Effects of N-acetylcysteine on myoglobinuric-acute renal failure in rats

Oxygen metabolites play an important role in renal injury during myoglobinuric acute renal failure (ARF). This study was designed to determine the protective influence of N-acetylcysteine (NAC), a hydroxyl radical scavenger, and treatment in an experimental model of myoglobinuric-ARF induced by intramuscular injection of hypertonic glycerol in rats. The rats were randomly distributed into five groups: Group 0 (n = 10), was assigned to receive 2mL saline (0,9%) intraperitoneally (ip); Group 1 (n = 10), NAC ip in a dose of 0 mg/100 g of body weight 30 min before the intramuscular (im) injection of 50% glycerol (10 mg/kg); Group 2 (n = 10), received saline 0,9% ip in a equivalent volume of NAC in Group I before the im injection of glycerol; Group 3 (n = 10), received NAC ip in a dose of 10 mg/100 g after im injection of glycerol; Group 4 (n = 10), saline 0,9% ip in a equivalent volume of NAC of the Group 3 after im administration of glycerol. After 24 h rats were sacrificed and kidney morphology and renal function were determined. A severe renal failure was produced by glycerol injection in the Groups 1, 2, 3, and 4, with significant tubular proximal necrosis and cast formation, and creatinine and urea concentrations were elevated in these groups without significant differences among groups, but Group 0 where the values were significantly lower. The results of this study suggests that ip administration of NAC in rats before or after glycerol injection do not confer protection against impairment of renal function under these conditions in this model of myoglobinuric-ARF.     

Clinical role of additional adjuvant chemotherapy in patients with locally advanced urothelial carcinoma following neoadjuvant chemotherapy and cystectomy

Purpose

Neoadjuvant chemotherapy (NAC) can downstage invasive bladder cancers prior to radical cystectomy (RC) and improve overall survival. However, the optimal management in patients with persistent non-organ confined disease (pT3–T4 and/or pN+) following RC has not been completely defined. The aim of this study was to describe outcomes associated with the use of adjuvant chemotherapy (AC) in patients with residual non-organ confined cancer at RC following NAC.

Materials and methods

Using data from a high-volume referral institution, pT3–T4 and/or pN+ patients who received NAC and then also RC were identified. Recurrence-free survival (RFS) and cancer-specific survival (CSS) were assessed with Kaplan–Meier analysis.

Results

From 2001 to 2013, 161 patients received NAC and then RC. Eighty-eight pT3–T4 and/or pN+ patients were identified. Twenty-nine (33 %) received AC. Adjuvant chemotherapy in the majority of patients was carboplatin-based (16), followed by cisplatin (8) and other, mainly taxane-containing regimens (5). The median RFS was 17.5 months in the AC and 13.7 months in the non-AC group (p = 0.78). AC remained an insignificant predictor for RFS after adjusting for pT, pN and margin status (HR 0.89, 95 % CI 0.48–1.68]). CSS was 23 and 22 months (p = 0.65) and remained insignificant after adjusting for pathologic confounders.

Conclusions

In our current study population, adjuvant conventional cytotoxic chemotherapy was not associated with significant improvements in RFS or CSS. The choice of AC regimens, and incorporation of newer treatments, may be the key for improving outcomes in this high-risk patient group.

     

Implications of mismatch repair genes hMLH1 and hMSH2 in patients with sporadic renal cell carcinoma

OBJECTIVES

To analyse the implications of DNA mismatch repair genes hMLH1 and hMSH2 in sporadic renal cell carcinoma (RCC).

MATERIALS AND METHODS

Specimens of tumour and healthy renal tissue were collected from 89 patients treated for sporadic RCC. Another 95 blood samples taken from individuals with no history of cancer were also analysed. After DNA extraction and PCR amplification, microsatellite instability (MSI) was determined using the Bethesda microsatellite panel, two exonic microsatellites of the TGFbRII and BAX genes, and the microsatellite D3S1611. The promoter methylation status of hMLH1 was investigated using the HpaII and MspI restriction enzymes. In addition, a sequencing analysis of complete coding region of hMLH1 and hMSH2 genes was performed.

RESULTS

MSI and promoter hypermethylation of hMLH1 were not detected. Interestingly, loss of heterozygosity (LOH) was common among patients with RCC, particularly in microsatellite D3S1611 (34.9%). Mutations were identified in eight patients: K618A and V716M in gene hMLH1; and I145V, G322D, and the novel mutation P349A, in gene hMSH2. The mutations also appeared in healthy renal tissue and therefore, were considered as germline DNA sequence variations. There were G322D and K618A changes in >1% of the healthy control subjects, suggesting that they are DNA polymorphisms.

