Does primary closure of direct inguinal hernia defect during laparoscopic mesh repair reduce the risk of early recurrence?

PURPOSE: Hernia recurrence is an important complication following inguinal hernia repair. Primary closure of ventral hernia defects laparoscopically has been shown to reduce the risk of recurrence and seroma formation. The results for ventral hernias may potentially be applied to direct inguinal hernias. Our aim was to evaluate the value of primary closure of direct defects during laparoscopic inguinal hernia mesh repair in reducing the incidence of early recurrence. METHODS: A retrospective, single-center cohort study was conducted on cases performed from August 2016 to February 2018. Patients with direct inguinal hernias undergoing elective laparoscopic mesh repair were included. When performed, the direct hernia defect was primarily closed with extracorporeal non-absorbable interrupted sutures followed by standard placement of a lightweight mesh covering myopectineal orifices. Early recurrence was defined as occurring within 1 year of surgery. RESULTS: A total of 75 direct inguinal hernias in 53 patients who underwent surgery and completed at least 1 year of follow-up were analyzed. The mean age of patients was 63 years (range 44-82 years); with majority of patients being male (98.1%). There were no significant differences observed between the two patient populations in terms of demographics, mean operative time and risk factors. In 9 (16.9%) patients, the direct hernias were recurrent hernias and all underwent open mesh repair during the index hernia surgery. The majority of hernia repairs (63 hernias in 45 patients, 85%) were performed via the totally extraperitoneal (TEP) approach. 19 patients (35.8%) with 28 direct inguinal hernias underwent primary closure of the direct defect prior to mesh placement; while, 34 patients (64.2%) with 47 direct hernias did not undergo primary closure. There were 3 direct hernia recurrences (6.4%) at 1 year post-operatively, and all occurred in the non-closure group. In comparison, there were no recurrences in the closure group; however, this difference was not statistically significant (p = 0.289) in our study due to the small sample size. CONCLUSION: Closure of direct inguinal hernia defects during laparoscopic mesh repair has been shown to reduce the incidence of early hernia recurrence in our retrospective study but future randomized controlled trials with large numbers would enable us to draw more robust conclusions and perhaps change the way we perform laparoscopic inguinal hernia repair.

Epigenetic inactivation of INK4/CDK/RB cell cycle pathway in acute leukemias.

Dysregulation of cell cycle is important in oncogenesis. We analyzed the inactivation of the INK4 family CKI/CDK/RB pathway by gene promoter hypermethylation in leukemogenesis. The methylation-specific polymerase chain reaction (MSP) with primers for methylated (M-MSP) and unmethylated (U-MSP) alleles of the p15, p16, p18, and RB genes was used to study five leukemic cell lines, 50 acute myeloid leukemia (AML) and 25 acute lymphoblastic leukemia (ALL) samples. None of the leukemic cell lines showed p18 and RB methylation. p15 was methylated in Raji, while p16 was methylated in U937 and Raji. In NB4 and Jurkat, both alleles of p15 and p16 appeared to be deleted. At diagnosis, p15 methylation occurred in 29 (58%) AML patients, and 10 (40.0%) ALL patients. p16 methylation occurred in two (4%) AML and two (8%) ALL patients. Only one each of AML and ALL patients had concurrent p15 and p16 methylation. None of the patients had methylation of p18 or RB. In AML, p15 methylation was associated with M2 subtype ( p=0.018). Patients with and without p15 methylation had similar complete remission (CR) rates and projected 5-year overall survival (OS) or disease-free survival (DFS). Therefore, methylation inactivation of the INK4/CDK/RB pathway in leukemia involved primarily p15 and occasionally p16, but not p18 or RB. In AML, p15 gene methylation was associated with the M2 subtype, but was not prognostic for CR, OS, or DFS.

