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Biomedical subjects

T Kaufman

Publications and source records attributed to T Kaufman.

At least 37 records · Page 2Linked to original sources
PubMed1989

Uterine angiogenic factor induces vascularization of collagen sponges in guinea-pigs.

The need for an adequate blood supply is of prime importance in successful skin grafting and in the take of keratinocyte cultures. Thus, the human uterine angiogenic factor (HUAF) extract, which induces neovascularization of the chorioallantoic membrane (CAM), was employed. The bioassay of HUAF was performed on an in vivo model of subdermally implanted collagen sponges and on sponges implanted into full skin thickness burn wounds in guinea-pigs. The HUAF extract was injected into the sponges every other day for 10 days. Each injection contained 10 micrograms decidual proteins with a total of 50 micrograms/sponge. The animals were sacrificed and the sponge together with the surrounding structures were extirpated, examined macro- and microscopically and by histological techniques. HUAF induced growth of blood vessels from the surrounding vascular bed into the implanted sponges. The angiogenesis was characterized by dense tortuous vessels with centripetal orientation. The control sponges exhibited only sporadic growth of blood vessels. This phenomenon repeated itself in the animals which were inflicted with burn wounds. The present study demonstrates that HUAF extract is also active on the in vivo model of experimental burns and wounds.

Angiogenesis Inducing Agents↗
PubMed1989

Evidence that 1 per cent Meshushit ointment prevents progressive dermal ischaemia of experimental deep partial skin thickness burns: a preliminary, quantitative controlled study.

This study quantitatively assessed the topical effects of Meshushit, a new herbal compound, on the healing process of experimental deep partial skin thickness burns over 27 days. To symmetrical circular burns were inflicted on the back of 15 animals by aluminium templates. The Meshushit and its control vehicle containing 0.1 per cent gentamycin or the control vehicle plus antibiotic alone, were applied topically to randomly selected burns at equal time intervals. Epithelialization and contraction were assessed on postburn days 6, 10, 15, 18, 22 and 27 using a computerized planimeter. The newly formed granulation tissue was assessed histologically on postburn day 27, while the hair follicles were counted in the same sections. Student's t test was used to differentiate the rates of contraction and epithelialization; hair follicle counts and the thickness of the newly formed granulation tissue. None of the animals died during the experiment. The epithelialization and contraction rates did not differ significantly between the test groups. The Meshushit-treated wounds showed a significantly thicker granulation tissue layer as compared to its control (828.72 +/- 46.39 microns vs. 540.78 +/- 37.81 microns, P less than 0.01). The count of hair follicles was significantly higher in the Meshushit-treated burns (23.38 +/- 1.84 vs. 3.76 +/- 0.35, P less than 0.001). It is concluded that the herbal Meshushit ointment enhanced the newly formed granulation tissue and preserved better the hair follicles in the present burn wound model. It is suggested that these findings are due to the preservation of the dermal microcirculation.

Animals↗
PubMed1989

Responses to acute hypoxemia in fetal sheep at 0.6-0.7 gestation.

A majority of previous studies of fetal responses to acute hypoxemia has focused on the response of the sheep fetus greater than 120 days of gestation when many regulatory systems have been established. To assess the response of younger, less well-developed fetuses, we exposed two groups of fetal sheep (I, 84-91 days; II, 97-99 days gestational age) to acute hypoxemia by giving the ewe a gas mixture containing 9% O2 to breathe. We decreased descending aortic PO2 in both groups of fetuses [I, 24 +/- 6 to 14 +/- 3 (SD) Torr; II, 23 +/- 3 to 12 +/- 4 Torr] by a degree similar to that achieved in previous studies of fetuses greater than 120 days of gestation. Mean arterial blood pressure (I, 31 +/- 6; II, 40 +/- 3 Torr) did not change significantly from control values, and heart rate (I, 224 +/- 27; II, 203 +/- 16 beats/min) increased significantly in group II fetuses with hypoxemia. In group I and II fetuses, as in older fetuses, cerebral, myocardial, and adrenal blood flows, measured by the microsphere technique, increased, and pulmonary blood flow decreased. These responses mature early and are likely local vascular responses to decreases in oxygen content. Combined ventricular output and umbilical-placental blood flow decreased significantly in both groups. Unlike the response of the fetus greater than 120 days, acute hypoxemia did not decrease blood flow to the musculoskeletal and cutaneous circulations (group I only), gastrointestinal, or renal circulations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

External longitudinal splitting of the biceps brachii muscle for coverage of repaired brachial vessels: an anatomical study and clinical application.

The external longitudinal splitting of the biceps brachii muscle offers a convenient and safe method for covering exposed vessels in the medial aspect of the arm in cases with loss of soft tissue. This anatomical study reveals rather variable and inconsistent patterns of blood supply to the biceps brachii muscle. The common denominator among the patterns is the fact that the nutrient vessels to the muscle originate in its posterior deep surface and course thereafter in a fan shape upward to the surface of the anterior aspect of the muscle. This microcirculatory pattern permits the external longitudinal splitting of the biceps brachii muscle along the whole anteromedial aspect of the short-headed belly without compromising its blood supply and function. An illustrative case is described.

