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J Hoch

Publications and source records attributed to J Hoch.

At least 73 records · Page 4Linked to original sources
PubMed1996

[Fetal weight-adjusted intrauterine IgG therapy in neonatal alloimmune thrombocytopenia].

Fetal alloimmune thrombocytopenia is caused by materno-fetal transfer of platelet antibodies. Since the thrombocytopenic fetus is threatened by intracranial hemorrhage, prenatal observation and, if necessary, treatment is required. However, the benefit of therapeutic options, including intravenous IgG (ivIgG), platelet transfusions or fetal IgG transfusions is still controversial. In this study we have evaluated the effect of intrauterine IgG and intraumbilical platelet transfusions on fetal platelet counts. All patients were multiparous women who were immunized against the Zwa antigen during previous pregnancies and had given birth to at least one severely thrombocytopenic infant. First umbilical blood was sampled at the 20th week of gestation. Fetal treatment of IgG was given, on av erage, over 9 weeks. In all cases, fetal IgG levels rose significantly whereas platelet counts did not increase following fetal IgG treatment. We conclude that fetal IgG infusions have no detectable effect on fetal allo-immune thrombocytopenia. Since platelet counts can be very low as early as 20 weeks of gestation, careful fetal monitoring by umbilical blood sampling is essential. Platelet transfusions in short intervals appear to be the only effective regimen to increase platelet counts in thrombocytopenic fetuses at risk.

Adult↗
PubMed1995

Ultrastructural and biochemical modifications of collagen from tissue of Morbus Dupuytren patients.

Small angle X-ray diffraction and biochemical analyses were carried out on normal palmar aponeurosis and on tissue from patients suffering from Dupuytren contractures (MD). Pathological tissue exhibits a higher overall content of collagen III. Type I collagen extracted from pathological tissue has a melting point of 0.8 degrees C higher than that of normal collagen. The only chemical differences compared to normal collagen I are 50% overhydroxylation of lysyl residues and a reduced amount of diglycosylated hydroxylysine residues. Analysis of the electron density distribution inside the collagen repeating period of MD-samples reveals disordered molecular packing in MD samples compared to in normal collagen. The disorder, which is higher in the gap region, is considerably reduced upon stretching.

Carbohydrate Sequence↗
PubMed1995

vpr deletion mutant of simian immunodeficiency virus induces AIDS in rhesus monkeys.

In previous experiments, animals infected with SIVmac239 containing a point mutation in the vpr and nef genes developed AIDS-like symptoms after early reversion of the vpr and nef genes. Here we show that two animals in which the nef gene but not the vpr gene had reverted in the first few months did not develop disease during a 3-year observation period even after reversion to a functional vpr gene 70 weeks postinfection. To study the influence of a stable vpr mutation on virus load and pathogenesis, a 43-bp deletion was introduced into the vpr gene of SIVmac239on, a nef-open mutant of SIVmac239. Four rhesus monkeys were inoculated with the vpr deletion mutant (SIV delta vpr), and two control animals were infected with SIVmac239on. Both control animals had persistent antigenemia, high cell-associated virus loads, and elevated neopterin levels. They had to be euthanized 20 and 30 weeks postinfection because of AIDS-related symptoms. However, all four rhesus monkeys inoculated with SIV delta vpr showed only transiently detectable antigenemia. The cell-associated virus loads were high in three of the four animals. Two animals with AIDS-like symptoms had to be euthanized 71 and 73 weeks postinfection. The two remaining monkeys infected with SIV delta vpr were still alive 105 weeks postinfection. In contrast to the SIVmac239on-infected animals, SIV delta vpr-infected animals had strong humoral immune responses and intermittent cellular immune responses to SIV antigens. Our data show that a functional vpr gene is not necessary for pathogenesis. However, vpr-deficient SIVmac239 variants might be slightly attenuated, allowing some animals to resist progression to disease for an extended period of time.

Animals↗
PubMed1995

[Laparotomy closure with continuous polydioxanone sutures].

The authors describe the method of closure of laparotomic wounds by means of an atraumatic continuous PDS loop suture. Based on evaluation of a group of 166 patients they appreciate the positive aspects of the technique of this suture, in particular the speed, easy implementation and safe closure of laparotomy. As regard the sewing material, they value highly the quality of atraumatic fibres which are firm and do not irritate the tissues.

