Role of five platelet membrane glycoprotein polymorphisms in branch retinal vein occlusion.

To determine whether polymorphisms of platelet surface glycoprotein associated with arterial thrombosis are risk factors for branch retinal vein occlusion. A case-control study in which 69 patients with branch retinal vein occlusion and 147 controls who attended the eye clinic for nonvascular complications participated. DNA was extracted from whole blood and analyzed for genotyping of platelet glycoprotein polymorphisms by polymerase chain reactions and specific restricted enzymes. No relationship was found between the four platelet glycoprotein polymorphisms i.e. GPIa C807T, VNTR and Kozak of glycoprotein Ibalpha, the HPA-1 of glycoprotein IIIa and the occurrence of branch retinal vein occlusion. The HPA-2 polymorphism was found in 18 out 60 (30%) patients with branch retinal vein occlusion in comparison with 27 out 142 (19%) of controls, with an estimated odds ratio of 1.8 (95% confidence interval, 0.91-3.65). The four platelet glycoprotein polymorphisms are not risk factors for branch retinal vein occlusion and therefore it seems unnecessary to screen those patients for it. A larger study is required, however, to determine whether HPA-2 is a novel risk factor for branch retinal vein occlusion.     

Searching for the Favorable Donor Site for Fat Injection: In Vivo Study Using the Nude Mice Model

BACKGROUND: The use of suctioned fat grafts for correction of soft tissue defects is a widespread procedure in esthetic and reconstructive surgery. The main disadvantage of this simple and sensible procedure is the unpredictable absorption rate of the fat graft. A lot of research has been performed aiming for enhancement of the take of the fat grafts. OBJECTIVE: Our study was performed to find if there is any favorable donor site for fat harvesting. METHODS: This in vivo experiment using the nude mice model enables the study of the long-term survival of human fat in an animal model. The fat was harvested from three donor areas: the thigh, abdomen, and breast of a 48-year-old woman who came for an elective esthetic procedure. After centrifugation, 1 cc of fat was injected subcutaneously into the scalp of the nude mouse. There were 15 mice in each of the three groups, according to the selected donor sites. The animals were sacrificed 16 weeks after the procedure. The extracted fat was evaluated in terms of weight, volume, and six histologic parameters: integrity, vascularization, cyst formation, fibrosis, necrosis, and inflammation. RESULTS: This study could not find any statistically significant differences between the three investigated donor sites in the evaluated parameters. CONCLUSION: On the basis of this study, there is no favorable area for harvesting fat grafts. The donor site can be chosen according to the preference of the surgeon and the patient.     

Functional signatures of protective antiviral T-cell immunity in human virus infections

Summary: The most common human viruses have different abilities to establish persistent chronic infection. Virus‐specific T‐cell responses are critical in the control of virus replication and in the prevention of disease in chronic infection. A large number of phenotypic markers and a series of functions have been used to characterize virus‐specific CD4⁺ and CD8⁺ T‐cell responses, and these studies have shown great phenotypic and functional heterogeneity of the T‐cell responses against different viruses. The heterogeneity of the T‐cell response has been proposed to be specific to each virus. However, over the past 2 years, several studies have provided evidence that the phenotypic and functional heterogeneity of CD4⁺ and CD8⁺ T‐cell responses is predominantly regulated by the levels of antigen load. The levels of antigen load modulate the phenotypic and functional patterns of the T‐cell response within the same virus infection. Furthermore, the functional characterization of virus‐specific CD4⁺ and CD8⁺ T‐cell responses has identified signatures of protective antiviral immunity. Polyfunctional, i.e. interleukin‐2 and interferon‐γ (IFN‐γ) secretion and proliferation, and not monofunctional, i.e. IFN‐γ secretion, CD4⁺ and CD8⁺ T‐cell responses represent correlates of protective antiviral immunity in chronic virus infections.     

Acute radiation reactions in oral and pharyngeal mucosa: tolerable levels in altered fractionation schedules.