Adult↗
PubMed1987

Is experimental muscle flap temperature a reliable indicator of its viability?

This study was designed to assess the effects of environmental factors on experimental muscle flap temperature and to critically evaluate temperature as a modality for assessing vascular patency. A brief overview of the physiology of tissue heat transfer is presented. The right vertebral head of the biceps femoris muscle was used in albino New Zealand rabbits for monitoring temperature. Temperature was recorded simultaneously by means of thermocouples placed into the tested muscle, the contralateral control biceps femoris muscle, the ipsilateral control thigh compartment, and rectally (core temperature). The muscle flap temperature was recorded as a function of time during the following flap manipulations: steady state, exposed muscle, muscle elevated and then replaced with pedicles intact, and pedicles ligated. In addition, the effects of environmental manipulations on muscle flap temperature were evaluated. The constant findings demonstrated that the dominant aspects of muscle temperature are the temperature of the surrounding tissue, as well as the prevailing environmental conditions. Vascular occlusion did not alter muscle temperature. In 3 patients who underwent successful free-flap transfer, muscle temperatures were monitored and found to be labile, and altered by environmental manipulations. We concluded that temperature is an unreliable, nonreproducible method of assessing the vascular status of a muscle flap, unless all environmental variables are meticulously monitored and controlled.

Animals↗
PubMed1987

External longitudinal splitting of the tibialis anterior muscle for coverage of compound fractures of the middle third of the tibia.

In this modern era, compound fractures of the middle third of the tibia are relatively common. With the advent of external fixation, these fractures can be more rapidly and effectively dealt with, and attention can be directed to immediate coverage of the exposed bone. External longitudinal splitting of the anterior tibialis muscle offers a convenient and safe method for converting the open fracture to a closed one. The uniqueness of the tibialis anterior muscle is two-fold. It is circumpennate, and it has an internal axial tendon corresponding to almost its total length. Both these features impart to it considerable strength, and the muscle splitting herewith described does not appear to impair its function. Five treated limbs, each with loss of soft tissues overlying compound mid-third tibial fractures, are presented. Rapid healing and virtual absence of bone infection was observed in all cases.

Adult↗
PubMed1986

Early enteral nutrition for mass burn injury: the revised egg-rich diet.

An aggressive enteral nutritional approach has been employed to support our severely burned patients. The diet is based on a daily intake of 5 eggs/10 kg of body weight, incorporated into milkshakes. Twelve patients with severe burns (age, 24 +/- 4 years; burns, 54 +/- 12 per cent of total body surface area (TBSA] were studied. Enteral feeding was initiated on the day of injury and gradually reached the full formula within 3-7 days. Feeding was carried out either orally or through a nasogastric drip or a combination of both, depending on the patient's condition. Each bottle of milkshake contained 2318 kJ, 29 g protein, 51 g carbohydrate and 28.6 g fat in 250 ml. Each millilitre of the diet contained 9.32 kJ. The protein provided 21 per cent of the total calorie intake, while the fat and carbohydrate provided 42 per cent and 37 per cent respectively. The mean daily intake consisted of protein (5 +/- 1.5 g/kg), carbohydrate (8 +/- 0.75 g/kg) and fat (5 +/- 1 g/kg), providing a daily administration of 378-420 kJ/kg. Plasma lipids remained within normal limits during the 40 days of the diet, while serum protein levels rose to normal levels within the first 3 weeks.

Adult↗
PubMed1986

Sodium poisoning: a lethal case of a burned child.

An unusual case of lethal salt poisoning of a burned child is presented. Excessive hypernatraemia and hyperosmolality resulted in an irreversible cascade of events which lead to death despite vigorous attempts to rescue the victim.

Administration, Topical↗
PubMed1986

Studies on the nature of the flap/bed interaction in rodents--Part I: Flap survival under varying conditions.

A flap needs close contact with its bed for optimal flap survival. Using a rat dorsal flap model, flap/bed contact times were varied by use of a sterile polyethylene film. In addition, the flap was modified either by removing the panniculus carnosus or by converting the distal flap into a skin graft. Finally, the effect of using a dressing was assessed. Several observations were made: (1) The initial 6 to 12 hours of a flap's interaction with its bed is critical for optimal survival; (2) fluorescein accurately predicted flap survival upon polyethylene removal; (3) removing the panniculus carnosus increased flap and skin graft survival; (4) dressing allowed flaps and skin grafts to better withstand bed deprivation; and (5) distal flaps and skin grafts under various conditions responded differently to bed deprivation.

Animals↗
PubMed1985

Topical acidification promotes healing of experimental deep partial thickness skin burns: a randomized double-blind preliminary study.

