Renal ablative cryosurgery in selected patients with peripheral renal masses

OBJECTIVES

To present the preliminary results of renal ablative cryosurgery in selected patients.

METHODS

Seven patients were treated, all of whom had small peripheral tumors and chose not to undergo partial or radical nephrectomy. Four patients underwent a rib-sparing flank incision; the remaining three underwent laparoscopy. All tumors were biopsied before cryoablation. Intraoperative ultrasound was used to monitor the cryolesion.

RESULTS

There were no intraoperative complications. The estimated blood loss averaged 111 mL. To date, 6 of the 7 patients have undergone at least one follow-up computed tomography scan (14.2 months average follow-up); all these scans demonstrated partial resolution of the lesion. Clinically, the patients tolerated the procedure without any renal complications or significant changes in creatinine.

CONCLUSIONS

This limited clinical trial has demonstrated the feasibility of treating small peripherally located renal tumors with cryosurgery with minimal morbidity and a favorable outcome. Further studies are necessary to determine the long-term efficacy of this treatment modality.

Fungi from geothermal soils in Yellowstone National Park

Geothermal soils near Amphitheater Springs in Yellowstone National Park were characterized by high temperatures (up to 70 degrees C), high heavy metal content, low pH values (down to pH 2.7), sparse vegetation, and limited organic carbon. From these soils we cultured 16 fungal species. Two of these species were thermophilic, and six were thermotolerant. We cultured only three of these species from nearby cool (0 to 22 degrees C) soils. Transect studies revealed that higher numbers of CFUs occurred in and below the root zone of the perennial plant Dichanthelium lanuginosum (hot springs panic grass). The dynamics of fungal CFUs in geothermal soil and nearby nongeothermal soil were investigated for 12 months by examining soil cores and in situ mesocosms. For all of the fungal species studied, the temperature of the soil from which the organisms were cultured corresponded with their optimum axenic growth temperature.

Evidence for early hematopoietic progenitor cell involvement in acute promyelocytic leukemia

Acute promyelocytic leukemia (APL) represents a subtype of acute myeloid leukemia with characteristic morphologic, molecular, and immunophenotypic features. Previous immunophenotypic analyses have shown that leukemic cells in APL typically express the myeloid markers CD33 and CD13 but lack expression of the early hematopoietic progenitor cell antigens CD34 and HLA-DR. We analyzed selected immunophenotypic features of APL by flow cytometry and showed that 7 (41%) of 17 cases contained significant subsets of CD34+ leukemic cells: CD34+ myeloid cells predominated in 2 APL cases. By using a fluorescence-activated cell sorter-fluorescence in situ hybridization approach, we confirmed that the CD34+ cells harbored the t(15;17) translocation characteristic of APL. By using the same experimental approach, CD34+ populations were stratified into primitive CD34+ CD38- and committed CD34+ CD38+ progenitor cell subpopulations; cells in both subsets contained the t(15;17) translocation. The knowledge that APL may be partly or largely CD34+ is important for proper diagnosis. Furthermore, identification of the t(15;17) translocation in CD34+ CD38- blasts indicates that, in at least some cases, the leukemogenic mutation in APL occurs within primitive hematopoietic progenitor cells.

Complex associations between HLA-DRB1 genes and female rheumatoid arthritis: results from a prospective study

We followed 138 Spanish patients (37 men and 101 women) with rheumatoid arthritis (RA) to analyze whether patient sex influenced the HLA-DRB1 associations with disease susceptibility. Results showed that, although a high increase of the shared epitope (SE) was observed in both genders, distribution of HLA-DRB1 specificities differs from males to females: DR1 was increased among male patients, whereas DR4 as well as DR10 were preferentially associated with female RA. To further explore whether this phenomenon operates either on susceptibility or on disease progression, 82 patients (25 males and 57 females) among the whole group were followed during the first 8 to 10 years of their disease. Results from this prospective study showed that the association of the SE with radiological disease severity was found in both male and female patients, although it was stronger among the latter group. Interestingly, DR1- as well as DR4-related alleles contributed to the high frequency of SE among female patients with early small-joints severe RA and/or long-term large-joint erosions. These results suggest that HLA polymorphism might be involved in RA pathogenesis through two mechanisms: (a) in combination with patient sex, operating in disease induction; and (b) independent of patient sex, influencing disease severity and progression.

