Generation of human-to-pig chimerism to induce tolerance through transcutaneous in utero injection of cord blood-derived mononuclear cells or human bone marrow mesenchymals cells in a preclinical program of liver xenotransplantation: preliminary results

OBJECTIVE

Using a percutaneous ecoguided injection system to obtain chimeric piglets through a less invasive and traumatic technique than previously reported.

MATERIALS AND METHODS

The two types of human cells included umbilical cord blood mononuclear elements and mesenchymal stem cells cultured from bone marrow. Four sows at gestational day 50 were anesthetized. A needle was inserted through the skin and uterine wall to reach the peritoneal cavity of the fetuses under continuous ultrasound guidance. Fourteen piglets were injected with various cell concentrations.

RESULTS

All sows carried pregnancies to term yielding 69 piglets, among which 67 were alive and two mummified. Two piglets died during the first 48 hours of life. Chimerism was detected using flow cytometry and by quantitative polymerase chain reaction (q-PCR) to detect Alu gene in blood or tissues samples. The analysis detected blood chimerism in 13 piglets (21%) by flow cytometry and the presence of the human Alu gene in 33 (51%) by q-PCR. The results suggest cell trafficking between littermates after in utero injection.

CONCLUSIONS

Transcutaneous echo-guided injection succeeded to produce chimeric piglets without disadvantages to the sow or the fetuses and avoiding abortions or fetal death.

EPR, ENDOR, and special TRIPLE measurements of P(*+) in wild type and modified reaction centers from Rb. sphaeroides

The influence of the protein environment on the primary electron donor, P, a bacteriochlorophyll a dimer, of reaction centers from Rhodobacter sphaeroides, has been investigated using electron paramagnetic resonance and electron nuclear double resonance spectroscopy. These techniques were used to probe the effects on P that are due to alteration of three amino acid residues, His L168, Asn L170, and Asn M199. The introduction of Glu at L168, Asp at L170, or Asp at M199 changes the oxidation/reduction midpoint potential of P in a pH-dependent manner (Williams et al. (2001) Biochemistry 40, 15403-15407). For the double mutant His L168 to Glu and Asn at L170 to Asp, excitation results in electron transfer along the A-side branch of cofactors at pH 7.2, but at pH 9.5, a long-lived state involving B-side cofactors is produced (Haffa et al. (2004) J Phys Chem B 108, 4-7). Using electron paramagnetic resonance spectroscopy, the mutants with alterations of each of the three individual residues and a double mutant, with changes at L168 and L170, were found to have increased linewidths of 10.1-11.0 G compared to the linewidth of 9.6 G for wild type. The Special TRIPLE spectra were pH dependent, and at pH 8, the introduction of aspartate at L170 increased the spin density ratio, rho (L)/rho (M), to 6.1 while an aspartate at the symmetry related position, M199, decreased the ratio to 0.7 compared to the value of 2.1 for wild type. These results indicate that the energy of the two halves of P changes by about 100 meV due to the mutations and are consistent with the interpretation that electrostatic interactions involving these amino acid residues contribute to the switch in pathway of electron transfer.

Evaluation of the triangular fibrocartilage in cadaveric wrists by means of arthrography, magnetic resonance (MR) imaging, and MR arthrography

PURPOSE

To evaluate the diagnostic accuracy of arthrography, magnetic resonance (MR) imaging, and MR arthrography in the detection and localization of defects of the triangular fibrocartilage (TFC) in cadaveric wrists, using arthroscopy as a reference standard.

MATERIAL AND METHODS

Twenty-four specimen wrists were evaluated. The different imaging modalities were blinded to reviewers and were interpreted independently. A classification of TFC defects was used for the evaluation of images in the different imaging modalities, thus permitting a more uniform correlation. Two cases were excluded from the MR imaging study because of poor image quality. Contingency tables with the chi-square test and Fisher's exact test were used for statistical analysis.

RESULTS

Defects of the TFC were identified in 17 of the 24 specimen wrists by means of arthroscopy, and 16 defects were observed when arthrography was carried out. With MR imaging 14 defects of the TFC were detected in the 22 specimen wrists evaluated, and with MR arthrography 16 defects were observed. Most defects were central or combined (two or more defects). In comparison to arthroscopy, the accepted diagnostic gold standard, the following results were found for arthrography in the detection of TFC defects: sensitivity 95%, specificity 100%, and accuracy 95% (P<0.0005); for MR imaging: sensitivity 86%, specificity 85%, and accuracy 70% (P<0.002); and for MR arthrography: sensitivity 100%, specificity 85%, and accuracy 95% (P<0.0005).

CONCLUSION

The results of the study seem to indicate that both arthrography and MR arthrography have high accuracy, and either would be useful for evaluation of the TFC. The combined approach using both techniques would have a very high accuracy equivalent to that resulting from arthroscopy.