Dioxanes↗
PubMed1995

[Augmentin and Tiberal in elective colorectal surgery (comparison of serum and tissue levels and clinical results].

In a group of 340 patients subjected to colorectal surgery for antimicrobial prophylaxis amoxicillin clavulanate (Augmentin) or ornidazole (Tiberal) was used, in both instances as short-term monoprophylaxis. To test the effectiveness of prophylaxis, the clinical results were evaluated, expressed by the number of infectious complications, as well as serum and tissue levels of the two preparations used for prophylaxis. In serum and tissue they reached the MIC level of the tested microbial spectrum; an inadequate level was found in all probands in subcutaneous adipose tissue. The clinical result of 4.8% infectious complications when using ornidazole and 3.2% when using amoxicillin clavulante resp. is considered as evidence of the effectiveness and correct selection of preparations and also of sufficient short-term prophylaxis.

Aged↗
PubMed1994

[Transfusion associated acute pulmonary insufficiency. Diagnostic confirmation by the demonstration of granulocytic antibodies].

In two patients, a 50-year-old woman (case 1) and a 2-year-old girl (case 2) acute shortness of breath requiring artificial ventilation developed 3-5 hours after infusion of two erythrocyte concentrates in case 1 and unfiltered platelet-enriched plasma (20 ml/kg) in case 2. The chest radiograph showed diffuse infiltrations in the lungs of both patients. After administration of catecholamines and respirator therapy, extubation was possible in the first patient after two days, in the second after five days. In neither case had there been any evidence of hypervolaemia, heart failure or infection to explain the lung findings. However, the serum of case 1 and the serum of the platelet donor had antibodies against granulocytes. The granulocyte-compatibility test (between patient serum and donor granulocytes) was positive. This confirmed the clinical suspicion of transfusion-related acute lung injury (TRALI). However, demonstration of antibodies was not only important for the diagnosis, but made it possible to recognize a blood donor whose serum contained antibodies against granulocytes which can provoke TRALI.

Catecholamines↗
PubMed1994

Maternal intravenous immunoglobulin treatment does not prevent intracranial haemorrhage in fetal alloimmune thrombocytopenia.

In fetal alloimmune thrombocytopenia (FAIT) the fetus is threatened by intracranial haemorrhage (ICH); therefore early diagnostic and therapeutic intervention is required. We followed the clinical course of a 30-year-old woman during her fifth pregnancy after she had given birth to a child with alloimmune thrombocytopenia due to anti-Zwa. The fetus was monitored by 13 fetal blood samplings (FBS) always followed by transfusion of either maternal or compatible donor platelets. Intravenous immunoglobulin (ivIg) treatment of the mother was begun at 20 weeks of gestation when the fetal platelet count was 36 x 10(9)/l. The fetal platelets were typed Zwa positive by DNA analysis. Despite 11 weeks of maternal ivIg treatment fetal platelet counts progressively declined to 6 x 10(9)/l and ICH occurred. Subsequently, the fetus was successfully managed by intrauterine platelet transfusions at shorter intervals (3-5 days) and elective Cesarean section was carried out at 35 weeks of gestation. We conclude that maternal ivIg treatment does not prevent ICH in FAIT. The treatment of choice for severely affected cases is serial FBS combined with transfusion of compatible platelets.

Antigens, Human Platelet↗
PubMed1994

[Are "Busch fracture", "avulsion fracture of the extensor tendon" or "fracture of the dorsal terminal finger joint" synonyms? Anatomic studies of the insertion of the extensor aponeurosis and significance in hand surgery].

With the help of thick transparent cross-sections of fingers, it has been shown that fibers of the extensor aponeurosis insert distal to the avulsed fragment of the distal phalanx. The consequence for hand surgery is not to expose the fragment through a dorsal incision but through a mid-lateral one. In this way, the distant parts of the aponeurosis distal to the fracture remain intact and there is no break in the continuation of the dorsal extensior plate.

Adult↗
PubMed1994

[Prenatal substitution therapy in fetal alloimmune thrombocytopenia].