Absence of p300 gene promoter methylation in acute leukemia.

p300 is a widely expressed transcriptional coactivator, and is involved in DNA repair, cell growth, differentiation, and apoptosis. Recent data suggest that it may function as a tumor suppressor. We investigated the frequency of aberrant methylation of p300 promoter in seven leukemic cell lines, as well as in the diagnostic samples of 46 patients with acute myelocytic leukemia (11 with M1, 22 with M2, 3 with M4, and 1 with M5), 24 patients with acute promyelocytic leukemia, and 22 patients with acute lymphoblastic leukemia (3 with T-cell, 1 with pre-B, 2 with Burkitt, 2 with early B-precursors, and 14 with common). None of the cell lines and patient samples showed p300 gene methylation. Therefore, hypermethylation of p300 is not an important mechanism in leukemogenesis.

High frequency of polyoma BK virus shedding in the gastrointestinal tract after hematopoietic stem cell transplantation: a prospective and quantitative analysis.

The polyoma BK virus (BKV) remains latent after primary infection and may reactivate during immunosuppression. The uroepithelium is the main latency site defined. This study addressed whether the gastrointestinal tract might be another latency site. To test this hypothesis, we prospectively quantified fecal BKV by quantitative PCR reaction in 40 patients undergoing hematopoietic SCT (HSCT). Urinary BKV was similarly quantified. Fecal BKV excretion was positive in 16/40 patients, of whom 10 were transient (<3 consecutively positive samples), six were persistent (> or =3 consecutively positive samples) and three were persistent with peaking (> or =10(3)-fold increase in viral load over baseline, reaching 5.11 x 10(6), 4.68 x 10(7) and 2.75 x 10(8) copies/sample at 14, 14 and 21 days post-HSCT, respectively). Urinary BKV excretion was positive in 25/40 patients. Fecal BKV excretion was significantly correlated with that of the urine (P=0.036) and was significantly associated with allogeneic HSCT (P=0.037) and persistent and peaking of urinary BKV excretion (P<0.001). Binary logistic regression showed that BKV viruria was the only significant risk factor for fecal BKV excretion (P=0.021). Fecal BKV excretion occurred in 40% patients undergoing HSCT, implicating the gastrointestinal tract as a BKV latency site.

Aminorex and rexamino as metabolites of levamisole in the horse.

Administration studies of levamisole in horses were carried out using two different levamisole preparations, namely, levamisole hydrochloride oral bolus and levamisole phosphate injectable solution. These preparations were analysed in detail for the presence of aminorex-like impurities. Both levamisole preparations were found to contain 1-(2-mercaptoethyl)-4-phenyl-2-imidazolidinone (I) and 4-phenyl-2-imidazolidinone (II) as degradation impurities, but neither aminorex nor rexamino was detected in these preparations. After the administration of these preparations to horses, aminorex, rexamino, in addition to levamisole and compound II, were detected in post-administration urine and plasma samples, among which compound II was found to have the longest detection time. Administration study of compound II was then performed on another horse to investigate whether it could be a metabolic precursor of aminorex and/or rexamino. However, no aminorex and rexamino was detected in the post-administration samples, suggesting that compound II was not a metabolic precursor of aminorex or rexamino. A metabolite (III) of compound II, tentatively identified to be a hydrolysis product of compound II, was observed instead. It has been established unequivocally that the normal use of levamisole products in horses can lead to the presence of aminorex, rexamino and 4-phenyl-2-imidazolidinone (II) in their urine and blood samples. As compound II has the longest detection time, the detection of aminorex (and in some cases rexamino) in some of the official samples from racehorses can be ascribed to the use of levamisole products as long as compound II is also present as a marker. These findings should be of direct relevance to the investigation of some of the cases of aminorex detection in official doping control samples from racehorses.

Metabolic studies of turinabol in horses.

