CCR2(+)CD103(-) intestinal dendritic cells develop from DC-committed precursors and induce interleukin-17 production by T cells

The identification of intestinal macrophages (mφs) and dendritic cells (DCs) is a matter of intense debate. Although CD103(+) mononuclear phagocytes (MPs) appear to be genuine DCs, the nature and origins of CD103(-) MPs remain controversial. We show here that intestinal CD103(-)CD11b(+) MPs can be separated clearly into DCs and mφs based on phenotype, gene profile, and kinetics. CD64(-)CD103(-)CD11b(+) MPs are classical DCs, being derived from Flt3 ligand-dependent, DC-committed precursors, not Ly6C(hi) monocytes. Surprisingly, a significant proportion of these CD103(-)CD11b(+) DCs express CCR2 and there is a selective decrease in CD103(-)CD11b(+) DCs in mice lacking this chemokine receptor. CCR2(+)CD103(-) DCs are present in both the murine and human intestine, drive interleukin (IL)-17a production by T cells in vitro, and show constitutive expression of IL-12/IL-23p40. These data highlight the heterogeneity of intestinal DCs and reveal a bona fide population of CCR2(+) DCs that is involved in priming mucosal T helper type 17 (Th17) responses.

FiberWire is superior in strength to stainless steel wire for tension band fixation of transverse patellar fractures

BACKGROUND

The metal implants used to achieve fixation of displaced transverse patellar fractures are associated with implant failure, postoperative pain and a significant re-operation rate. Recent studies have examined braided suture as a possible alternative to stainless steel wire to increase patient satisfaction and decrease re-operation rates, but suture has not demonstrated clearly superior fixation strength. FiberWire is a reinforced braided polyblend suture that has demonstrated superior characteristics to the previous sutures studied and has not to our knowledge been examined as a material for tension band fixation of transverse patellar fractures.

METHODS

Materials testing was performed on repeated samples of No. 5 FiberWire suture and 18-gauge stainless steel wire. The strength and stiffness of each material was measured. The two materials were then used for tension band fixation on a novel transverse patellar fracture model and tested to failure by three-point bending. The constructs included a single stainless steel wire, a single-strand FiberWire tied with a sliding knot, double-strand FiberWire tied with sliding knots and double-strand FiberWire tied with a Wagoner's Hitch. The fixation strength and stiffness of the constructs were measured.

FINDINGS

Unlike stainless steel, FiberWire maintained its initial stiffness until failure. Furthermore, during three-point-bend testing, double-strand FiberWire was found to have a significantly higher failure load than stainless steel wire when the suture was tied and locked under the tension produced by a modified Wagoner's Hitch.

INTERPRETATION

FiberWire is a potentially superior alternative to stainless steel wire in tension band fixation of transverse patellar fractures.

Hydrogen peroxide decomposition in the oral cavity

PURPOSE

To determine the clearance of hydrogen peroxide from the oral cavity of infants (3-4 yrs of age), juveniles (7-12 yrs of age), adults (35-66 yrs of age), and adults with impaired salivary flow (34-71 yrs of age).

MATERIALS AND METHODS

In all subjects, the amount of H2O2 present in the oral cavity was assessed following a 1-min brushing period with an experimental dentifrice formulated with 3% hydrogen peroxide for up to 9 mins postbrushing. In addition, the oral clearance of 3% hydrogen peroxide delivered in an experimental dentifrice formulated with 5% baking soda was determined in a control population of adults and adult subjects with impaired salivary flow.

