Kinetics of protein tyrosine phosphorylation in sperm selected by binding to homologous and heterologous oviductal explants: how specific is the regulation by the oviduct?

Essential steps of the capacitation process take place in the oviductal isthmus. A crucial step in the process of capacitation is the phosphorylation of membrane proteins. The aims of this work were (1) to study the effect of dog sperm binding to oviductal epithelium on tyrosine phosphorylation and (2) to investigate the specificity of regulation of molecular changes by the oviduct of different species by comparing the numbers of canine sperm bound to heterologous (porcine) and homologous epithelium, and the kinetics of tyrosine phosphorylation. Semen was collected from four healthy dogs and washed through a Percoll gradient. Explants, small pieces of epithelium, were cut from porcine and estrous bitch oviducts. During 6 h of coincubation in Tyrode medium, the numbers of bound sperm were counted by microvideographic observation, and the state of tyrosine phosphorylation was determined immunocytochemically after 3, 30, 90, 180 and 360 min. Canine sperm bound in similar numbers to homologous and heterologous explants. Increasing tyrosine phosphorylation of tail proteins and subsequent phosphorylation of sperm head proteins were observed. Binding occurred mainly in sperm with non-phosphorylated heads (approximately 2% phosphorylated), while higher proportions of head-phosphorylated cells were found in unbound populations (approximately 40-60%;P<0.05). The head phosphorylation progressed significantly during incubation in unbound spermatozoa (P<0.05), while it was suppressed in bound suspensions. The rate of tyrosine phosphorylation of sperm tail proteins was higher in cells bound to explants than in unbound cells or in those incubated in control medium. There were no significant differences with respect to the kinetics of tyrosine phosphorylation between the two coincubation systems. These observations support the hypothesis that spermatozoa with non-phosphorylated heads preferentially attach to epithelial cells. Tyrosine phosphorylation of sperm head proteins and capacitation are delayed in spermatozoa in close contact with oviductal epithelium. This mechanism appears to be species-independent, as sperm bound similarly to pig and dog oviduct explants, and similar phosphorylation kinetics were observed in both types of tissue.

Regulation of capacitation of canine spermatozoa during co-culture with heterologous oviductal epithelial cells

Progress of essential steps of the capacitation is coordinated in the oviductal isthmus, where sperm are stored in close contact with the epithelium. A crucial capacitational event is the phosphorylation of sperm membrane proteins. Regulation of the tyrosine phosphorylation by the oviduct has not been examined in dog sperm yet. The aim of this work was to study the effect of dog sperm binding to porcine oviductal epithelium on capacitation-induced cellular and molecular changes. Epithelial cells were stripped from the oviducts of post-puberal sows and cultured for 5-7 days at 39 degrees C and 5% CO2 on Biomatrix-covered Chamber slides. Sperm washed through Percoll was co-incubated with the oviductal epithelium cell cultures in a bicarbonate Tyrode's medium. During co-incubation, sperm membrane changes, the state of tyrosine phosphorylation and motility were determined after 3, 30, 90, 180, 240 and 360 min. Significant increases in the percentage of capacitated and dead cells were observed in unbound sperm, while bound sperm remained uncapacitated, live and motile. An increasing tyrosine phosphorylation of tail proteins in bound, unbound and control sperm suspensions and a subsequent phosphorylation of head proteins in unbound and control sperm suspensions were observed. A significant difference regarding head phosphorylation (p < 0.05) was found between sperm bound to oviductal epithelium and unbound sperm. Binding occurred mainly in sperm with non- phosphorylated heads, while higher proportions of phosphorylated cells were found in unbound populations. The head phosphorylation progressed significantly during incubation in unbound spermatozoa (p < 0.05); however, it was suppressed in population of sperm attached to oviductal epithelium. Significant correlations between motility parameters related to hyperactivation and tail phosphorylation were found in unbound sperm. These observations support the hypothesis that spermatozoa with non-phosphorylated heads preferentially attach to epithelial cells. It can be concluded that tyrosine phosphorylation of head membrane proteins and capacitation are delayed in canine spermatozoa being in closed contact with oviductal epithelium.

