PubMed Health⌕ Search

Biomedical subjects

G Mark

Publications and source records attributed to G Mark.

At least 37 records · Page 2Linked to original sources

[Temporary balloon catheter occlusion for control of bleeding of a blunt injury of the proximal axillary artery. Case report and review of the literature].

We describe the successful placement of an intra-arterial balloon catheter by a femoral approach in order to occlude the proximal arterial end and to control massive bleeding in a patient with rupture of the left axillary artery after blunt scapulo-thoracic dissociation. To our knowledge this technique has so far not been reported in Europe. It allows rapid control of bleeding, minimizes blood loss and markedly facilitates pre- and perioperative management in selected cases. The authors review the relevant literature dealing with this topic.

Adult↗

[Ambulatory hand surgery].

The majority of surgical interventions about the hand can be done on an outpatient basis and in private practice; however, the surgeon must be well-trained in hand surgery and should master all forms of local and regional anesthesia, permitting an atraumatic technique. In addition, he must be prepared to handle any peri- and intraoperative complication and should be able to refer the patient to a close-by hospital in case of need. Since the aftercare appears to be of paramount importance for a successful outcome, the postoperative rehabilitation must be guaranteed as well. As all these conditions require qualified manpower and a good infrastructure, hand surgery is probably best performed within a small group of practising surgeons.

Ambulatory Surgical Procedures↗

[Vascular injuries--management in a non-university central hospital].

In a retrospective study the surgically treated vascular injuries (n = 35) of the last 10 years were evaluated. One third of the patients had multiple trauma and in 57% of the cases vascular injury was accompanied by a fracture. All patients (n = 28) except those who underwent delayed amputation (amputation rate 14%) have been followed personally for an average of 5.1 years. 90% of these patients showed an excellent or acceptable longtime result in regard to vascularity, nobody complained of claudication. Diagnosis of a vascular injury was mostly confirmed by direct surgical exploration, only one third of the lesions were diagnosed by arteriogram. A positive signal in Doppler examination does not exclude vascular injury and therefore cannot replace arteriography or exact clinical evaluation.

Adult↗

Management of displaced supracondylar fractures of the humerus in children.

A series of 33 children with displaced supracondylar fractures of the humerus (SFH) were all treated operatively by open reduction and internal fixation or by closed reduction and percutaneous pinning. A follow-up study was performed on average 29 months (range 3-63 months) after the injury. In 18 per cent of cases primary neurovascular injury was observed and confirmed at operation. Of these patients 32 had open reduction and internal fixation by K-wires; in only one case was closed reduction and percutaneous pinning attempted. If there was preoperative neurological deficit, the nerves were visualized; however nerve suture was not required in our series. In one case we had to reconstruct both the brachial and radial arteries because of intimal lesions totally occluding the vessels. The average hospital stay was 9 days, including pin removal, which was usually performed about 4-5 weeks later, at the time of plaster removal. By Innocenti's criteria, 27 of 30 patients reviewed had an excellent result; three had a good result and three patients were lost to follow-up. There were no complications due to the operation, such as wound healing problems, infections or nerve lesions. In the light of our experience and of the good results, we recommend that displaced SFH be managed by open reduction and internal K-wire fixation. Percutaneous pinning is a good alternative method when closed reduction is successful at the first attempt.

Bone Nails↗

[Infection of the hand: a specific disease picture].

Certain anatomical and physiological features are responsible for the specific clinical presentations of hand infections: The dorsum of the hand possesses a loose mobile areolar layer, whereas the gripping function of the palm has determined the development of a dense, firmly anchored sheet layer of connective tissue. It follows that infections of the dorsum of the hand can spread easily and give rise to extensive cellulitis. This cannot occur on the palmar aspect, where infection always tracks along the path of least resistance into the deep tissues, rapidly reaching the functionally important structures of the flexor compartments, including the subfascial compartments of the deep palmar space and the space of Parona in the forearm. A similar chain of events characterizes infections of the thenar and hypothenar eminences. Distal finger infections around the nail are a separate clinical entity with a considerable risk of running a chronic course and involving bone or the distal interphalangeal joint. In this case the sequence leads form subcutaneous infection or paronychia via bone infection to joint sepsis. There is considerable scope for misdiagnosis of hand infections, and inappropriate conclusions may lead to serious consequences for future function of the hand. The treatment of hand infections is demanding, time-consuming and not infrequently requires the infrastructure of a hospital clinic; therefore, in cases of doubt, early referral is always advisable.