RESULTS

Most of the hydrogen peroxide decomposed during brushing, with less than 30% of the prebrushing dose of hydrogen peroxide remaining in the oral cavity after 1 min of brushing. No differences between infants, juveniles, and adults were seen in levels of hydrogen peroxide recovered from the oral cavity after tooth brushing. When a mixture of hydrogen peroxide and baking soda was used for brushing, less than 5% of the hydrogen peroxide was recovered from the oral cavity after 1 min of brushing. In conclusion, clearance of hydrogen peroxide from the oral cavity was very rapid in children, adults, and adults with impaired salivary flow. Decomposition of hydrogen peroxide was enhanced approximately six-fold in adults by the presence of baking soda in the dentifrice. No substantial amount of hydrogen peroxide survived beyond the brushing period, and very little material would be present to interact with soft tissues in the oral cavity after expectorating any remaining dentifrice containing hydrogen peroxide.

Behavior and use of nonaqueous media without supporting electrolyte in capillary electrophoresis and capillary electrochromatography

Five nonaqueous solvents (acetonitrile, methanol, N,N-dimethylformamide, dimethyl sulfoxide, formamide) and deionized water were investigated for their ability to support electroosmotic flow (EOF) without electrolytic additives. In general, flow was found to be equal to or greater than flow with typical CE buffer systems. The magnitude of EOF was determined for each solvent by open tubular capillary electrophoresis (CE) and related to viscosity (eta), dielectric constant (epsilon), and the ratio of dielectric constant to viscosity (eta/epsilon). Zeta potentials (zeta) were derived indirectly from flow data and tabulated. Comparisons of flow behavior and zeta were made between pure solvents and conventional CE buffers, and questions of equilibrium and reproducibility were addressed. Similar experiments were performed using hydroorganic mobile phases (ACN/water, MeOH/water) across the complete compositional range (100% water-100% organic), with flow characteristics and zeta reported for each mobile phase system. Packed capillary columns (5-microns ODS) were evaluated for flow and retention stability under capillary electrochromatographic (CEC) conditions. A separation of 11 polycyclic aromatic hydrocarbons was performed in under 13 min by CEC with an ACN/water mobile phase. Reduced plate heights (h) were calculated between 2.5 and 3.0 for solutes with capacity factors (k') up to 4.5 for the most retained solute.

Silver(I)-mediated separations by capillary zone electrophoresis and micellar electrokinetic chromatography: argentation electrophoresis

The addition of Ag(I) to the run buffer in capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC), containing sodium dodecyl sulfate, applies the principles of argentation chromatography to electrophoretic separations and is termed "argentation electrophoresis". This technique is shown to provide a complementary method to CZE and MEKC for the separation of specific types of solutes that selectively complex with Ag(I). Baseline resolution in the CZE separation of nine sulfonamides is achieved by the addition of 50 mM silver nitrate to the run buffer. Retention mechanisms in MEKC separations can also be manipulated by the addition of Ag(I) to the micellar solution. Only slight resolution of a pair of sulfonamides was achieved under normal MEKC conditions. Upon the addition of Ag(I) to the mobile phase containing SDS micelles, baseline resolution of the compounds is shown. The retention order and resolution of five sulfonamides changed significantly when 25 mM Ag(I) was added to the SDS-containing buffer. The use of Ag(I) addition in MEKC is also applied to the separation of various other compounds that show selectivity toward Ag(I) complexation, including S-containing heterocycles and vitamin D compounds. The effect of the addition of Ag(I) on the elution range in MEKC is also investigated. A steady increase in the elution range is seen upon increasing the concentration of Ag(I). With a constant percentage of organic modifier (15%), the addition of higher concentrations of silver nitrate (25-50 mM) results in elution ranges greater than 12. The results using Ag(I) as buffer additives in MEKC are also compared to studies utilizing a mixed counterion surfactant of sodium/silver dodecyl sulfate.