CONCLUSIONS

Our data show that loss of function of both hMLH1 and hMSH2 is not involved in sporadic RCC, either by promoter methylation or mutation in their exons. However, LOH indicated that chromosomal instability affecting large fragments of DNA was the main genetic alteration we detected associated with RCC.     

Reconstruction of the distal radius facet by a free vascularized osteochondral autograft: anatomic study and report of a patient

PURPOSE: Large chondral defects of the distal radius after fractures present a reconstructive challenge. The purpose of this study was to present the anatomic findings from a cadaver of a vascularized osteochondral autograft taken from the third metatarsal appropriate for reconstructing the distal radius articular facet. A patient is presented in whom 70% of the scaphoid fossa was reconstructed with this technique. METHODS: The base of the third metatarsal was studied in the feet of 20 cadavers. The size and shape of the cartilage were measured. Additionally vessel distribution was recorded and the diameters of vascular foramina were measured with Juch's method. RESULTS: The base of the third metatarsal is pear shaped and is wider dorsally than plantarly. It averages 19.2 mm long on its main axis. Its cartilaginous surface is minimally concave or flat and it is slanted slightly proximal-dorsal to distal-plantar and proximal-peroneal to distal-tibial. Nutrient foramina were found in every case in the dorsum and on both sides of the proximal shaft. At least 1 nutrient vessel could be tracked back to the dorsalis pedis in every dissected specimen. CONCLUSIONS: The anatomic features of the base of the third metatarsal make it a potential vascularized autograft to consider for osteochondral defects of the distal radius.     

Maffucci's syndrome. Case reports and literature review

Maffucci syndrome is a rare, congenital disease, which is associated with the appearance of multiple enchondromas (possibility of malignant transformation in 20 to 100%), soft tissue hemangiomas and other mesenchymatous injuries. Case 1 is a 33-year-old female who presented with multiple nodules predominantly in upper extremities. Upon examination, there was deformity in articulation and nodules on the hands, which were soft and moveable. There were bony shavings in the second and fourth fingers of the left hand (enchondromas and atypical cells associated with hemangioma esclerosante). Maffucci syndrome was diagnosed. Later, excision of subcutaneous nodules in superior extremities was performed along with excision of nodules in both hands and hypochondrium (enchondroma injuries of left hand and hypochondrium, hemangioma in right hand). There was dysarticulation of the second finger at the metacarpal level of the phalanges of the left hand (chondrosarcoma). The patient is being followed up currently. Case 2 is a 26-year-old female. The patient had a history of subcutaneous abdominal tumor, exostosis, nodules and nodule in right breast. Upon examination, a tumor was found in the right breast, exostosis of right tibia, injury to the right wrist and left thyroid nodule. A simple mastectomy and axillary dissection was performed (fibroadenoma to intracanalicular and 14 negative lymph nodes). Later, left thyroidectomy and lumpectomy in right wrist were performed (hyperplasia to nodular thyroid and hemangioma cavernous). There was injury in the carpus of the right hand and elbow (hemangioma cavernous and synovial tissue with fibrosis and enchondroma). A diagnosis was made of Marffucci syndrome associated with mesenchymatous tumors. The patient was in poor general health and did not survive this hospitalization.     

The mechanism of microsatellite instability is different in synchronous and metachronous colorectal cancer

MLH1 promoter hypermethylation has been described as the primary mechanism for high-frequency microsatellite instability (MSI-H) in sporadic colorectal cancers (CRCs). The underlying molecular mechanism for microsatellite instability (MSI) in synchronous and metachronous CRCs is not well described. A total of 33 metachronous CRC patients and 77 synchronous CRC patients were identified from 2884 consecutive patients undergoing cancer surgery in an academic center. Evaluable tumors were tested for MSI, immunohistochemistry for MLH1 and MSH2 protein expression, and hypermethylation of the MLH1 promoter. MSI-H tumors were found in 12 (36%) metachronous CRC patients and 29 (38%) synchronous CRC patients. MSI-H metachronous CRC patients were younger at index cancer diagnosis (64 vs. 76 years, P = 0.01) and more often were diagnosed before 50 years of age (4 of 12 vs. 0 of 29, P = 0.005). Loss of MLH1 expression associated with promoter hypermethylation was common in all patients, although more common in MSI-H synchronous patients (50% metachronous vs. 83% synchronous, P = 0.03). Overall, MLH1 promoter hypermethylation was seen in 7 of 17 (41%) metachronous and 44 of 54 (81%) synchronous MSI-H CRCs tested (P = 0.004). Although MSI occurred with equal frequency among patients with synchronous and metachronous CRCs, the underlying mechanism for MSI was different. Observed differences in MLH1 promoter hypermethylation and patient characteristics suggest most MSI-H synchronous CRCs in our population were sporadic in origin. In contrast, more MSI-H metachronous CRCs were associated with patient and tumor characteristics suggestive of underlying hereditary nonpolyposis CRC. Presented as a poster at Digestive Disease Week 2001, Atlanta, Georgia, May 20–23, 2001.     

