Growth hormone reduces mortality and bacterial translocation in irradiated rats

Growth hormone stimulates the growth of intestinal mucosa and may reduce the severity of injury caused by radiation. Male Wistar rats underwent abdominal irradiation (12 Gy) and were treated with either human growth hormone (hGH) or saline, and sacrificed at day 4 or 7 post-irradiation. Bacterial translocation, and the ileal mucosal thickness, proliferation, and disaccharidase activity were assessed. Mortality was 65% in irradiated animals, whereas hGH caused a decrement (29%, p < 0.05). Bacterial translocation was also reduced by hGH (p < 0.05). Treating irradiated rats with hGH prevented body weight loss (p < 0.05). Mucosal thickness increased faster in irradiated hGH-treated animals. The proliferative index showed an increment in hGH-treated animals (p < 0.05). Giving hGH to irradiated rats prevented decrease in sucrose activity, and increment in lactase activity. In conclusion, giving hGH to irradiated rats promotes the adaptative process of the intestine and acute radiation-related negative effects, including mortality, bacterial translocation, and weight loss.

Clinical significance of viral load in the diagnosis of cytomegalovirus disease after liver transplantation

In a cohort of 43 liver transplant recipients who did not receive antiviral prophylaxis, qualitative and quantitative polymerase chain reactions (PCRs) from peripheral blood were prospectively compared to determine their value in the diagnosis of established cytomegalovirus (CMV) disease and for the early detection of CMV replication as a marker for preemptive antiviral therapy. Using a cutoff of 7000 copies of CMV DNA per sample, the specificity and positive predictive values of qualitative PCR for the diagnosis of established CMV disease increased from 33% to 89% and from 54% to 82%, respectively, without reducing the 100% sensitivity and negative predictive value. By contrast, quantification of viral load provided no additional advantage to qualitative PCR for the early diagnosis of CMV infection before development of disease.

Attitudes and issues in treating Latino patients with type 2 diabetes: views of healthcare providers

The purpose of this study was to explore the concerns of Latino patients with Type 2 diabetes. Focus groups were conducted with healthcare practitioners to chart their perceptions of the issues faced by their Latino patients. One group consisted of professionals working among Mexican American clients in an inner-city clinic; another group was held at an inner-city hospital serving mostly Puerto Rican Americans; and a third group involved providers practicing with more affluent, suburban Mexican Americans. Practitioners agreed that communication with patients was hindered by low reading levels, lack of proficiency in English, and an excessive respect for physicians. Emotional barriers to adequate treatment were often more important than financial concerns, even among low-income patients. Fear of insulin therapy was expressed in Hispanic communities, and folk remedies were commonly used. Because family needs were considered most important, adhering to a treatment regimen might be viewed as self-indulgent. Yet families provided valuable reinforcement and emotional support. Important questions facing Latinos with diabetes were effectively identified using focus groups of healthcare providers.

An evaluation of a chest pain diagnostic protocol to exclude acute cardiac ischemia in the emergency department

BACKGROUND

Although accelerated diagnostic protocols are being increasingly used in emergency departments to diagnose acute cardiac ischemia, there have been no prospective evaluations of a chest pain diagnostic protocol with serial determinations of creatine kinase MB isoenzyme and mandatory exercise electrocardiography (ExECG).

METHODS

Prospective cross-sectional study in which chest pain protocol results were compared with final (reference) diagnoses of acute cardiac ischemia (including acute myocardial infarction and unstable angina). Patients in need of hospital admission but at low probability (by a validated algorithm) for acute myocardial infarction were examined for exclusions: known coronary artery disease, cardiac complications, severe comorbidities, or inability to perform exercise testing. A 12-hour diagnostic protocol included serial measurements of creatine kinase MB, ECG, and clinical assessments followed by ExECG for those with negative initial serial testing. Reference diagnoses were established during hospitalization and diagnostic accuracy was assessed.

RESULTS

The study group of 317 patients was 54% male and 65% black, and had a mean age of 46.6 years; 9.5% had a final diagnosis of acute cardiac ischemia. For this diagnosis, the protocol had a sensitivity of 90.0% (95% confidence interval, 72.3%-97.4%); specificity, 50.5% (95% confidence interval, 44.6%-56.4%); positive predictive value, 16.0%; and negative predictive value, 98.0%. Creatine kinase MB, serial ECGs, and ExECG each made a contribution to improved sensitivity and accuracy, whereas clinical reassessments were less discriminating, as indicated by protocol's receiver operating characteristic curve.

CONCLUSIONS

A chest pain diagnostic protocol achieved high sensitivity and improved specificity over the standard emergency department workup. There were no adverse advents associated with early ExECG.