Effects of feedback projections from area 18 layers 2/3 to area 17 layers 2/3 in the cat visual cortex

In the absence of a direct geniculate input, area 17 cells in the cat are nevertheless able to respond to visual stimuli because of feedback connections from area 18. Anatomic studies have shown that, in the cat visual cortex, layer 5 of area 18 projects to layer 5 of area 17, and layers 2/3 of area 18 project to layers 2/3 of area 17. What is the specific role of these connections? Previous studies have examined the effect of area 18 layer 5 blockade on cells in area 17 layer 5. Here we examine whether the feedback connections from layers 2/3 of area 18 influence the orientation tuning and velocity tuning of cells in layers 2/3 of area 17. Experiments were carried out in anesthetized and paralyzed cats. We blocked reversibly a small region (300 microm radius) in layers 2/3 of area 18 by iontophoretic application of GABA and recorded simultaneously from cells in layers 2/3 of area 17 while stimulating with oriented sweeping bars. Area 17 cells showed either enhanced or suppressed visual responses to sweeping bars of various orientations and velocities during area 18 blockade. For most area 17 cells, orientation bandwidths remained unaltered, and we never observed visual responses during blockade that were absent completely in the preblockade condition. This suggests that area 18 layers 2/3 modulate visual responses in area 17 layers 2/3 without fundamentally altering their specificity.

Full window stereo

Visualisation is the bioinformaticist's most important tool for the study of macromolecules, and being able to see molecules in stereo is a crucial aspect. Stereo vision is based on the principle that each eye is presented with the best possible image of what it would have seen if the object was really there in 3D. The simplest approach to stereo vision is to display the right eye picture on the right half of the screen and the left eye picture on the left half while using a mirror system to ensure that each eye sees what it is supposed to see. More expensive workstations use hardware to alternately display the left and right eye pictures while synchronously blocking the transparency in the right or left lens of the special glasses worn by the user. We present here some simple software that uses inexpensive hardware, originally designed for the computer game industry, to make full screen stereo available on Linux-based PCs. The quality of the stereo vision is similar to the top-of-the-line graphics workstations that are capable of quad-buffering. This stereo option has been incorporated in the XII based version of WHAT IF (Vriend, G. J. Mol. Graphics 1990, 8, 52-56), but the stereo source code is freely available and can easily be incorporated in other visualization packages.

Detection of adenocarcinoma by urinary microsatellite analysis after augmentation cystoplasty

Augmentation cystoplasty is associated with an increased risk of bladder cancer development between 10 and 20 years after augmentation. Using microsatellite analysis, we analyzed urine obtained before surgical resection of the malignant lesion from a patient who developed invasive adenocarcinoma after augmentation cystoplasty. Loss of heterozygosity was identified in both urine and tumor samples from this patient. This observation suggests that microsatellite urine analysis may be useful as a monitoring tool for patients after augmentation cystoplasty.

Preclinical evaluation of a synthetic Plasmodium falciparum MAP malaria vaccine in Aotus monkeys and mice