Turinabol (4-chloro-17alpha-methyl-17beta-hydroxy-1,4-androstadien-3-one) is a synthetic oral anabolic androgenic steroid. As in the case of other anabolic steroids, it is a prohibited substance in equine sports. The metabolism of turinabol in human has been reported previously; however, little is known about its metabolic fate in horses. This paper describes the studies of both the in vitro and in vivo metabolism of turinabol in racehorses with an objective to identify the most appropriate target metabolites for detecting turinabol administration. For the in vitro studies, turinabol was incubated with fresh horse liver microsomes. Metabolites in the incubation mixture were isolated by liquid-liquid extraction and analysed by gas chromatography-mass spectrometry (GC-MS) after trimethylsilylation. The results showed that the major biotransformation of turinabol was hydroxylation at the C6, C16 and C20 sites to give metabolites 6beta-hydroxyturinabol (M1), 20-hydroxyturinabol (M2), two stereoisomers of 6beta,16-dihydroxyturinabol (M3a, M3b) and 6beta,20-dihydroxyturinabol (M4). The metabolite 6beta-hydroxyturinabol was confirmed using an authentic reference standard. The structures of all other turinabol metabolites were tentatively identified by mass spectral interpretation. For the in vivo studies, two horses were administered orally with turinabol. Pre- and post-administration urine samples were collected for analysis. Free and conjugated metabolites were isolated using solid-phase extraction and analysed by GC-MS as described for the in vitro studies. The results revealed that turinabol was extensively metabolised and the parent drug was not detected in urine. Two metabolites detected in the in vitro studies, namely 20-hydroxyturinabol and 6beta,20-dihydroxyturinabol, these were also detected in post-administration urine samples. In addition, 17-epi-turinabol (M5) and six other metabolites (M6a-M6c and M7a-M7c), derived from D-ring hydroxylation and A-ring reduction, were also detected. Except for 17-epi-turinabol, none of these metabolites has ever been reported in any species. All in vivo metabolites were detected within 48 h after administration.

Epigenetic inactivation of the CIP/KIP cell-cycle control pathway in acute leukemias.

Dysregulation of the cell cycle is important in oncogenesis. We analyzed the potential inactivation of the CIP/KIP family of the cyclin E/CDK/RB pathway by gene promoter hypermethylation in leukemias. The methylation-specific polymerase chain reaction (MSP) with primers for methylated (M-MSP) and unmethylated (U-MSP) alleles of the p21, p27, and p57 genes was used to study five leukemic cell lines, 50 acute myeloid leukemia (AML) samples, and 25 acute lymphoblastic leukemia (ALL) samples. p21 was hemizygously methylated in Raji and Jurkat but remained unmethylated in U937, HL60, and NB4. p27 was hemizygously methylated in Raji but unmethylated in the other cell lines. p57 was completely methylated in Raji and NB4, hemizygously methylated in U937, and unmethylated in HL60 and Jurkat. At diagnosis, p21 methylation was not detected in any case of AML or ALL. p27 methylation occurred in 2 (4%) AML patients and in 1 (4%) ALL patient. p57 methylation occurred in 1 (2%) AML patient and in 1 (4%) ALL patient. Therefore, methylation inactivation of the INK4/CDK/RB pathway in leukemia is infrequent. A review of the literature showed a marked variation in the frequencies of methylation of these genes, which might be attributable to difference in methodologies used to detect gene methylation.

Epigenetic dysregulation of the Jak/STAT pathway by frequent aberrant methylation of SHP1 but not SOCS1 in acute leukaemias.

SOCS1 and SHP1 are negative regulators of the Jak/STAT signalling pathway that is implicated in leukaemogenesis. We studied if aberrant methylation of SOCS1 and SHP1 might be involved in the pathogenesis and prognostication of acute leukaemias by methylation-specific polymerase chain reaction (MSP). At diagnosis, methylation of SHP1 occurred more frequently in acute myeloid leukaemia (AML) (n=26, 52%) than acute lymphoblastic leukaemia (ALL) (n=6, 24%) (p=0.02). Methylation of SOCS1 was absent in both AML and ALL patients. SHP1 methylation was not associated with specific clinicopathologic features and had no prognostic impact on AML patients. Frequent methylation of SHP1, but not SOCS1, may be important in the pathogenesis, but not prognosis, of acute leukaemias.

Infrequent hypermethylation of CEBPA promotor in acute myeloid leukaemia.

The gene CEBPA, encoding the transcription factor C/EBPalpha, is crucial for granulocyte differentiation. We investigated the frequency of aberrant CEBPA promotor methylation with the methylation-specific polymerase chain reaction in 70 patients with acute myeloid leukaemia (AML). Two patients, both with M2 morphology, were found to have methylated CEBPA. In one of them, the fusion gene AML1/ETO, reported to cause transcription repression of CEBPA, was also present, suggesting that more than one mechanism might collaborate to suppress CEBPA gene expression. Aberrant CEBPA methylation is infrequent in AML, but may occur preferentially in the M2 phenotype.