Bacterial Infections↗

[Abdominal tuberculosis and open lung tuberculosis caused by mycobacterium bovis].

Abdominal tuberculosis is a rare disease in Western countries and remains difficult to diagnose. The most frequent symptoms are abdominal pain, weight loss, fever, vomiting, constipation and/or diarrhea. Clinical findings include abdominal tenderness, a palpable mass (often in the right fossa due to ileocecal infection), paleness, cachexia and ascites. Suggested radiological investigations include plain abdominal film, upper GI-series and barium enema. Chest X-rays often show signs of either active or inactive tuberculosis. Sputum and gastric juice should be cultured. Coloscopy serves to sample specimens for histology and bacteriology and may help to confirm the diagnosis, which is, however, not ruled out by negative findings. The same holds good for peritoneal biopsy and laparoscopy. Bowel perforation and ileus are frequent complications and always require surgery, whereas uncomplicated cases can be treated by drugs only.

Adolescent↗

Malignant transformation of human bladder epithelial cells by DNA transfection with the v-raf oncogene.

Transfection of the v-raf oncogene into immortalized, nontumorigenic human bladder epithelial cells resulted in the isolation of two tumorigenic transformants. Both were identified as human and of the same origin as the parent cell line by human leukocyte antigen typing and Southern blot analysis. Both the primary tumorigenic transfectants and the cell lines established from the induced tumors expressed v-raf mRNA and v-raf protein. In both tumorigenic transformants the level of c-myc mRNA was enhanced compared with that of the parent cell line.

Animals↗

[Intra-articular fracture of the distal radius: results following osteosynthesis with a support plate].

The treatment of comminuted intra-articular fractures of the distal radius often requires an operative fixation. Beside the recently recommended external fixator, the support plate fixation offers a helpful alternative to treatment. Between 1980 and 1986, 30 wrists in 29 patients with intra-articular fractures of the distal radius were stabilized with a buttress plate an the Kantonsspital Chur, Switzerland. The mean follow-up-time was 15 months. These follow-ups showed that the buttress plate in treatment of complicated intra-articular fractures allows a satisfactory reduction and stabilization with restoration of the articular congruity and the possibility for early active assisted motion. Buttress plate fixation still remains a demanding technique, which in complicated cases, should be reserved for the experienced surgeon.

Adult↗

[Special utilization potentials of the external fixator in severe complex hand injuries].

Complex injuries to the hand may cause considerable problems in the aftertreatment. Two possibilities are described, which may facilitate and optimize the postoperative care of the severely injured hand: 1. In case of an inguinal pedicle flap, the temporary stabilization of the hand against the pelvis by means of external fixation is advocated. 2. After multiple extensor tendon repair, the temporary immobilization of the wrist, leaving the fingers free to move, by means of a small fixateur externe is suggested.

Adolescent↗

[The treatment of dislocated supracondylar humerus fractures in childhood].

33 children with displaced SFH were all treated operatively by open reduction and internal fixation or closed reduction and percutaneous pinning. A follow-up study was performed on average 29 (range 3-63) months after the injury. In 18% of the cases an initial injury of the neurovascular structures was observed and documented during the operation. 32 times open reduction and internal fixation by K-wires was performed, only once, closed reduction and percutaneous pinning was attempted. In the presence of a preoperative neurologic deficit, the nerves were always visualised, never, however, a nerve suture was necessary. In one case we had to reconstruct both the arteria brachialis and radialis because of intima lesions with total obstruction of the vessels. The average time of hospitalization was 9 days, which includes the time for removal of the pins, which was usually performed about 4,5 weeks later simultaneously with the removal of plaster. Using Innocenti's criteria, 27 of 30 reviewed patients had an excellent result, 3 had a good result. Early complications due to the operation such as wound healing problems, infection or nerve lesions did not occur. 3 patients could not be reached any more. We recommend for the management of the displaced SFH open reduction and internal fixation by K-wires as the method of choice. Percutaneous pinning is a valid alternative when closed reduction succeeds easily at the first attempt.

Child↗

[After-care following hand surgery].