Multiple antigen peptides (MAPs) containing epitopes of the major surface protein of the malaria sporozoite, the circumsporozoite (CS) protein, have been shown in previous studies to elicit antibody-mediated protection against sporozoite challenge in experimental murine and simian hosts. For the preparation for a phase I trial of a P. falciparum (T1B)4 MAP, which contains T and B cell epitopes from the CS repeat region, pre-clinical immunogenicity and adjuvant formulation studies were carried out in mice and Aotus monkeys. The (T1B)4 MAP was found to be immunogenic in three different species of owl monkeys, Aotus nancymae, A. vociferans and A. nigriceps. Optimal antibody responses were obtained in A. nancymae immunized s.c. with (T1B)4 MAP emulsified in Freund's, in which peak titers of over 10(6) were obtained in individual monkeys. MAP immunized A. vociferans also developed high levels of anti-sporozoite antibodies, although the kinetics and the magnitude of the response differed from A. nancymae. (T1B)4 MAP adsorbed to alum (aluminum hydroxide), a formulation that is acceptable for human use, was less immunogenic in naive A. nancymae, as well as A. nigriceps. The injection of MAPs/alum, however, significantly enhanced antibody responses in sporozoite-primed monkeys, suggesting that the administration of the MAP vaccine may be an effective means to increase the low levels of antibody present in individuals living in malaria endemic areas. The addition of a co-adjuvant QS-21, a purified saponin, significantly increased the immunogenicity of the alum-adsorbed MAP in both mice and monkeys, providing a vaccine formulation suitable for phase I trials in human volunteers.

Antiviral therapy for HIV patients with renal insufficiency

Patients with HIV infection and HIV-related opportunistic infections are treated extensively with a spectrum of drugs. Introduction of new antiretroviral drugs, such as protease inhibitors and nonnucleoside reverse transcriptase inhibitors in addition to nucleoside reverse transcriptase inhibitors, has created exciting dimensions in treatment strategies. Renal dysfunction is also common in HIV-infected patients. Because some drugs used in HIV are primarily excreted unchanged by the kidney, dose adjustments are necessary in patients with renal insufficiency. Drugs such as foscarnet, cidofovir and adefovir are directly nephrotoxic, whereas acyclovir can crystallize in the kidneys, and indinavir may cause nephrolithiasis. This paper reviews the impact of renal insufficiency on pharmacokinetics of antiviral drugs used in HIV disease and discusses dosage recommendations needed to avoid toxicity. Finally, we summarize the effects of dialysis on removal of these drugs.

Sequence and diversity of T-cell receptor beta-chain V and J genes of the owl monkey Aotus nancymaae

The New World primate Aotus nancymaae is susceptible to infection with the human malaria parasite Plasmodium falciparum and has therefore been recommended by the World Health Organization as a model for the evaluation of malaria vaccine candidates. Recently, we have shown that Aotus TCRVA genes and TCRJA segments exhibit a high degree of similarity to human counterparts. In the present report we used reverse transcription polymerase chain reaction to analyze the sequences of A. nancymaae TCR beta-chain gene rearrangements. Alignment with human sequences and phylogenetic comparison identified 18 distinct Aotus TCRBV genes homologous to the human TCRBV gene families 2, 4, 5, 6, 7, 9, 12, 15, 24, and 28. Multiple Aotus genes were found in the TCRBV4, 5, 6, and 7 families. Some of these TCRBV genes aligned best to the same human gene and thus do not seem to have separate human homologues. Amino acid sequences of the Aotus TCRBV genes were 77 to 90% identical to their closest human counterparts. Ten distinct Aotus TCRBJ segments homologous to the human segments J1-1, J1-2, J1-4, J1-5, J1-6, J2-1, J2-2, J2-3, J2-4, J2-5 were found. In some cases the amino acid sequences of Aotus and human TCRBJ segments were completely identical. A comparison of the proportion of synonymous and non-synonymous substitutions in Aotus vs human beta-chain-encoding genes revealed a dominance of synonymous substitutions in TCRBJ segments and of nonsynonymous substitutions in TCRBV segments. Dominance of nonsynonymous substitutions was more pronounced in TCRBV CDR1 and CDR2 regions than in the framework regions. No evidence for the emergence of new TCRBJ segments or TCRBV families was found. These results confirm that the TCR repertoire in primates is remarkably stable and support the concept of using Aotus monkeys as an infection model for the evaluation of future subunit vaccine candidates.