[Sepsis--continual pathogenetic, diagnostic and therapeutic problem]

Sepsis is defined as systemic inflammatory response syndrome (SIRS) caused by infection. Massive activation of humoral and cellular mechanisms of host defense is present and can lead to a multiple organ dysfunction syndrome. Sepsis is good example, that inflammation binds with considerable energetic and metabolic effort of organism i.e. demand for oxygen, protein and microelements. The effort during SIRS exceeds compensatory abilities of organism, cause shock and death. The high mortality (40-70% in the case of septic shock) is a good illustration of the therapeutic problem. In the paper pathogenesis, diagnosis and therapy of sepsis was described. Pathogenetic importance of intoxication was explained--massive intoxication (for example by Staphylococcal enterotoxin) without infection cans lead to SIRS too. Precious advice in selection of antibiotic were given. Advantage penicillins and karbapenems over cephalosporins result from binding to PBP 2 or 1, considerably smaller release of free endotoxin and smaller induction Jarish-Heixhaimer's reaction. The side effect stimulates inflammation and deepens SIRS by release toxins and increase of TNF-alpha.

Amine-chelated aryllithium reagents--structure and dynamics

Multinuclear NMR studies of five-membered-ring amine chelated aryllithium reagents 2-lithio-N,N-dimethylbenzylamine (1), the diethylamine and diisopropylamino analogues (2, 3), and the o-methoxy analogue (4), isotopically enriched in (6)Li and (15)N, have provided a detailed picture of the solution structures in ethereal solvents (usually in mixtures of THF and dimethyl ether, ether, and 2,5-dimethyltetrahydrofuran). The effect of cosolvents such as TMEDA, PMDTA, and HMPA has also been determined. All compounds are strongly chelated, and the chelation is not disrupted by these cosolvents. Reagents 1, 2, and 3 are dimeric in solvents containing a large fraction of THF. Below -120 degrees C, three chelation isomers of the dimers are detectable by NMR spectroscopy: one (A) with both nitrogens coordinated to one lithium of the dimer, and two (B and C) in which each lithium bears one chelating group. Dynamic NMR studies have provided rates and activation energies for the interconversion of the 1-A, 1-B, and 1-C isomers. They interconvert either by simple ring rotation, which interconverts B and C, or by amine decoordination (probably associative, DeltaG(++)(-93) = 8.5 kcal/mol), which can interconvert all of the isomers. The dimers of 1 are thermodynamically more stable than those of model systems such as phenyllithium, o-tolyllithium, or 2-isoamylphenyllithium (5, DeltaDeltaG > or = 3.3 kcal/mol). They are not detectably deaggregated by TMEDA or PMDTA, although HMPA causes partial deaggregation. The dimers are also more robust kinetically with rates of interaggregate exchange, measured by DNMR line shape analysis of the C-Li signal, orders of magnitude smaller than those of models (DeltaDeltaG(++) > or = 4.4 kcal/mol). Similarly, the mixed dimer of 1 and phenyllithium, 13, is kinetically more stable than the phenyllithium dimer by >2.2 kcal/mol. X-ray crystal structures of the TMEDA solvate of 1-A and the THF solvate of 3-B showed them to be dimeric and chelated in the solid state as well. Compound 4, which has a methoxy group ortho to the C-Li group, differs from the others in being only partially dimeric in THF, presumably for steric reasons. This compound is fully deaggregated by 1 equiv of HMPA. Excess HMPA leads to the formation of ca. 15% of a triple ion (4-T) in which both nitrogens appear to be chelated to the central lithium.