Single versus sequential fine-needle aspiration biopsy in the management of thyroid nodular disease.

Fine-needle aspiration biopsy (FNAB) is considered a safe, reliable and cost-effective means of selecting thyroid nodules with risk for malignancy. However, there are limitations of this method including false positive/negative and "nondiagnostic" results that may be reduced by repeating FNAB. OBJECTIVE: To evaluate accuracy, sensitivity, specificity and costs of sequential FNAB in the management of thyroid nodular disease. METHODS: Charts of all patients who underwent thyroidectomy at a university teaching hospital in Toronto from 1998 to 2000 were reviewed. FNAB reports of "suspicious for malignancy," "follicular lesion" and "cellular atypia" were considered to be positive. Data were analyzed with chi2 and z tests. RESULTS: There were 268 patients (225 women and 43 men; age range 18-89 yr; mean age 47 yr) who underwent a total of 449 FNABs (mean 1.7 FNABs/patient) within a year before thyroidectomy. Accuracy (63.8%), sensitivity (73.8%) and specificity (69%) were determined for single FNABs. Sequential FNAB increased the accuracy of method by 22.6%, sensitivity by 13.8% and specificity by 6.2%, with reduction of false positive/negative results by 14.2% and "nondiagnostic" results by 100%. However, the costs of sequential cytology per patient were 70% higher than single FNAB. CONCLUSIONS: Multiple FNABs are unpleasant for patients, but useful in the selection for treatment of patients with thyroid nodular diseases. Although sequential FNAB increases the costs of method, the improvement of precision of FNAB may imply a reduction in overall health-care costs.     

Obstructive Uropathy Secondary to Ureteral Herniation in a Pediatric En Bloc Renal Graft

Ureteral herniation is a rare entity. We report the first case of extraperitoneal ureteral herniation in a pediatric en bloc renal graft causing obstructive uropathy. A 70-year-old, obese patient with an en bloc renal transplant was found to have ureterohydronephrosis in the right renal graft on magnetic resonance imaging. Nephrostomy with insertion of a double-J catheter confirmed the presence of a ureteral loop within the inguinal tract. Surgery confirmed herniation of the ureter through the internal inguinal ring, crossing over the spermatic cord. We performed release, resection, ureteral reimplantation and hernioplasty. Four months later, renal function was normal and urinary tract dilation had diminished. This case illustrates an unusual cause of obstructive uropathy in a transplanted kidney. Apart from obesity, two other factors may have contributed to its development: presence of a redundant ureter, and the fact that the ureter had been placed over, rather than under, the spermatic cord.     

Postmenopausal intestinal obstructive endometriosis: case report and review of the literature

CONTEXT: Endometriosis is characterized by the presence of endometrial tissue outside the uterine cavity, which is commonly detected in gynecological practice but rarely reported as a coloproctological disorder. The objective of the present report was to discuss a rare case of postmenopausal intestinal endometriosis simulating a malignant lesion, following a review of the literature. CASE REPORT: A 74-year-old woman with complaints of hematochezia and tenesmus of two months' duration accompanied by liquid feces and pelvic pain, but with no other gastrointestinal or gynecological complaints, was referred to our service. She had been menopausal for 22 years, with no hormone replacement treatment, and had undergone panhysterectomy three years before the referral to us, due to endometrial thickening and a right adnexal cyst. Five months before this referral, she had undergone laparotomy due to acute obstructive abdomen, which revealed a tumor mass involving the small bowel. Anatomopathological examination of the enterectomy suggested a hypothesis of intestinal endometriosis. A proctological examination was normal. Computed tomography of the pelvis revealed thickening of the rectosigmoid transition and colonoscopy revealed friable tumor formation in the rectum. A biopsy of the lesion revealed mucosal fragments of endometrial type, which led to a review of the previous anatomopathological examination. The patient underwent rectosigmoidectomy with protective transversotomy, with a good postoperative course, and anatomical examination confirmed the intestinal endometriosis. The patient subsequently suffered a stenosing recurrence of the lesion and has undergone colostomy since then.