Fetal alloimmune thrombocytopenia is caused by maternofetal transfer of platelet antibodies. Since the thrombocytopenic fetus is threatened by intracranial hemorrhage, prenatal observation and, if necessary, treatment is required. However, the benefit of therapeutic options, including intravenous IgG (ivIgG) or platelet transfusions, is still controversial. In this study we have evaluated the effect of maternal ivIgG and intraumbilical platelet transfusions on fetal platelet counts in 7 cases. All patients were multiparous women who were immunized against the Zwa antigen during previous pregnancies and had given birth to at least one severely thrombocytopenic infant. First umbilical blood was sampled at the 26th week of gestation. Maternal treatment of ivIgG was given over 7 weeks, the mean number of intrauterine platelet transfusions was 5.9. In 6 of 7 cases the basal platelet count before transfusion did not rise or even further decreased during maternal ivIgG treatment. In one case the baseline platelet count increased from 18,000/microliter to 60,000/microliter during ivIgG. We conclude that, in general, ivIgG alone has no detectable effect on fetal alloimmune thrombocytopenia. Since platelet counts can be very low as early as 20 weeks of gestation, careful fetal monitoring by umbilical blood sampling is required. Platelet transfusions in short intervals appear to be the only effective regimen to increase platelet counts in extremely thrombocytopenic fetuses.

Antigens, Human Platelet↗
PubMed1994

[Transfusion-associated acute pulmonary insufficiency: a rare, but life-threatening transfusion reaction].

Two patients developed within several hours after blood transfusion severe shortness of breath which required temporary artificial ventilation. X-ray pictures of the chest showed pulmonary edema in both patients. No cardiac causes for edema were found. Detection of granulocyte antibodies in the sera of one patient and one blood donor confirmed the suspected diagnosis of transfusion-related acute lung injury.

Acute Disease↗
PubMed1993

[Can the system for ordering blood for elective surgery be improved?].

The authors investigated the effectiveness of ordering of blood for elective surgery. Analysis of a group of 333 operated patients revealed that blood was administered only in 9% of the operations, i.e when compared with the number ordered the ratio ordered: issued was 13:1. Based on their own experience the authors present the possibility how to improve the blood ordering system from the surgical as well as blood bank activity aspect.

Blood Banks↗
PubMed1993

[Arterial embolization in the care of massive hemorrhage from the rectum].

Haemorrhage from distal parts of the GIT is as a rule associated with diagnostic and therapeutic difficulties, in particular when massive haemorrhage is involved. The authors describe a group of three patients where the source of haemorrhage was an inoperable rectal tumour. This problematic condition was successfully treated by embolization of the upper rectal artery.

Aged↗
PubMed1993

[Antibody induction after intrauterine interventions].

Immunohematologic and clinical data, i.e., antibody profile, location of the placenta, mode of cordocentesis, obtained from 48 pregnant patients with irregular erythrocyte antibodies during the last 2 years have been retrospectively evaluated. All fetuses of the patients received intrauterine transfusions for the treatment of fetal erythroblastosis. In 16 (33%) patients (group I) a secondarily induced antibody was detected after the onset of intrauterine transfusion therapy. 32 (67%) patients (group II) did not further develop new antibody specificities. Group I exhibited a significantly different distribution in the location of the placenta (p < 0.05; chi 2 test) as compared with a nonselected control group of pregnant women. In group I a 5-fold higher rate of anterior than posterior placenta location was found. The mode of cordocentesis differed significantly (p < 0.01; chi 2 test) between group I and group II patients. In group I a significantly higher rate of transplacental punctures than in group II had been performed. This has to be considered to be causative for the secondary sensitization. Therefore, the secondary induction of antibodies by invasive intrauterine interventions in our patients depended indirectly on the location of the placenta and directly on the mode of the puncture (trans- vs. paraplacental access).

Adult↗
PubMed1992

Characterization and nucleotide binding properties of a mutant dihydropteridine reductase containing an aspartate 37-isoleucine replacement.