PURPOSE:To investigate whether a predictive estimate can be obtained for a 'tolerance level' of acute oral and pharyngeal mucosal reactions in patients receiving head and neck radiotherapy, using an objective set of dose and time data. MATERIALS AND METHODS:Several dozen radiotherapy schedules for treating head and neck cancer have been reviewed, together with published estimates of whether they were tolerated or (in a number of schedules) not. Those closest to the borderline were given detailed analysis. Total doses and biologically effective doses (BED or ERD) were calculated for a range of starting times of cellular repopulation and rates of daily proliferation. Starting times of proliferation from 5 to 10 days and daily cellular doubling rates of 1-3 days were considered. The standard published form of BED with its linear overall time factor was used: BED=nd(1 + d/(alpha/beta) - Ln2(T - T(k))/alpha T(p) (see text for parameters). RESULTS: A clear progression from acceptable to intolerable mucosal reactions was found, which correlated with total biologically effective dose (BED in our published modeling), for all the head and neck cancer radiotherapy schedules available for study, when ranked into categories of 'intolerable' or 'tolerable'. A review of published mechanisms for mucosal reactions suggested that practical schedules used for treatment caused stimulated compensatory proliferation to start at about 7 days. The starting time of compensatory proliferation had little predictive value in our listing, so we chose the starting time of 7 days. Very short and very long daily doubling rates also had little reliability, so we suggest choosing a doubling time of 2.5 days as a datum. With these parameters a 'tolerance zone of uncertainty' could be identified which predicted acute-reaction acceptability or not of a schedule within a range of about 2-10 Gy in total BED. If concurrent chemoradiotherapy is used, our provisional suggestion is that this zone should be reduced by up to roughly 3-5 Gy10 in BED, with a request for further evidence. CONCLUSIONS:It is suggested that total BED should be used, as specified above. Parameters of alpha=0.35 Gy-(1), alpha/beta=10 Gy, Tk=7 days and Tp=2.5 days are suggested. The 'acute/ tolerance zone' then turns out to be 59-61 Gy10 for radiation-only treatments. Further information about the decrement caused by concurrent head-and-neck cancer chemoradiotherapy, possibly 3-5 Gy10, is required.     

Role perceptions in a community mental health setting

The increasing trend of utilizing nonprofessional personnel in community mental health has led to considerable controversy. It is suggested that studies comparing the relative competence and efficacy of professional therapists to that of nonprofessional therapists may be counterproductive and in need of augmentation. The present study employed a role perception procedure in which members of three different randomly chosen groups (11 professional therapists, 11 nonprofessional therapists, and 11 children-clients) from a community mental health program were asked to rank various aspects of the therapeutic relationship in order of importance to the children-clients' improvement. It was hypothesized that (a) due to their relatively low self-concept, nonprofessionals would underestimate their own role importance in comparison to that of the professionals; (b) professionals would overestimate their own role importance; and (c) children would selectively value certain aspects of each role without preferring one over the other. The last two hypotheses were supported, but the first hypothesis was not: nonprofessionals, in fact, showed the highest level of overestimation of their own role importance. A further analysis of the data showed that inexperienced nonprofessionals did not overestimate their own role performance. This suggested specific training procedures for nonprofessionals.     

Serum anti-Mullerian hormone levels during controlled ovarian hyperstimulation in women with polycystic ovaries with and without hyperandrogenism

BACKGROUND: Anti-Mullerian hormone (AMH) is expressed in pre- and small-antral follicles. High serum levels are found in women with polycystic ovaries (PCO), accordant with their increased content of small follicles. To evaluate the relationship between AMH, folliculogenesis and hyperandrogenism, we compared serum AMH levels between women with PCO with and without hyperandrogenism and normal controls during controlled ovarian hyperstimulation (COH). METHODS: Nineteen women with PCO and hyperandrogenism (group A), 10 women with PCO but no hyperandrogenism (group B) and 23 ovulatory women with normal ovarian morphology (group C, controls) underwent COH with the long protocol. Serum levels of AMH, estradiol, androstenedione and follicular tracking were determined before gonadotropins treatment (day 0) and every 2-4 days up to the day of HCG administration. RESULTS: AMH levels declined gradually throughout COH in the three groups, but remained higher in groups A and B compared with the controls. Significantly higher levels were found in group A compared with group B, despite comparable numbers of small follicles. Multiple regression analysis revealed that both the number of small follicles and serum androgens were correlated to AMH. CONCLUSIONS: Women with PCO have higher serum AMH levels during COH than controls. Hyperandrogenism is associated with an additional increase in AMH. It is conceivable that hyperandrogenism may reflect more severe disruption of folliculogenesis in women with PCO or may affect AMH secretion.     