The spatial properties of a model neuron increase its coding range

The coding properties of one-compartment and two-compartment model neurons are compared. The membrane depolarization in both models is described as a deterministic leaky integrator. Interspike intervals are identified with the periods between reset of the depolarization after firing and consecutive crossing of a fixed firing threshold. The two-point model has an input in the dendritic compartment and an output in the trigger-zone compartment. it is shown that the sensitivity threshold for the two-point model is shifted to the larger values of the input intensity with respect to the sensitivity threshold of its single-point counterpart. Further, its coding range is substantially larger than the coding range of the single-point model.

The power of the collective: battered migrant farmworker women creating safe spaces

In this article I describe the use of a participatory action research (PAR) methodology to address the problem of domestic violence among migrant farmworker (MFW) women in California. The article was generated from a variety of data sources used by the investigator over a 4-year period. These include the investigator's observations, field notes, informal conversations, written stories from the women, and interviews. The "power of the collective" is discussed as the development of a power base for battered MFW women to support and take care of one another. The concepts of liberation, enlightenment, and "conscientizacion" are used to describe the evolution of the collective.

Relationship between ANCA and disease activity in small vessel vasculitis patients with anti-MPO ANCA

BACKGROUND

We analysed the usefulness of antineutrophil cytoplasmic antibodies (ANCA) as a marker of clinical activity in patients with small vessel vasculitis associated with anti-myeloperoxidase (MPO) ANCA.

METHODS

We studied a group of 25 patients, 15 with microscopic polyangitis and 10 with renal limited vasculitis, so-called rapidly progressive glomerulonephritis type III. The clinical and serological follow-up was accomplished quarterly over an average of 2.79 +/- 2.08 years (range 0.25-6 years). ANCA was analysed by indirect immunofluorescence and enzyme-linked immunosorbent assays (ELISAs).

RESULTS

At the time of diagnosis, all patients were ANCA positive (P-ANCA and anti-MPO). Following a standardized treatment, all patients except one achieved complete remission of vasculitis in <3 months. One patient suddenly died during the active phase (1 month of follow-up) and with positive ANCA. Seroconversion from positive to negative occurred in 24/25 patients (96%). Eighteen of these 24 patients (75%) achieved the seroconversion within the first 6 months. During the follow-up, two patients had four major relapses, all of them associated with positive ANCA. ANCA seroconversion from negative to positive was observed in one patient with microscopic polyangitis without clinical relapse of vasculitis.

CONCLUSION

ANCA should be used in conjunction with other markers of disease activity in the management of microscopic polyangitis and renal limited vasculitis patients with anti-MPO ANCA.

In vitro fertilization is associated with an increased risk of hypospadias

PURPOSE

The purpose of this study was to determine if there is an increased incidence of hypospadias in male offspring conceived by in vitro fertilization (IVF).

MATERIALS AND METHODS

A retrospective institutional chart review from 1988 to 1992 and data from the Maryland Birth Defects Registry were statistically analyzed to assess the risk of hypospadias with IVF.

RESULTS

The data for the 5-year period indicated a 5-fold increased risk of hypospadias after IVF, with an incidence of approximately 1.5% in the IVF group and 0.3% in the control group. The only recognized difference between the groups was maternal progesterone administration in the IVF group but the cause of the increased risk of hypospadias was unknown. The distribution of hypospadias severity was similar in both groups.

CONCLUSIONS

Male newborns conceived by IVF have a 5-fold increased risk of hypospadias, which may be related to maternal progesterone administration, or other maternal or fetal endocrine abnormalities that may or may not be related to infertility. Health care providers should be aware of this risk so that they can properly counsel infertile couples seeking assisted reproduction by IVF technology.

DNA content by flow cytometry in gastric carcinoma: pathology, ploidy and prognosis

BACKGROUND/AIMS

The prognostic relevance of histopathologic findings in gastric carcinoma is well established. Studies on DNA-ploidy are still scanty and contradictory.

METHODOLOGY

Histopathologic parameters, DNA ploidy and S-phase were evaluated in 78 cancer patients curatively resected, using formalin-fixed paraffin-embedded tissue.

