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Augmentation of the alveolar ridge to facilitate implant placement in a single tooth extraction site or a completely edentulous arch is currently a well-accepted and routinely performed therapeutic procedure. This article describes a method for augmenting extraction sites and ridges, without primary closure or the use of barrier membranes over bone grafts. The technique retains or enhances gingival architecture while creating bone for placement of an implant in the most optimal position. The tooth is extracted, demineralized freeze-dried bone allograft or another augmentation material of choice is placed, and a provisional mucoadhesion partial denture is delivered. When the implant is uncovered and the healing abutment is placed, a flap design is utilized to create papillae and proper labial contour. The learning objective is familiarity with this technique, which is particularly useful for maxillary anterior implant placement. A case report is used to document the clinical procedure.

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This study evaluates the effectiveness of subgingival scaling and root planing with longer shank, thinner blade, rigid curets compared to the standard rigid Gracey curet. A total of 35 non-molar teeth from 7 patients provided 140 root surfaces for evaluation; 52 root surfaces were instrumented with the rigid longer shank curets; 52 with the standard rigid Gracey curets; and 36 provided untreated controls. A bilateral matched design was utilized where contralateral teeth in the same arch were instrumented. Instrumentation was standardized at 15 minutes per tooth. Both scaled and unscaled teeth were extracted immediately after the experimental procedures. They were viewed under a stereomicroscope with a 0.10 mm grid to assess the percent of surface covered by calculus and unaltered cementum. The curet efficiency was also evaluated. The results indicated a significant treatment effect compared to the controls in relation to the percentage of residual calculus and curet efficiency. However, there was no significant difference between the rigid longer shank and standard rigid Gracey curets. There was a difference noted when tooth surfaces were evaluated. Mesial tooth surfaces had the least remaining calculus and demonstrated the best curet efficiency.

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The presence of tubulin throughout what appears to be sperm penetration tunnels of in vivo fertilized rabbit oocytes was demonstrated by both immunofluorescence and transmission electron microscopy, using fluorescein and peroxidase-labeled antibodies, respectively. In approximately half the fertilized oocytes examined, intact microtubules were found at the point of entry of the spermatozoon into the zona pellucida, while amorphous deposits were found throughout the remainder of the tunnel, starting at the point of entry into the matrix of the corona radiata cell layer, and continuing to the perivitelline space. These continuous deposits of tubulin suggest that, in the rabbit, acrosomal microtubule-like structures may perform a role in mammalian fertilization, possibly as an enzyme binding or delivery system, although other functions are possible. No deposition of actin was detectable in these tunnels.

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A study was conducted to assess the feasibility of substituting diazepam for pentobarbital and phenobarbital in sedative-hypnotic tolerance testing and withdrawal of tolerant patients. Nineteen patients potentially dependent on sedative-hypnotics were tolerance tested with either diazepam or pentobarbital and, if tolerant, were withdrawn with diazepam or phenobarbital, respectively. Seventy-eight subjects previously described in the literature with drug dependencies similar to the diazepam and barbiturate groups provided a basis for comparing the diazepam group to untreated patients to determine whether diazepam was able to prevent abstinence symptoms. Withdrawal was successfully completed in all patients. The expected and observed incidence of seizures, delirium, and minor withdrawal for the barbiturate group and seizures and delirium for the diazepam group did not differ significantly, although a large type II error compromised these conclusions. A significant difference was seen between the observed and expected incidence of minor withdrawal symptoms in the diazepam-withdrawn patients.

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The use of thrombolytic agents for clotting disorders as compared with standard anticoagulant therapy is reviewed. The resolution rates of pulmonary emboli (PE) were examined in a comparison of streptokinase, urokinase, and heparin therapy in several studies. The effectiveness of streptokinase therapy was compared to heparin treatment of deep vein thrombosis (DVT) as well. In addition, studies on the use of thrombolytic agents for acute myocardial infarction (AMI) are reviewed. Clinical studies show that although streptokinase and urokinase promote more rapid resolution of PE and DVT (as determined by perfusion lung scans, angiography, and venography), superiority over conventional treatment has not been established. The disadvantages include greater cost and more frequent bleeding episodes than anticoagulant therapy. The studies of thrombolytic agents for AMI did not find significant beneficial effects on the mortality rates. It is recommended that thrombolytic agents not be used routinely for the treatment of PE, DVT, or AMI.

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Pronase-resistant low molecular weight stimulators for the activation of proacrosin to acrosin were found in rhesus monkey oviduct fluid collected before, during and after ovulation, but the presence of high concentrations of acrosin inhibitors before and after ovulation partly masked the stimulation in unfractionated fluid. This low molecular weight fraction of oviduct fluid had no detectable esterase or amidase activity by itself, and the stimulating factors were sensitive to digestion by hyaluronidase and chondroitin ABC lyase and were presumed to be glycosaminoglycans. Heparin and hyaluronic acid had similar effects. The presence of soluble glycosaminoglycans at the site of fertilization suggests that they may have a role in capacitation and fertilization.

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Immunofluorescence and electron microscopy were used to demonstrate the presence of tubulin and microtubule-like structures in rabbit and rhesus monkey sperm acrosomes. The distribution of tubulin within the acrosome appeared similar to the distribution of proteolytic activity, suggesting an association of proteinase with these structures. Electron microscopy of rhesus monkey sperm incubated in vitro demonstrated a progressive condensation of the acrosomal matrix into microtubule-like structure. A system of this type could explain the linear patterns of silver-proteinate staining in the pentration tunnel through the zona pellucida.