HBV-DNA level in blood serum as a predictor of good response to therapy with interferon-alpha-2b of patients with chronic hepatitis B

The prevalence of hepatitis B infection in population in Poland is low and averages 1-1.5%. However, it means that about 380,000 Poles constantly or temporarily replicate HBV. Chronic HBV infection is associated with increased risk of serious liver diseases and it is estimated that 25-40% of patients with chronic hepatitis B will die prematurely of cirrhosis or primary liver cancer. Up to the present, interferon-alpha (IFN-alpha), with low response rate between 25-55% and some limitations of therapy, has been the only available treatment for chronic hepatitis B. A favorable outcome of IFN-alpha therapy is associated with some prognostic factors, not accepted by all investigators, such as low level of HBV-DNA in serum. The aim of this study was to assess the efficacy of therapy with IFN-alpha 2b (Intron A), administered s.c. 5 MU x 3/week for 16 weeks, in 65 patients with chronic hepatitis B, divided into groups according to the baseline HBV-DNA level. Except for serum HBV-DNA level, there were no demographical and biochemical differences between all the treated groups. The patients were followed-up for 12 months. Sustained response (SR) to the therapy (defined as ALAT normalization, loss of detectable HBV-DNA, seroconversion HBeAg to anti-HBeAg and improvement in liver histology) was observed in 16 (57.14%) of patients in the group with HBVDNA level < 1000 pg/ml, in 6 (37.5%) with HBV-DNA level of 1001-3000 pg/ml, in 4 (28.57%) with HBV-DNA level of 3001-5000 pg/ml and only in 2 (28.57%) of patients in group with HBVDNA level > 5000 pg/ml. We conclude that IFN-alpha is particularly useful in therapy of patients with chronic hepatitis B with low levels of HBV-DNA. The baseline HBVDNA level < 1000 pg/ml in serum is the predictor of good response to IFN-alpha therapy.

[Drug interactions in practice]

As potential modulators of drug safety and effectiveness the compatibility and stability of drugs are important elements in drug prescription and drug administration to patients. According to various characteristics, important differences between areas of stationary hospital care and ambulatory care are evident. While the challenges in the ambulatory care setting have been focussed on dermatological topical medication, incompatibility assessment is a challenge for the physician and the pharmacist in a hospital setting. Particularly in intensive care patients often up to 20 different drugs are administered in only few infusion devices or through a limited number of parenteral infusion lines. Among the compounds most often incriminated to cause incompatibilities are furosemide, phenytoin, midazolam and diazepam when used as i.v. admixtures. In recent years new challenges arose in ambulatory care in the area of oncologic treatment. Cytotoxic drug therapy and supportive care therefore requires increasing attention in terms of incompatibility of ready to use combined drug admixtures. To prevent incompatibilities never more than one drug should be added, nutrition solutions should never be used as carrier solutions for drug administration, mixtures should not be stored and should be administered immediately after preparation. During the administration of unavoidable mixtures visible changes of the solutions should be carefully sought.

[Principles of evidence-based medicine; merits and pitfalls]

Historical background, main principles, methodology of evidence based medicine (EBM) and prospective randomized trials (incl. megatrials) are reviewed. EBM has a significant beneficial influence on medical activities as follows: improving efficacy of medical therapy, generation of new research trends, optimizing decision making in clinical settings of incomplete pathophysiological background, exploring new associations can be found beyond the individual clinician's scope, regular financial support of gradual, postgradual medical training, medical research and international scientific programs. Potential adverse influences related to EBM are: weakening position of individual (versus modus) patient-oriented approach in medical care, diminution of pathophysiology- (versus product-) oriented medical research, reevaluation of medical, scientific activity, interrelations between medical doctors and patients. Potential misuse of statistical methods in evaluation of megatrials is briefly discussed. A combination of benefits related to EBM and traditional elements of classical medical care, clinical research is needed to establish a more improved medical care for the individual patient.