A simple technique for shoulder arthrography

PURPOSE

To present a systematic approach to teaching a technique for arthrography of the shoulder. Using an adhesive marker-plate with radiopaque coordinates, precise sites for puncture can be identified and the need for fluoroscopic guidance obviated.

MATERIAL AND METHODS

Forty-six glenohumeral arthrograms were performed in 45 patients; in 1 case involving examination of both shoulders. The stages of the technique are described in detail, as are the fundamental aspects of achieving an effective glenohumeral injection. Pain intensity was measured in all patients using a verbal description scale.

RESULTS

Shoulder arthrography was successful in all cases. Average time taken for the procedure was 7 min, with no difference in the respective times required by an experienced radiologist and a resident. The procedure was well tolerated by most patients, with slight discomfort being observed in a very few cases.

CONCLUSION

The arthrographic technique used in this study is simple, safe, rapid, and reproducible, and has the advantage of precise localization of the site for puncture without need for fluoroscopic guidance. The procedure described in this study can be of help in teaching residents and can reduce the learning curve for radiologists with no experience in arthrographic methods. It also reduces the time of exposure to fluoroscopy.

Kinetics and mechanism of electron transfer in intact photosystem II and in the isolated reaction center: pheophytin is the primary electron acceptor

The mechanism and kinetics of electron transfer in isolated D1/D2-cyt(b559) photosystem (PS) II reaction centers (RCs) and in intact PSII cores have been studied by femtosecond transient absorption and kinetic compartment modeling. For intact PSII, a component of approximately 1.5 ps reflects the dominant energy-trapping kinetics from the antenna by the RC. A 5.5-ps component reflects the apparent lifetime of primary charge separation, which is faster by a factor of 8-12 than assumed so far. The 35-ps component represents the apparent lifetime of formation of a secondary radical pair, and the approximately 200-ps component represents the electron transfer to the Q(A) acceptor. In isolated RCs, the apparent lifetimes of primary and secondary charge separation are approximately 3 and 11 ps, respectively. It is shown (i) that pheophytin is reduced in the first step, and (ii) that the rate constants of electron transfer in the RC are identical for PSII cores and for isolated RCs. We interpret the first electron transfer step as electron donation from the primary electron donor Chl(acc D1). Thus, this mechanism, suggested earlier for isolated RCs at cryogenic temperatures, is also operative in intact PSII cores and in isolated RCs at ambient temperature. The effective rate constant of primary electron transfer from the equilibrated RC* excited state is 170-180 ns(-1), and the rate constant of secondary electron transfer is 120-130 ns(-1).

Visceral leishmaniasis: diagnosis by ultrasound-guided fine needle aspiration of an axillary node

A 77-year-old woman presented with fever up to 39 degrees C and acute pain in the left upper quadrant and renal fossa. Full blood count and biochemical screen revealed a haemoglobin (Hb) of 9.8 g dl(-1), an increased erythrocyte sedimentation rate and an elevated lactate dehydrogenase, all other parameters were normal. Thoracic and abdominal CT demonstrated two enlarged lymph nodes in the left axilla, and splenic infarcts. Ultrasound-guided fine needle aspiration of one of the axillary lymph nodes revealed macrophages filled with leishmanias.

[Corynebacterium urealyticum in renal trasplantation. CT and sonography imaging characteristics of encrusted cistitis and pielitis]

PURPOSE

Its described three cases of Corynebacterium urealyticum (CU) infection in patients with renal transplantation and one of its most serious consequences: encrusted pyelitis and cystitis. It is explained the principal keys for its diagnosis, based in the appearance of alkaline pH in in urine analysis (alkaline urine), positives urinary cultures for CU, and the CT and US studies revealed the characteristic images of calcifications in the wall of renal pelvis and bladder.

PATIENTS

Three male patients with renal transplantation and CU infection that caused encrusted pyelitis in two of the cases and encrusted cystitis in one case.

RESULTS

Calcifications of the urinary tract were noticed in CT in all the patients. In two cases bladder stones were linear, and in the third case they were fundamentally coarse and placed in pelvis. The diagnosis suspicion showed by the images was confirmed by the use of prolonged urine cultures, necessary for detecting CU. All the patients were treated with vancomycin, with success in two of the cases and, finally needing surgery, and after loss of the graft, in the other case.

CONCLUSION

Encrusted pyelitis and cystitis are cronic and severe infections of the urinary tract. Calcic struvite incrustations in the urothelium are characteristics of this infection. CT is a choice technique for the diagnosis and followup of the calcifications after treatment.