Potentiation of the toxicity of model hepatotoxicants by acetaminophen

A 24-hr oral pretreatment of rats with 1.6 g/kg acetaminophen potentiated hepatotoxicity of allyl alcohol, bromobenzene, carbon tetrachloride, 1,1-dichloroethylene, and thioacetamide, as assessed by elevation of serum alanine aminotransferase activity and histopathological examination. Doses, of these hepatotoxicants, which did not cause hepatocellular necrosis, became necrogenic after acetaminophen pretreatment with all toxicants except thioacetamide. Acetaminophen pretreatment did not decrease the threshold dose of toxicity for thioacetamide but did accentuate hepatotoxic doses. Acetaminophen pretreatment potentiated lethality of allyl alcohol and 1,1-dichloroethylene. Upon necropsy, these rats had congested livers and appeared to suffer from hypovolemic shock. We conclude that while acetaminophen was not necrogenic at the doses used in this study, it produced alterations that make hepatocytes much more susceptible to hepatotoxic insult.

Primary adenocarcinoma localized to the fallopian tubes: report on 33 cases

Thirty-three cases of primary adenocarcinoma localized to the fallopian tubes were analyzed according to prognostic factors such as depth of infiltration, tumor differentiation, and lymph vessel invasion. Fifteen patients (45, 5%) died of recurrence within 5 years. Only for positive vessel invasion was the survival significance worse. Combination chemotherapy seems promising compared to radiotherapy in these early stages.

Estrogen and progesterone receptors in normal and malignant vulvar tissue

Cytoplasmic receptors for 17 beta-estradiol (ER) and progesterone (PR) were measured in vulvar carcinomas. Tissues from 12 patients were examined. 5 of the vulvar carcinomas had detectable amounts of ER of whom 1 also had positive PR. Tissue samples from normal vulvar skin in 9 of the same patients were also examined for ER and PR activity. 3 had positive ER only and 1 had both ER and PR activity. The concentration of ER in cancer tissue showed a binding capacity of 2-23 pmol/g cytosol protein. In receptor-positive normal vulvar skin the binding capacity of ER ranged between 4 and 10 pmol/g cytosol protein. The binding capacity or PR, positive in 1 vulvar carcinoma and in 1 normal skin sample, was 12 and 10 pmol/g cytosol protein, respectively.

The effect of dexamethasone therapy in prolonged pregnancy

Fifty-six patients, chosen by random sampling from a total group of 120 post-term women, received dexamethasone (Decadron, "MSD" 2 mg 3 times a day for 4 days, the other 64 patients acting as controls. The evolution of uterine activity was evaluated using pelvic score (PS) and a modified low dosage oxytocin sensitivyt test (OST) before (T1) and after (T2) the treatment. During the interval from the second to the 6th day inclusive after T1 35 women of the dexamethasone group and 15 of the control group had a spontaneous onset of labour (SO) (0.001 less than P less than 0.01). Five patients in the dexamethasone group with primary rupture of membranes started labour spontaneously within 12 hours after membrane rupture, 7 patients in the control group with primary rupture of membranes received oxytocin as labour did not start within 24 hours. Excluding patients artifically induced, the mean interval from T1 to SO was 6.8 days in the control group and 5.2 days in the dexamethasone group (P less than 0.001). In both groups PS and the sum of Montevideo units (MU) during OST increased from T1 to T2, the increase was significantly greater in the dexamethasone group than in the control group. We found no correlation between the results of OST and the T1--SO interval. Dexamethasone, as used in this study, may promote labour in prolonged human pregnancy. Due to its low potency, it is not a substitute for oxytocin in the induction of labour. The lowered placento-fetal quotient in the dexamethasone group warrants further study of the effects of steroid hormone on placental function.

Studies on the 1967-8 foot-and-mouth disease epidemic. The relation of weather to the spread of disease

An analysis of the 1967-8 foot-and-mouth disease epidemic with reference to the initial spread, the origin of outbreaks more than 60 km. from the main epidemic area, the series of outbreaks near Worcester, a specific case history and the daily rate of spread of the epidemic, strongly suggests that the weather played a major part in the spread of disease. The two main factors involved in this type of spread are wind and precipitation. It is noted that after the epidemic had been checked, following anticyclonic weather, the association between the weather and the spread of disease was less apparent.