Randomized, double-blind comparison of different inspired oxygen fractions during general anaesthesia for Caesarean section.

BACKGROUND: The optimal inspired oxygen fraction FI(O(2)) for fetal oxygenation during general anaesthesia for Caesarean section is not known. METHODS: We randomized patients having elective Caesarean section to receive one of the following: FI(O(2)) 0.3, FI(N(2))(O) 0.7 and end-tidal sevoflurane 0.6% (Group 30, n=20); FI(O(2)) 0.5, FI(N(2))(O) 0.5 and end-tidal sevoflurane 1.0% (Group 50, n=20), or FI(O(2)) 1.0 and end-tidal sevoflurane 2.0% (Group 100, n=20) until delivery. Neonatal outcome was compared biochemically and clinically. RESULTS: At delivery, for umbilical venous blood, mean PO(2) was greater in Group 100 (7.6 (SD 3.7) kPa) compared with both Group 30 (4.0 (1.1) kPa, P<0.0001) and Group 50 (4.7 (0.9) kPa, P=0.002) and oxygen content was greater in Group 100 (17.2 (1.6) ml dl(-1)) compared with both Group 30 (12.8 (3.6) ml dl(-1), P=0.0001) and Group 50 (13.8 (2.6) ml dl(-1), P=0.0001). For umbilical arterial blood, PO(2) was greater in Group 100 (3.2 (0.4) kPa) compared with Group 30 (2.4 (0.7) kPa, P=0.003), and in Group 50 (2.9 (0.8) kPa) compared with Group 30 (2.4 (0.7) kPa, P=0.04); oxygen content was greater in Group 100 (10.8 (3.5) ml dl(-1)) than in Group 30 (7.0 (3.0) ml dl(-1), P<0.01). Apgar scores, neonatal neurologic and adaptive capacity scores, and maternal arterial plasma concentrations of epinephrine and norepinephrine before induction and at delivery were similar among groups. No patient reported intraoperative awareness. CONCLUSIONS: Use of FI(O(2)) 1.0 during general anaesthesia for elective Caesarean section increased fetal oxygenation.

Supplementary oxygen for elective Caesarean section under spinal anaesthesia: useful in prolonged uterine incision-to-delivery interval?

BACKGROUND: The benefit of administering supplementary oxygen during elective Caesarean section under regional anaesthesia is controversial. It has been hypothesized that its use would improve fetal oxygenation in the event of a prolonged uterine incision-to-delivery (U-D) interval. Our aim was to test this hypothesis in a prospective, randomized, double-blinded, controlled study. METHODS: We allocated randomly 204 women having elective Caesarean section under spinal anaesthesia to breathe 21, 40 or 60% oxygen. We recorded the U-D interval, umbilical arterial (UA) and venous (UV) blood gases and oxygen content and Apgar scores. Subgroup analysis was performed according to whether the U-D interval was prolonged (>180 s) or not. RESULTS: The U-D interval was <180 s in 159 patients and >180 s in 45 patients. There were no differences in UV or UA blood gases, oxygen content or Apgar scores between cases with and without a prolonged U-D interval. In cases without a prolonged U-D interval, administering 60% oxygen increased UV PO(2) (mean 4.3 (SD 1.1) vs 3.7 (1.0) kPa, P=0.003) and oxygen content (14.4 (3.3) vs 12.9 (2.7) ml dl(-1), P=0.007) compared with air. In cases with a prolonged U-D interval, administering 60% oxygen increased UV PO(2) (4.6 (0.6) vs 3.9 (0.8) kPa, P=0.019) compared with air but there was no difference in UV oxygen content. There was no increase in the UV PO(2) or oxygen content when 40% oxygen was administered compared with air. CONCLUSIONS: Supplementary oxygen did not increase fetal oxygenation in cases where the U-D interval was prolonged. Our data do not support the routine administration of supplementary oxygen during elective Caesarean section for this purpose.