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Lipid accumulation is a hallmark of corpus luteum regression and we characterized lipids stored in rat corpora lutea of pregnancy between days 21 and 24 post coitum, the period of luteolysis. A 10-fold rise in lutein triglyceride concentrations occurred between days 21 and 24, which represented the major alteration in luteal lipid metabolism during luteolysis, coinciding with the appearance of numerous lipid droplets in the luteal cells. The fatty acid composition of luteal triglycerides was altered between days 20 and 23 in a pattern consistent with the influx of blood triglyceride fatty acids. No evidence for increased de novo fatty acid synthesis by luteal tissue between days 21 and 24 post coitum was obtained using in vitro methods. [14C]Acetate incorporation into lipids declined between days 16 and 24 and label was preferentially introduced into long chain polyunsaturated fatty acids. Rates of tritium incorporation into fatty acids from tritiated water were relatively low. [14C]Glucose was predominantly incorporated into the glycerol moiety of luteal lipids and incorporation of label into this fraction was augmented between days 21 and 23 post coitum. The incorporation of [14C]palmitate into triglycerides of luteal tissue during in vitro incubation also increased between days 21 and 23. In vitro lactate production, [14C]glucose oxidation, and [14C-palmitate oxidation to 14CO2 increased significantly during this time. We conclude that specific biochemical alterations occur in regressing corpora facilitating uptake and storage of blood glyceride fatty acids as triglycerides. The physiological significance of this triglyceride accumulation remains to be elucidated.

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Uteroglobin was measured under various hormonal conditions: pregnancy, pseudopregnancy, pseudopregnancy with exogenous progesterone, pseudopregnancy with exogenous 20alpha-hydroxyprogesterone, ovariectomy with exogenous progesterone, ovariectomy with exogenous estrogen, ovariectomy with exogenous estrogen and progesterone, and ovariectomy with either exogenous progesterone or estrogen and progesterone, plus uterine trauma. In pregnant females, uteroglobin levels diminished sharply after day 9. In pseudopregnancy, high concentrations were maintained through day 14. Although exogenous progesterone did not prevent this decrease in pseudopregnant females, re-elevation occurred in the continued presence of progesterone. A similar pattern of decline and re-elevation was found in ovariectomized females that received injections of estrogen and progesterone. With an increase in estrogen dosage, the period of uteroglobin secretion was shorter and the magnitude lower. Ovariectomized females receiving only progesterone did not manifest a clear uteroglobin diminution. Uterine trauma on day 7 of exogenous steroid administration to ovariectomized females was followed by a diminution in uteroglobin. At the dosage level used, administration of 20alpha-hydroxyprogesterone did not affect the peak uteroglobin secretion occurring on day 5 of pseudopregnancy. Ovariectomized females receiving estrogen or sesame oil vehicle had barely detectable levels of uteroglobin. A uteroglobin-estrogen complex is suggested as a possible inhibitor of uteroglobin synthesis by a feedback inhibition pathway in pseudopregnant females and in ovariectomized females treated with progesterone plus estrogen. In pregnant females, a uteroglobin-estrogen complex and/or the uterine decidual response to implantation could control uteroglobin synthesis.

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Acrosomal proteinase was found to be present in a highly organized distribution in the acrosomes of rabbit spermatozoa, using cytochemistry. This distribution consists of at least six linear loops of evenly spaced proteinase granules, which run diagonally across the flat side of the sperm head in a criss-crossing pattern. Two additional loops may be present, one encircling the tip of the spermatozoon in the region of the acrosome reaction, and the other at the posterior end of the acrosome. The results also seem to indicate that the enzyme granules are associated with the outer, and not the inner, acrosomal membrane.

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Acrosomal proteinase was found to be present in a highly organized distribution within the acrosomes of rabbit spermatozoa by cytochemistry. This distribution consists of at least six linear loops of evenly spaced proteinase granules, which run diagonally across the flat side of the sperm head in a crisscrossing pattern with the two most anterior loops surrounding the region of the acrosome reaction. This is the first description of an organized distribution of enzymes within a lysosome-like organelle.

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Treatment of both intact and hypophysectomized pregnant rats on days 19 and 20 of pregnancy with PGF2alpha results in a rapid fall in plasma progesterone concentrations by day 20 followed by premature delivery on day 21. Administration of depoprovera did not prevent the PGF2alpha-induced fall in progesterone levels but premature littering was adverted. Indomethacin, an inhibitor of prostaglandin biosynthesis, postponed the onset of parturition by 20 h when administered in late pregnancy but rats treated with both indomethacin and PGF2alpha delivered at the normal time. Treatment of both intact and hypophysectomized animals with indomethacin delayed the fall in plasma progesterone concentrations which normally occurs between days 21 and 22 of pregnancy. Concomitant PGF2alpha treatment of rats receiving indomethacin caused plasma progesterone levels to fall in a pattern similar to controls. These findings indicate that endogenous PGF2alpha induces a fall in blood progesterone concentrations which is followed by increased myometrial activity.

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Rabbit acrosomal proteinase from epididymal spermatozoa of 44 male rabbits was purified by subcellular fractionation, sucrose density gradient centrifugation, and electrofocusing; the specific activity of the purified product was 20,047 units per milligram, a value similar to that observed for pancreatic trypsins from various sources. The molecular weight determined from the amino acid analyses and ultracentrifugation was about 22,000. This rabbit acrosomal proteinase showed great similarity to pancreatic trypsin, especially to human pancreatic trypsin, both in the number of individual amino acids and in the total number of residues. This similarity was confirmed by an antigenic cross reaction between rabbit antiserum to bovine pancreatic trypsin with human, rabbit, rhesus monkey, and bull acrosotnal proteinase.

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