Phase I clinical and pharmacokinetic study of perillyl alcohol administered four times a day

We conducted a phase I dose-escalation trial of perillyl alcohol (POH; NSC 641066) given p.o. on a continuous four times a day basis to characterize the maximum tolerated dose, toxicities, pharmacokinetic profile, and antitumor activity. Sixteen evaluable patients with advanced refractory malignancies were treated at the following doses: level 1 (L1), 800 mg/m2/dose; L2, 1200 mg/m2/dose; L3, 1600 mg/m2/dose. POH was formulated in soft gelatin capsules containing 250 mg of POH and 250 mg of soybean oil. The predominant toxicities seen were gastrointestinal (nausea, vomiting, satiety, and eructation), which were dose limiting. There appeared to be a dose-dependent increase in levels of the two main metabolites, perillic acid and dihydroperillic acid. No significant differences were seen whether the drug was taken with or without food. There was a trend toward decreasing metabolite levels on day 29 compared with days 1 and 2. Peak metabolite levels were seen 1-3 h post ingestion. Metabolite half-lives were approximately 2 h. Approximately 9% of the total dose was recovered in the urine in the first 24 h, the majority as perillic acid. Evidence of antitumor activity was seen in a patient with metastatic colorectal cancer who has an ongoing near-complete response of > 2 years duration. Several other patients were on study for > or = 6 months with stable disease. The maximum tolerated dose of POH given continuously four times a day was 1200 mg/m2/dose. Gastrointestinal toxicity was dose limiting, although significant interpatient variability in drug tolerance was seen.

[Two cases of malignant and benign systemic mastocytosis]

The authors give a short account about the clinical histories of two patients: one with malignant systemic mastocytosis resulting in acute myeloid leukaemia, the other with indolent systemic mastocytosis. A brief review is reported about the physiological and pathophysiological role of mastocyte system. Benign and malignant types, classification of mastocyte proliferation are detailed, several distinct characteristics of clinical appearance, main aspects of diagnosis, therapy and prognosis in patients with different forms of systemic mastocytosis are briefly discussed.

Current knowledge in the management of children and adolescents with sickle cell disease: Part 1, Physiological issues

This article reviews the current state of the knowledge in the management of children and adolescents with sickle cell disease (SCD). A thorough review of the literature concerning physiological issues including the clinical manifestations of SCD as well as current treatment modalities is included. Therapeutic management of health and illness for a child with SCD is discussed in relation to primary, secondary, and tertiary prevention. Recommendations for nursing practice and research are made.

Seroprevalence of Bartonella henselae in cats in Germany

Bartonella henselae and B. quintana infections in man are associated with various clinical manifestations including cat-scratch disease, bacillary angiomatosis and bacteraemia. While cats are the natural reservoir for B. henselae, the source of B. quintana is unclear. In this study, the sera of 713 cats from Germany were examined for the presence of antibodies against B. henselae, B. quintana or Afipia felis by an indirect immunofluorescence assay (IFA). Bartonella-specific antibody titres of > or =50 were found in 15.0% of the cats. There was substantial cross-reactivity among the various Bartonella antigens, although single sera showed high titres against B. henselae but not against B. quintana and vice versa. Antibodies against A. felis were not detected in any of these cats. Statistical analysis indicated that there is no correlation between Bartonella infections and the sex, age or breed of the cat or its hunting behavior. There was also no correlation between bartonella and toxoplasma infections in cats. However, whereas 16.8% of cats from northern Germany had B. quintana-specific antibodies, only 8.0% of cats from southern Germany were seropositive for B. quintana. No statistically significant difference was found for B. henselae. IFA-positive and IFA-negative sera were used for immunoblot analysis including B. henselae and B. quintana. Marked reactivity was observed with protein bands at 80, 76, 73, 65, 37, 33 and 15 kDa. The results of this study suggest that B. henselae, and possibly a B. quintana-related pathogen, but not A. felis, are common in cats in Germany, and that there are differences in the geographic distribution of bartonella infections in cats.

Intraarticular fentanyl compared with morphine for pain relief following arthroscopic knee surgery

PURPOSE

To compare the analgesia produced by comparable doses of intra-articular (IA) morphine and fentanyl.