Protein-primed DNA replication: a transition between two modes of priming by a unique DNA polymerase

Phage phi29 from Bacillus subtilis is a paradigm of the protein-primed replication mechanism, in which a single-subunit DNA polymerase is involved in both the specific protein-primed initiation step and normal DNA elongation. To start phi29 DNA replication, the viral DNA polymerase must interact with a free molecule of the viral terminal protein (TP), to prime DNA synthesis once at each phi29 DNA end. The results shown in this paper demonstrate that the DNA polymerase-primer TP heterodimer is not dissociated immediately after initiation. On the contrary, there is a transition stage in which the DNA polymerase synthesizes a five nucleotide-long DNA molecule while complexed with the primer TP, undergoes some structural change during replication of nucleotides 6-9, and finally dissociates from the primer protein when nucleotide 10 is inserted onto the nascent DNA chain. This behaviour probably reflects the polymerase requirement for a DNA primer of a minimum length to efficiently catalyze DNA elongation. The significance of such a limiting transition stage is supported by the finding of abortive replication products consisting of the primer TP linked up to eight nucleotides, detected during in vitro replication of phi29 TP-DNA particularly under conditions that decrease the strand-displacement capacity of phi29 DNA polymerase.

Effect of 17 beta-estradiol on chondrocyte membrane fluidity and phospholipid metabolism is membrane-specific, sex-specific, and cell maturation-dependent

In this study we examined the hypothesis that 17 beta-estradiol exerts both rapid and direct, nongenomic effects of cells in the endochondral pathway. To do this, we used a cell culture model in which chondrocytes at two distinct stages of cell maturation are isolated from the costochondral cartilage of male and female rats, and examined the short-term effect of 17 alpha- and 17 beta-estradiol on [14C]arachidonic acid turnover in the cell layer and phospholipase A2 specific activity in plasma membranes and extracellular matrix vesicles isolated from similarly prepared cultures. In addition, the effect of 17 alpha- and 17 beta-estradiol on plasma membrane and matrix vesicle membrane fluidity was assessed. The effect of hormone on arachidonic acid turnover was rapid, time- and concentration-dependent, stereo-specific, and cell maturation-specific. Only resting zone cells from female rats were affected, and only 17 beta-estradiol elicited a response. Similarly, only female rat resting zone chondrocytes exhibited a change in phospholipase A2 activity after a 24 h exposure to hormone, causing an increase in enzyme activity in the matrix vesicles, but not plasma membranes. When isolated membranes were incubated directly with hormone, membrane fluidity was decreased in both plasma membranes and matrix vesicles isolated from female rat resting zone chondrocyte cultures. This nongenomic effect was dose-dependent and stereo-specific and differentially expressed in the two membrane fractions with respect to time course and magnitude of response. These results support the hypothesis that 17 beta-estradiol has a rapid action on chondrocyte membrane lipid metabolism and suggest that specific membrane components, characteristic of a particular sex and state of cell maturation, are involved in the nongenomic effects of this sex hormone on isolated matrix vesicles and plasma membranes.

Hypersensitivity to carrot associated with specific IgE to grass and tree pollens

This study deals with a 34-year-old female cook with no previous history of atopy, who was studied because of allergic rhinoconjunctivitis and contact urticaria in both hands associated with severe itching when she handled raw carrot. The patient had had anaphylactic episodes after accidental ingestion of raw carrots, but she tolerated cooked carrots. Skin prick tests with carrot, celery, and olive, and birch, grass, and mugwort pollens were positive. Total IgE was 411 UI/ml. Specific IgE to olive, grass, and weed pollens were 10.92, 6.17, and 2.4 AU/ml, respectively. The histamine release test was positive for carrot, celery, celeriac, and olive pollen up to a dilution of 1/10(6). Immunoblot of raw carrot showed a single IgE-binding 18-kDa band. IgE reactivity for raw carrot immunoblot was completely inhibited by carrot and by celery, but not by olive or grass pollens. Specific IgE to olive pollen was not inhibited by carrot. The existence of monosensitization to an 18-kDa protein in carrot and specific IgE to olive pollen has not been reported in the celery-carrot-mugwort-spice syndrome.

