular thymidine for synthesis of nucleotides closely parallels the onset of differentiation in keratinocytes.

Cell Differentiation↗

Antiviral activity of 5-iodo-2'-deoxyuridine and related drugs in human keratinocytes infected in vitro with herpes simplex virus type 1.

5-Iodo-2'-deoxyuridine (IUDR) is a potent topical antiviral agent in experimental animals but is less active in man for treating cutaneous viral infections. We have shown here that IUDR is 5 times less active in human keratinocytes infected in vitro with herpes simplex virus type 1 than in guinea pig embryo cells infected in culture. To account, in part, for this difference in activity of IUDR, we measured the capacity of these different cultures to catabolize and thus inactivate the drug. IUDR is catabolized by thymidine phosphorylase; activity of this enzyme was very high in human keratinocytes in vitro but was very low in guinea pig embryo cells. The antiviral activity of IUDR in human keratinocytes, however, was not increased by inhibiting thymidine phosphorylase; inhibiting thymidine phosphorylase apparently increased the availability of thymidine that would compete with IUDR and, indeed, the activity of IUDR in infected cells was reduced by addition of thymidine to the medium. These data indicate that the catabolism of IUDR and related analogs alters antiviral activity in human keratinocytes.

Animals↗

Local and systemic implications of thymidine catabolism by human keratinocytes.

The human epidermis possesses a very active thymidine phosphorylase with the capacity to catabolize all of the thymidine available to the epidermis from the circulation and from the degradation of DNA in terminally differentiating keratinocytes. This high capacity of keratinocytes to catabolize thymidine could affect local levels of thymidine within the epidermis for DNA synthesis and could contribute to the regulation of the concentration of thymidine in the systemic circulation. Further work is needed to delineate the physiologic role of this keratinocyte enzyme. A practical consequence of the activity of epidermal thymidine phosphorylase is the role it may play in limiting the clinical efficacy of certain thymidine analogs, an important class of antiviral agents.

Cells, Cultured↗

Aplasia cutis congenita in one of monozygotic twins.

Aplasia cutis congenita is an uncommon disorder characterized by a patchy defect of the scalp and other areas of the skin of the newborn. Several familial cases have been reported, including a set of identical twin girls. The disease was unique in our patient, one monozygotic twin.

Diseases in Twins↗

Diethyltoluamide-containing insect repellent: adverse effects in worldwide use.

During the summer of 1978, ten soldiers were seen because of an eruption in the antecubital fossae. All of them had used an insect repellent containing 50% diethyltoluamide a few hours before the eruption had appeared. The symptoms and clinical findings in these cases were those of a burning sensation, erythema, and blisters at the onset, followed in some cases by ulceration and scarring. Precautions in the use of this commonly used repellent should be advised.

Adolescent↗

In vitro analysis of bromine chemical burns with use of full-thickness human skin.

Parameters of bromine injury were studied in vitro with the use of full-thickness human skin (HS) specimens--discards from various surgical procedures. The morphology of in vitro-treated HS resembled that of in vivo-injured skin. The damage was pronounced in the epidermis (destruction of the stratum corneum, and extensive vacuolation of keratinocytes) and the dermis (collagen coagulation), depending on the bromine concentration, exposure time, and application method. A decreased viability of epidermal cells, assayed by dye exclusion, was observed as well. Permeation parameters of bromine via abdominal HS were determined by quantitating bromine concentration in the donor and receiving compartments. The amount of bromine that permeated HS was inversely related to the concentration gradient applied. This in vitro study suggests that prompt treatment and early medical intervention may be required for successful healing of both severe and mild cases of bromine injuries.

Bromine↗

Inappropriateness of cataract extraction: an analysis in two Israeli hospital settings.

OBJECTIVE: To assess and compare the appropriateness of cataract extraction in two Israeli regional hospitals. SETTINGS: Two Israeli hospitals located in different geographic areas. DESIGN: A randomized sample of 150 patients was drawn from a list of all patients who underwent cataract surgery at the two study hospitals during 1995. Detailed extraction of hospital medical records was performed. The appropriateness of cataract surgery was assessed using the Medical Review System, an interactive expert system that assesses the appropriateness of selected medical and surgical procedures. RESULTS: The rates of cataract surgery in the two hospitals were 0.54 and 0.59 operations per 1,000 population, respectively, and the age-adjusted rates per 1,000 population were 5.7 and 6.2, respectively. The percentage of patients with only light perception or hand-motion perception in the operated eye before the operation was 62.2%, with no difference in the two hospitals. There was not a significant difference in the distribution of visual acuity before the operation; however, there was a significant difference in the distribution of visual acuity after the surgery. Rates of inappropriate surgeries in the two hospitals were found to be similar to the inappropriate rate in the United States (1.3%). The preoperative visual acuity of patients undergoing cataract surgery in Israel was inferior to the visual acuity of patients undergoing cataract surgery in the United States. CONCLUSION: To increase quality and cost-effectiveness in the Israeli medical system, future studies of this type are warranted in connection with surgical procedures.

Cataract Extraction↗