In hand surgery the after-care constitutes a most important part of the treatment, if full reconstitution of function is to be achieved. We distinguish mainly three periods which may vary in duration: the immediate postoperative period, the period of mobilisation and the specific rehabilitation with ergotherapy. In the early postoperative period, the main concern goes to the wound care, prophylaxis and treatment of pain and swelling by careful and adequate immobilisation and positioning of the hand on one side and mobilisation of elbow and shoulder on the other. The second period of mobilisation of the hand starts once the wounds are healed and the swelling has subsided. The patient is instructed in actively mobilising his injured hand and fingers with the support of resting and dynamic splints. Finally the actual rehabilitation programme is started with application of increasing load and strength as well as building up of the fine sensory and motor function of the fingers.

Bandages↗

Expression of recombinant platelet-derived growth factor A- and B-chain homodimers in rat-1 cells and human fibroblasts reveals differences in protein processing and autocrine effects.

The autocrine effects of platelet-derived growth factor (PDGF) A- and B-chain homodimers (PDGF-AA and PDGF-BB) on rat-1 cells and human fibroblasts have been investigated by using human PDGF A- and B-chain cDNA clones expressed in a retroviral vector. Infection with replication-defective virus carrying the B-chain cDNA resulted in a phenotypical transformation resembling that induced by simian sarcoma virus. The resulting cells were focus forming in monolayer cultures, grew to high saturation densities, and formed large colonies in soft agar. The PDGF A-chain transfectants showed no transformed morphology and lacked focus-forming activity but grew to high saturation density in monolayer culture and formed small colonies in soft agar. A similar but weaker effect was obtained with an A-chain cDNA variant containing a 69-base-pair insertion in the 3' end of the protein-coding domain. A- and B-chain transfectants released PDGF receptor-competing activity into the medium, but only the medium conditioned by the B-chain transfectants possessed potent mitogenic activity on human fibroblasts. Both types of transfectants had downregulated levels of PDGF receptors; however, the B-chain transfectants were downregulated to significantly lower levels. Metabolic labeling and immunoprecipitations with PDGF antiserum showed that the PDGF B-chain protein was processed to a 24-kilodalton cell-associated and a 30-kilodalton secreted dimeric protein. The A-chain protein was rapidly secreted as a 31-kilodalton dimeric protein. The present study shows a marked difference in the autocrine effects of PDGF-AA and -BB expressed under the control of a retroviral promoter and suggests that different biological properties may be assigned to these two PDGF isoforms.

Animals↗

HTLV-I--associated B-cell CLL: indirect role for retrovirus in leukemogenesis.

Serum containing antibodies to the human T-lymphotropic virus type I (HTLV-I) has been observed at a higher than expected frequency in patients with B-cell chronic lymphocytic leukemia (CLL) in an area endemic for HTLV-I. An attempt was made to determine whether the cells from patients with this leukemia were HTLV-I antigen-committed B cells that had undergone malignant transformation. Cells from two HTLV-I seropositive Jamaican patients with CLL were fused with a human B-lymphoblastoid cell line. The hybridoma cells that resulted from the fusion of CLL cells from patient I.C. produced an immunoglobulin (IgM) that reacted with the p24 gag protein from HTLV-I, HTLV-II, and HTLV-III (now referred to as HIV), but showed preferential reactivity with HTLV-I. The specific immunoglobulin gene rearrangement (IgM, kappa) in the CLL cell was demonstrated in the hybridoma cell line, indicating that the captured immunoglobulin was from the CLL cells. The IgM secreted by the fusion of CLL cells from patient L.L. reacted only with HTLV-I-infected cells and with the HTLV-I large envelope protein (gp61) on Western blots. The CLL cells from these patients appear to be a malignant transformation of an antigen-committed B cell responding to HTLV-I infection, suggesting an indirect role for this retrovirus in leukemogenesis.

Antibodies, Viral↗

Structure and biological activity of human homologs of the raf/mil oncogene.

Two human genes homologous to the raf/mil oncogene have been cloned and sequenced. One, c-raf-2, is a processed pseudogene; the other, c-raf-1, contains nine exons homologous to both raf and mil and two additional exons homologous to mil. A 3' portion of c-raf-1 containing six of the seven amino acid differences relative to murine v-raf can substitute for the 3' portion of v-raf in a transformation assay. Sequence homologies between c-raf-1 and Moloney leukemia virus at both ends of v-raf indicate that the viral gene was acquired by homologous recombination. Although the data are consistent with the traditional model of retroviral transduction, they also raise the possibility that the transduction occurred in a double crossover event between proviral DNA and the murine gene.

Amino Acid Sequence↗