RESULTS

Thirty-nine tumors (50%) were aneuploid. No significant correlation was found between histologic data and ploidy, but tumors with nodal involvement were more frequently aneuploid. In univariate analysis, tumor location (p=0.05), tumor size (p=0.01), differentiation grade (p=0.02), Lauren classification (p=0.01), deeper infiltration of gastric wall (p=0.001), nodal affectation (p=0.0000) and number of lymph nodes (p=0.01), TNM stage (p=0.0000), type of gastrectomy performed (p=0.04), and DNA ploidy (p=0.04) significantly influenced survival. S-phase values had no effect on prognosis. In the multiple regression model, factors independently associated with survival were TNM stage (p=0.0009), nodal affectation (p=0.01) and, marginally, ploidy (p=0.08).

CONCLUSIONS

In gastric carcinoma curatively resected, the more relevant prognostic factors were stage and nodal involvement. Fifty percent of the tumors were aneuploid. Aneuploidy was significantly associated with poorer prognosis.

Laparoscopic renal cryoablation: acute and long-term clinical, radiographic, and pathologic effects in an animal model and application in a clinical trial

OBJECTIVES

To evaluate renal cryosurgery by studying the feasibility of laparoscopic delivery and the radiographic characteristics and histopathologic effects in a porcine model using different freeze cycles. On the basis of the results, a clinical trial of laparoscopic cryosurgical ablation in select patients with clinical stage T1 renal tumors was started.

MATERIALS AND METHODS

Twelve kidneys from six farm pigs underwent cryosurgery. Each kidney was treated with two freeze cycles to -180 degrees C. Six kidneys were retroperitonealized, and six were not. An abdominal CT scan was performed at various times to evaluate for the presence of urinoma or hematoma and to monitor lesion changes. Organs were harvested at times ranging from 24 hours to 13 weeks. Radiographic and histopathologic changes were recorded for each time period. Eight patients with small (average 2-cm) exophytic renal masses underwent laparoscopic biopsy and cryosurgical ablation using a 3- or 4.8-mm probe (Cryomedical Sciences Inc., Rockville, MD) for one 15-minute or two 5-minute freeze cycles to a temperature of -180 degrees C to extend the ice ball at least 7 mm beyond the tumor margin.

RESULTS

Dense adhesions between the bowel and cryoablated renal tissue were encountered in all non-retroperitonealized kidneys, but no fistula formation was present. The retroperitonealized kidneys had minimal adhesion formation. None of the animals developed a urinary fistula. At 24 hours and 1 week, CT scanning demonstrated an enhancement defect corresponding to the region of the ice ball with no urinoma or hematoma. At 13 weeks, only a nonenhancing cortical defect was seen. At immediate harvest, hemorrhage was noted in the area of the ice ball with a sharp demarcation at the edge of the freeze zone. At 1 week, four distinct zones were seen: central necrosis, inflammatory infiltrate, hemorrhage, and fibrosis with regeneration. At 13 weeks, the necrotic tissue had been replaced with a circumscribed area of fibrosis. There were no intraoperative or postoperative complications in the eight patients. The estimated blood loss was 140 mL, and the mean hospital stay was 3.5 days. At a mean clinical follow-up of 7.7 (range 1-18) months and radiographic follow-up of 5 months; there have been no tumor recurrences or significant changes in the serum creatinine concentration. At 24 hours, there was an enhancement defect in the area of the ice ball. The CT images at 13 weeks showed a nonenhancing cortical defect in the area of the ice ball.

CONCLUSIONS

Cryosurgery can be readily delivered laparoscopically, creating a discrete lesion at the time of treatment that appears to be consistent over time. In the animal studies, complete tissue necrosis developed in the freeze zone, followed by reabsorption, and by 13 weeks, fibrous tissue had replaced the defect. In the animal and human trials, there were no operative complications, urinomas, hematomas, or bowel or urinary fistulas. Follow-up imaging in human trials revealed a persistent nonenhancing defect in the area of the freeze zone. Long-term clinical follow-up will be necessary to determine the cancer-free survival rate.