The response of highly productive rabbits to dietary sulphur amino acid content for reproduction and growth

This study investigated the sulphur amino acid (SAA) requirements of rabbits. Five diets, containing 0.48-0.72% crude SAA, were formulated by supplementing a basal diet with DL-methionine. The apparent methionine digestibility (%) was 71.4 +/- 1.1 in the basal diet and 102.9 +/- 0.9 for DL-methionine, as estimated by the difference method. Feeding trials were carried out using 370 rabbit does and 1 195 weanling rabbits slaughtered at 2-2.1 kg body weight. Milk production was measured in 80 lactations. Carcass traits were determined in 125 rabbits. The dietary SAA content affected several productive traits, such as milk production, parturition interval, growth rate, carcass quality and feed efficiency. When the diets were compared using orthogonal contrasts, a minimum requirement of 0.54% crude or 0.40% digestible SAA was determined. Further responses in performance were observed, however, when the data were analysed by regression methods. The values of crude and digestible SAA for optimal production were, respectively, 0.63 and 0.49% (rabbit does) and, at least, 0.72 and 0.58% (growing rabbits).

A tactile sensory system of Myxococcus xanthus involves an extracellular NAD(P)(+)-containing protein

CsgA is a cell surface protein that plays an essential role in tactile responses during Myxococcus xanthus fruiting body formation by producing the morphogenic C-signal. The primary amino acid sequence of CsgA exhibits homology with members of the short-chain alcohol dehydrogenase (SCAD) family and several lines of evidence suggest that NAD(P)+ binding is essential for biological activity. First, the predicted CsgA secondary structure based on the 3 alpha/20 beta-hydroxysteroid dehydrogenase crystal structure suggests that the amino-terminal portion of the protein contains an NAD(P)+ binding pocket. Second, strains with csgA alleles encoding amino acid substitutions T6A and R10A in the NAD(P)+ binding pocket failed to develop. Third, exogenous MalE-CsgA rescues csgA development, whereas MalE-CsgA with the amino acid substitution CsgA T6A does not. Finally, csgA spore yield increased approximately 20% when containing 100 nM of MalE-CsgA was supplemented with 10 microM of NAD+ or NADP+. Conversely, 10 microM of NADH or NADPH delayed development for approximately 24 hr and depressed spore levels approximately 10%. Together, these results argue that NAD(P)+ binding is critical for C-signaling. S135 and K155 are conserved amino acids in the catalytic domain of SCAD members. Strains with csgA alleles encoding the amino acid substitutions S135T or K155R failed to develop. Furthermore, a MalE-CsgA protein containing CsgA S135T was not able to restore development to csgA cells. In conclusion, amino acids conserved in the coenzyme binding pocket and catalytic site are essential for C-signaling.

Photorefractive keratectomy for myopic astigmatism using the emphasis erodible mask. Spanish User Group

Photorefractive keratectomy (PRK) using the Summit emphasis erodible mask was performed on 229 eyes with myopic astigmatism. To analyze the efficacy and safety of the method, we evaluated the following: spectacle corrected visual acuity and refractive error as parameters of efficacy; corneal clarity, decentration of the ablation zone and complications as parameters of safety. Despite the short follow up (the longest was 12 months) our results show that the emphasis erodible mask appears to be an effective surgical method for correcting myopic astigmatism. However, we found a great number of complications and subjective symptoms that worsened the visual outcome. We conclude that the emphasis erodible mask has satisfactory efficacy but unsatisfactory safety.

Coping with ambiguity in multi-ethnic children of alcoholics

Visual field dependence in 292 multi-ethnic adult children of alcoholics (ACAs) and nonalcoholics (NACAs) was assessed, using the Hidden Figures Test (Ekstrom, French, & Harmon, 1976). There were no differences among ethnic groups, but ACAs achieved a significantly lower percentage of correct answers and more incorrect answers and attempted more questions relative to NACAs. These findings suggest that ACAs' visuospatial deficits are not related to ethnic and cultural factors.

Sarcosporidian infection in pigs in Uruguay

Examination of enzymatic digests of samples of the crux diaphragm obtained at abbatoirs in Montevideo, Uruguay, indicated that 57.2% of 269 pigs weighing 90-140 kg were infected with Sarcocystis sp. The morphology of sarcocystis in H & E stained sections indicated that they were Sarcocystis miescheriana.

Spontaneous gangrenous myositis induced by Streptococcus pyogenes: case report and review of the literature

A 54-year-old man presented with gangrenous myositis caused by Streptococcus pyogenes. A review of the literature disclosed 10 similar cases. Their presenting manifestations were spontaneously occurring, localized, excruciating pain; mottling suggestive of ischemic changes; and signs of sepsis. The duration of illness ranged from two to six days, and the outcome was uniformly fatal. This rare but distinct entity resembles clostridial myonecrosis except that it lasts slightly longer and does not involve gaseous crepitus. A definitive diagnosis of myonecrosi scan be established by surgical exploration; early, radical debridement plus penicillin therapy should be undertaken after diagnosis in an attempt to alter the usual devastating outcome.