Effect of leukocyte hydrolases on bacteria

The bactericidal and bacteriolytic effects of lysolecithin (LL) and egg-white lysozyme (LYZ) on Staph. aureus and group A streptococci and the solubilization of phospholipids from the bacterial membranes by these agents was studied. Low concentrations of lysolecithin (1--10 microgrames/ml) are highly bactericidal for Steph. aureus and group A streptococci, but induce neither bacteriolysis nor solubilization of a substantial amount of membrane phospholipids. On the other hand, while LL at greater than 50 micrograms/ml causes substantial lipid release, a combination of LL and LYZ is absolutely needed to solubilize lipids from streptococci. This combination is, however, not bacteriolytic for this microrganism. The solubilization of lipids from staphylococci by LL is much faster than that induced in streptococci by LL + LYZ. The solubilization of the bulk of membrane lipids from staphylococci can also be achieved by Triton X-100 and by sodium lauryl sulfate and from group A streptococci by Triton X-100 plus LYZ. A variety of other detergents (e.g., Cetavlon, sodium taurocholate, cetyl pyrdinium chloride) have no lipid-releasing properties even in the presence of LYZ. The release of lipids by LYZ (in the presence of LL) from group A streptococci is related to its enzymatic activity, on a still unknown substrate, but not to its cationic nature as this muramidase cannot be replaced by a variety of cation substances (histone, polylysin, leukocyte cationic proteins, polymyxin B, and spermidine). The release of lipids from staphylococci by LL is not inhibited by a variety of anionic and cationic polyelectrocytes (heparin, liquoid, chondroitin sulfate, DNA histone, and polylysine) which markedly inhibit the release of lipids from group A streptococci by LL and LYZ. Streptococci that had been cultivated in the presence of subinhibitory concentrations of penicillin G lose their membrane phospholipids to a larger extent and by much smaller concentrations of LL and LYZ, as compared to controls, suggesting that the interference with the synthesis of the peptidoglycan increases the accessibility of the cell membrane to the lipid-releasing agents. The mechanism by which LL collaborates with LYZ in lipid release is still not known. The possible role of bacterial lipids and lyso compounds in the control of bacterial survival in inflammatory sites is briefly discussed.     

Carboxy-terminal peptides from the B subunit of Shiga toxin induce a local and parenteral protective effect

Two synthetic peptides corresponding to overlapping sequences from the C-terminus of the B chain of Shiga toxin were prepared and characterized. These peptides consisted of residues 54-67 and 57-67 in the protein sequence. This region coincides with the major peak of surface area residues, as predicted from a computer-derived plot. For the purpose of immunization, the peptides were either conjugated with a protein or a synthetic carrier, or were polymerized. Polyclonal antibodies against these peptides derivatives, induced in rabbits, recognized the homologous peptides and cross-reacted with the intact toxin. These antibodies were capable of neutralizing the various biological activities of the toxin, namely the cytotoxic, enterotoxic and neurotoxic activities. Active immunization of mice with the peptide derivatives protected them from the lethal effect of the toxin. Moreover, oral immunization of rats led to inhibition of fluid secretion in ligated ileal loops into which toxin was injected. This effect was paralleled by the induction of high levels of specific anti-peptide IgA antibodies in the serum after bile duct ligation.     

Nutrient Intake following Vertical Banded Gastroplasty or Gastric Bypass

Background: This study explored eating habits, nutrient intake, and blood vitamin and mineral levels to determine whether severely obese subjects (BMI 40-50 kg m⁻²) post-vertical banded gastroplasty (VBG) or gastric bypass Roux-en-Y (GBR) are at risk of developing compounded under-nutrition. Methods: A dietary follow-up of 36 VBG and 19 GBR was maintained for 18 months via 7-day food intake diaries and 24-h recalls. Food intake was analysed for energy and nutrient composition and for its relative amount to recommended dietary allowances (RDA). Results: Weight loss was greatest during the first 6 months, continued at a slower rate for the next 6 months, nearly ceasing thereafter. The results following GBR were not substantially different from those following VBG 18 months postoperatively. The median weight loss at 1 year postoperatively was 48, 46, 48 and 36 kg; expressed as residual excess body weight: 0.2, 16, 13 and 22% for GBR Men, Women, VBG Men, Women, respectively. According to the classification proposed by Reinhold, all subjects achieved excellent treatment outcomes 18 months postoperatively. Despite the relatively low reported energy intake (20-50% below RDA), no correlation was found between rate of weight loss and energy intake at 6 months postoperatively. The intake of most vitamins and minerals was below 50% of RDA during the 18 months follow-up. The increase in energy intake did not improve the level of the nonenergy-contributing nutrients. Compliance to multivitamin and mineral supplement intake deteriorated with time. Conclusion: The low to within-normal range of blood vitamin and mineral levels 12 months postoperatively suggests the slow development of subclinical nutritional deficiency which could jeopardize the subjects' long-term health status.