Palpable breast lesions: utility of Doppler sonography for diagnosis of malignancy

This study was designed to find whether there are any differences between benign and malignant palpable breast lesions as they are seen on grey-scale and colour-Doppler and on power-Doppler sonography; to determine which variables for each technique are most helpful in distinguishing any such differences; and to see whether the use of an echo-enhancing agent gives better results in the differential diagnosis. Forty-five palpable breast lesions (16 benign and 29 malignant) were evaluated in a preoperative study using grey-scale sonography, colour-Doppler sonography and power-Doppler sonography before and after administration of an echo-enhancing agent (Levovist). We reached the following conclusions: (1) In the grey-scale ultrasound study of palpable breast lesions the presence of microcalcifications, acoustic shadowing and non-well-defined margins are related to malignancy. (2) Colour- and power-Doppler sonography may help in the differential diagnosis. (3) The use of an echo enhancer (Levovist) accentuates these differences and enables them to be noted in other variables, such as pulsatility index, nodule-to-vascularity ratio and number of poles.

Case report: Conservative management of an arteriovenous fistula of the inferior epigastric artery

We present a case of pseudoaneurysm and arteriovenous fistula of the inferior epigastric artery secondary to the placement of a drain during a surgical intervention. We stress the utility of colour Doppler ultrasound and arteriography embolisation in diagnosis and treatment, respectively.

Long-lived charge-separated states in bacterial reaction centers isolated from Rhodobacter sphaeroides

We studied the accumulation of long-lived charge-separated states in reaction centers isolated from Rhodobacter sphaeroides, using continuous illumination, or trains of single-turnover flashes. We found that under both conditions a long-lived state was produced with a quantum yield of about 1%. This long-lived species resembles the normal P(+)Q(-) state in all respects, but has a lifetime of several minutes. Under continuous illumination the long-lived state can be accumulated, leading to close to full conversion of the reaction centers into this state. The lifetime of this accumulated state varies from a few minutes up to more than 20 min, and depends on the illumination history. Surprisingly, the lifetime and quantum yield do not depend on the presence of the secondary quinone, Q(B). Under oxygen-free conditions the accumulation was reversible, no changes in the normal recombination times were observed due to the intense illumination. The long-lived state is responsible for most of the dark adaptation and hysteresis effects observed in room temperature experiments. A simple method for quinone extraction and reconstitution was developed.

High-resolution ultrasound associated with aspiration biopsy in the follow-up of patients with differentiated thyroid cancer

OBJECTIVE: To assess the value of ultrasound in the follow-up of patients undergoing surgery for differentiated thyroid carcinoma.

SUBJECTS: The study included 89 patients (70 women and 19 men) with differentiated thyroid carcinoma (76 papillary and 13 follicular cancer).

METHODS: High-frequency ultrasound (US) was used in the evaluation of 89 subjects who underwent surgery for thyroid carcinoma. Fine-needle aspiration was performed in cases with positive US. In addition, determinations of thyroglobulin (Tgb) in serum, scintigraphy with 131I, and cervical palpation were evaluated. We determined sensitivity, specificity, and overall accuracy for each of these diagnostic methods.

RESULTS: Ultrasonography was positive in 22 subjects, 16 in the nodal area and 6 in the thyroid bed. Twenty-two subjects received fine-needle aspiration with US control; 13 (59%) of 22 were positive for cancer. The results of the US for detecting neoplastic disease showed a sensitivity of 65%, specificity of 86%, and overall accuracy of 82%. The overall accuracy for scintigraphy was 88% and for Tgb, 91%.

CONCLUSION: We concluded that US can be included in the follow-up protocol for patients undergoing surgery for differentiated cancer of thyroid, as a valuable tool to localize the recurrence. This technique is particularly useful in the evaluation of patients who are found to have elevated Tgb levels.

The treatment of differentiated thyroid cancer includes surgery and, in some cases, the ablation of residual thyroid tissue with therapeutic doses of iodine 131I. 1 The posttreatment search for recurrence or metastases is based on periodic body scanning with 131I and determination of serum thyroglobulin (Tgb) levels. 2,3

High-resolution ultrasound (US; 10 MHz) has been found to have a high sensitivity in diagnosing nonpalpable cervical masses. 4–6 Thus the possibility exists that including it in the protocols for follow-up of differentiated thyroid cancer may be valuable.

The aim of our study was to assess the value of high-resolution US (associated with directed fine-needle aspiration [FNA] biopsy) in the follow-up of patients undergoing surgery for papillary and follicular thyroid cancer.

[Burkitt's lymphoma: atypical localization]

We present a case of Burkitt's lymphoma, American type, with massive abdominal involvement, in a 11 years old boy, who presented with mucous-cutaneous paleness, cephalalgia and melaena. The localization of the lesion in the gallbladder and the rectum is stressed as being exceptional. We emphasize the importance of a rapid diagnosis to start early chemotherapy because this lesion grows rapidly. In our case after eight days of chemotherapy treatment there was a 75% reduction of the tumor mass.