The effects of three buffered solutions with pH values of 3.5, 7.42 and 8.5, respectively, on the healing rate of deep partial skin thickness burns, was followed for 21 days in 16 guinea-pigs. Two symmetrical burns were inflicted on the back of each animal and then each individual wound was dressed with an irrigation disc dressing; solutions were coded (no. 1 to no. 3) and the animals were randomly divided and blindly treated as follows: Group A, solution no. 1 v. solution no. 2 (n = 4); Group B, solution no. 2 v. solution no. 3(n = 4); Group C, solution no. 1 v. solution no. 3(n = 4); Group D, non-irrigated disc dressings (n = 4). The solutions were applied to the surface of the burn wounds at a rate of 0.15 ml/cm2. Dressings were changed every 7 days to assess contraction and epithelialization by a sonic digitizer. On post-burn day 21 the newly formed scar tissue was measured in all wounds. After computation of the healing rate at the end of the study, the data were then related to the coded treating agent. Contraction did not differ in all test groups during the study. Epithelialization was significantly faster in the pH 3.5-treated burns than in the other treated wounds (P less than 0.001). The present study indicates that topical acidification of experimental deep partial skin thickness burns promoted healing. The precise mechanism should be elucidated.

Administration, Topical↗
PubMed1985

Prevention of gastrointestinal bleeding in burns: the effects of cimetidine or antacids combined with early enteral feeding.

The efficacy of prophylactic therapy with cimetidine or antacids combined with early enteral feeding to prevent gastrointestinal bleeding in patients with severe burns was evaluated. Fifty patients with burns exceeding 30 per cent of the total body surface area (TBSA) were divided into two groups, each of them treated by one of these agents in combination with early feeding. Bleeding was not encountered in either group. It is assumed that the combination of either agent with enteral feeding early in the post-burn course equally protected against gastrointestinal bleeding. Because of the ease and lack of side-effects of cimetidine in this series, its use was preferable.

Adult↗
PubMed1985

The salutary effects of the bed on the survival of experimental flaps.

The present study indicates that the distal, random segment of an axial pattern experimental flap can be partially salvaged by employing local pressure, which provides favorable contact with the bed. This portion of the flap could be considered as a composite skin graft. Serial India ink injections demonstrated that its physiological take resembles that of a split-thickness graft, dominantly depending on the blood vessels emerging from its bed, and to a lesser extent on those provided by its proximal segment and adjacent skin edges. Increasing the topical flap humidity hindered, rather than improved, its survival.

Animals↗
PubMed1985

The microcirculatory pattern of the transverse-abdominal flap: a cross-sectional xerographic and CAT scanning study.

Following unilateral iliac artery injection of radiopaque Microfil in cadavers, coronal sections of the anterior abdominal wall at 1-cm intervals were obtained employing computerized axial tomography of the intact specimen as well as xerography of frozen slices. Because they avoid the distortion and disruption of the vasculature induced by anatomical dissection, these studies clearly indicate that the arterial supply to zones 3 and 4 of the transverse rectus abdominis musculocutaneous flap is derived through the following systems: the subdermal plexus, and the superficial subcutaneous tissue crossover system. This study substantiates previous anatomical assumptions.

Abdominal Muscles↗
PubMed1985

Drug-loaded synthetic dressings: effect on contraction, epithelialization, and collagen synthesis of deep second-degree experimental burns.

The effect of drug-loaded synthetic dressings on the contraction, epithelialization, and collagen synthesis of deep second-degree burns was followed for 21 days in 44 guinea pigs. Two symmetrical burns were inflicted on the back of each animal; the animals were then divided at random into the following test groups: Group 1 (n = 10), a prefabricated, precut, pliable, and noncracking dressing designated as Dimac (DM), versus Dimac plus 2% silver sulfadiazine (DM+); Group 2 (n = 10), Hydron loaded with 2% silver sulfadiazine (HAgS) one versus fine mesh gauze and 1% silver-sulfadiazine cream (GAgS); Group 3 (n = 12), Hydron (Hyd) versus fine mesh gauze (G); Group 4 (n = 4), fine mesh gauze versus Telfa (Tel); Group 5 (n = 6), Telfa versus Telfa; Group 6 (n = 2), gauze versus gauze. Epithelialization and contraction rates were measured at dressing changes on postburn days 6, 12, 18, and 21, with a computerized sonic digitizer. Collagen biosynthesis was measured from the wound scar on PBD 21 and expressed as relative collagen biosynthesis. Contraction on PBDs 18 to 21 was significantly lower (p less than 0.05) in the DM and DM+ treated burns. Epithelialization of the DM and DM+ treated groups on PBD 21 was significantly (p less than 0.05) higher than in the Hyd, HAgS, GAgS, and Tel treated burns, and did not differ from the G treated wounds. The relative collagen biosynthesis method was inapplicable to this burn wound model.

Animals↗