Kinetic constants for the interaction of NADH and NADPH with native rat dihydropteridine reductase (DHPR) and an Escherichia coli expressed mutant (D-37-I) have been determined. Comparison of kcat and Km values measured employing quinonoid 6,7-dimethyldihydropteridine (q-PtH2) as substrate indicate that the native enzyme has a considerable preference for NADH with an optimum kcat/Km of 12 microM-1 s-1 compared with a figure of 0.25 microM-1 s-1 for NADPH. Although the mutant enzyme still displays an apparent preference for NADH (kcat/Km = 1.2 microM-1 s-1) compared with NADPH (kcat/Km = 0.6 microM-1 s-1), kinetic analysis indicates that NADH and NADPH have comparable stickiness in the D-37-I mutant. The dihydropteridine site is less affected, since the Km for q-PtH2 and K(is) for aminopterin are unchanged and the 14-26-fold synergy seen for aminopterin binding to E.NAD(P)H versus free E is decreased by less than 2-fold in the D-37-I mutant. No significant changes in log kcat and log kcat/Km versus pH profiles for NADH and NADPH were seen for the D-37-I mutant enzyme. However, the mutant enzyme is less stable to proteolytic degradation, to elevated temperature, and to increasing concentrations of urea and salt than the wild type. NADPH provides maximal protection against inactivation in all cases for both the native and D-37-I mutant enzymes. Examination of the rat DHPR sequence shows a typical dinucleotide binding fold with Asp-37 located precisely in the position predicted for the acidic residue that participates in hydrogen bond formation with the 2'-hydroxyl moiety of all known NAD-dependent dehydrogenases. This assignment is consistent with x-ray crystallographic results that localize the aspartate 37 carboxyl within ideal hydrogen bonding distance of the 2'- and 3'-hydroxyl moieties of adenosine ribose in the binary E.NADH complex.

Amino Acid Sequence↗
PubMed1992

Heparin-induced thrombocytopenia in the newborn.

This pilot study was initiated to determine whether heparin-induced thrombocytopenia occurs in the newborn and whether thromboembolic complications in the newborn could be related to heparin-induced thrombocytopenia. Thirty-four infants in whom thrombocytopenia (less than 70,000/mm3) (n = 23), precipitous (30% to 50%) fall in platelet count (n = 5), or thromboses (n = 6) developed while they were receiving heparin were studied. Heparin-associated antiplatelet antibodies were demonstrated in 14 infants by platelet aggregation testing. The average gestational age (29 +/- 6 weeks); birth weight (1300 +/- 945 gm); and platelet count at birth (234,000/mm3 +/- 111,000/mm3) of these 14 infants did not differ statistically from the 20 infants without heparin-associated antiplatelet antibodies. An umbilical artery catheter was inserted in all infants except a single patient from each group. Aortic thrombosis was documented by abdominal ultrasonography in 11 of 13 (85%) infants with heparin-associated antiplatelet antibodies. One patient died with a midgut volvulus before the aorta could be examined. Five aortic thromboses were detected in the 20 infants without heparin-associated antiplatelet antibodies. Bleeding was not associated with the heparin-induced thrombocytopenia. One patient with previously demonstrated thrombocytopenia and heparin-associated antiplatelet antibodies had recurrent thrombocytopenia when reexposed to heparin; her platelet count recovered after heparin withdrawal. Thus heparin-induced thrombocytopenia does occur in preterm and term infants receiving heparin and is associated with arterial thromboses. Therefore infants receiving any form or amount of heparin must be carefully monitored for heparin-induced thrombocytopenia.1+

Autoantibodies↗
PubMed1992

The fatty acid synthase (FAS) gene and its promoter in Rattus norvegicus.

Screening of rat liver genomic libraries yielded 5 overlapping clones for rat fatty acid synthase (FAS). From these clones we determined the 18,170 bp sequence of the rat FAS together with 5,028 bp of the 5'-flanking region and 515 bp of the 3'-adjacent genomic sequence. The two FAS transcripts which differ only in the positions of their polyadenylation/termination sites consist of one untranslated and 42 translated exons. Surprisingly, the substrate binding site for enoyl reductase, one of the FAS component functions, is interrupted by an intron. The sizes and the boundaries of the individual domains could be mapped in relation to the exon/intron structure of the gene. These eight partial functions coincide with discrete units of exons. The acyl carrier protein with its prosthetic 4'-phosphopantetheine group is located within a single exon supporting the idea that rat FAS has evolved by gene fusion. Using primer extension the main transcription start site of the FAS mRNA in both hepatic and mammary gland tissues was located at 5,028 bp in the sequence determined. As expected of a gene which is pretranslationally regulated the 5'-flanking region contains, in addition to TATA and CAAT boxes, consensus sequences for several DNA binding proteins.

Amino Acid Sequence↗
PubMed1992

[Primary resection of the large intestine].

The authors evaluate their own group of 49 patients subjected in 1982-1990 to primary resection of the large intestine with an immediately established anastomosis. 32 patients (65.31) recovered per primam and were discharged on average after 14.9 days. A disorder of the anastomosis was recorded in 5 patients, i.e. on 10.2%. In the conclusion the authors express conditions essential for the safety of these operations.

Anastomosis, Surgical↗