METHODS

Sixty-nine healthy patients undergoing arthroscopic surgery received a standardized general anesthetic of 4 mg x kg(-1) thiopental and 2 microg x kg(-1) fentanyl followed by 2 mg x kg(-1) succinylcholine prior to tracheal intubation and controlled ventilation. Maintenance of anesthesia was achieved with N2O/O2 and isoflurane. At the conclusion of surgery intra-articular injection was: Group I (n=23) 50 microg fentanyl in 20 ml saline; Group II (n=24) 3 mg morphine in 20 ml saline; Group III (n=22) 20 ml saline. Pain scores at rest using a visual analogue scale were recorded by a separate blinded observer at one, two, four, and eight hours postoperatively.

RESULTS

Pain scores at one, two, four, and eight hours were 36, 26.3, 20.9, and 12.8 vs 35.8, 33.8, 28.8, and 21.9 vs 70.5, 57.7, 58.4, and 53.6 for the IA-fentanyl, IA-morphine, and control groups respectively. Pain scores were greater at all times for Group III. Pain scores for Groups I and II were similar at one hour, but thereafter were less (P < 0.001) for the IA-fentanyl group.

CONCLUSION

Better postoperative analgesia was achieved with 50 microg intraarticular fentanyl than with 3 mg intraarticular morphine.

Isolation and identification by partial sequencing of the 18S ribosomal gene of free-living amoebae from necrotic tissue of Basilliscus plumifrons (Sauria: Iguanidae)

A 3-year-old Basiliscus plumifrons developed a necrotic lesion on the tail resulting from nodules of unknown etiology. Investigation of necrotic tissue revealed several gram-negative bacteria as well as three different species of free-living amoebae. The amoebae were identified by morphological characters as belonging to the genera Acanthamoeba, Echinamoeba, and Naegleria, respectively. Partial sequencing of the 18S ribosomal gene was performed for reliable systematic determination. Two of the isolates showed thermotolerance. No isolate was growable in conventional liquid media, but the Acanthamoeba strain readily grew on a human cell line (HEp2). It remains unclear whether the amoebae fed on the coexisting bacteria or on host tissue.

A pilot study of melphalan, tumor necrosis factor-alpha and 41.8 degrees C whole-body hyperthermia

PURPOSE

To evaluate the feasibilitv of sequencing (based on preclinical modeling) tumor necrosis factor-a (TNF) at two dose levels with melphalan (L-PAM) and 41.8 C whole-body hyperthermia (WBH) for 60 min.

PATIENTS AND METHODS

Nine patients with refractory cancer were treated from October 1995 to June 1997. The study encompassed a total of 20 trimodality treatment courses. Three patients were treated at TNF dose level I (50 microg/m2) and six patients were treated at TNF dose level II (100 microg/m2). TNF was delivered as a 24-h intravenous infusion, 48 h prior to the combination of L-PAM and WBH; L-PAM was given over 10 min at target temperature at a dose of 17.5 mg/ m2 based on a previous phase I WBH/L-PAM trial. WBH was administered with an Aquatherm radiant heat device.

RESULTS

Myelosuppression was the major toxicity associated with therapy, but there were no instances of bleeding or neutropenic fevers. Grade 3 thrombocytopenia was seen with 15% of treatments. Regarding absolute neutrophil count, 15% of treatments were associated with grade 3 toxicity, and 45% with grade 4 toxicity, and regarding white blood cell count, 50% of treatments were associated with grade 3 toxicity and 10% with grade 4 toxicity. The myelosuppression observed was equivalent to that seen in our earlier phase I study of WBH and L-PAM (without TNF). Only mild toxicities (grade 1 or 2) were associated with TNF; these were seen with <25% of treatments and included nausea, vomiting, diarrhea, fevers, and headache. There were no instances of hypotension. There was no relationship between toxicities observed and the two TNF dose levels. Mild WBH toxicities were seen with less than 15% of treatments; these included nausea, vomiting, and herpes simplex I. Responses included two complete remissions (malignant melanoma, TNF dose level I; breast cancer, TNF dose level II), and two disease stabilizations (both malignant melanoma, TNF dose level I).

CONCLUSION

We conclude that the combination of TNF, L-PAM, and WBH is well tolerated at the dose levels studied. The clinical results justify further clinical investigation for this trimodality treatment approach.