Minilaparoscopic cholecystectomy versus conventional laparoscopic cholecystectomy. An endless debate

Background: Our systematic review and meta-analysis examine the impact of minilaparoscopic cholecystectomy (MLC) versus conventional laparoscopic cholecystectomy (CLC). Some authors previously compared these surgical approaches without reaching any clear conclusion, since then, further trials have been performed, but an update was needed. Materials and Methods: PubMed, EMBASE, and the CENTRAL were systematically searched for randomized controlled trials comparing MLC versus CLC up to August 2019. The outcome measures used for comparison were operative time (OT), overall morbidity, intra- and postoperative complications, conversion and reintervention rate, length of hospital stay (LOS), postoperative pain (POP), and cosmetic results. A meta-analysis of relevant studies was performed using RevMan 5.3. Results: Fifteen studies, including 863 patients, were considered eligible to collect data and entered the meta-analysis. A total of 415 patients in the MLC group versus 448 in the CLC group were compared. No statistical difference as for overall morbidity, intra- and postoperative complications, conversion and reintervention rate, LOS, and cosmetic results were retrieved among the groups. CLC results faster and MLC shows to be the least painful. Conclusions: According to the available high-level evidence, both surgical approaches resulted substantially equivalent to perform LC, with some advantages of CLC as for OT and of MLC concerning POP. As a consequence, we can conclude that either procedure is superior or inferior to the other one; actually, we are not able to suggest the adoption of any of the two on a routine basis

NO scavenging through reductive nitrosylation of ferric Mycobacterium tuberculosis and Homo sapiens nitrobindins

Ferric nitrobindins (Nbs) selectively bind NO and catalyze the conversion of peroxynitrite to nitrate. In this study, we show that NO scavenging occurs through the reductive nitrosylation of ferric Mycobacterium tuberculosis and Homo sapiens nitrobindins (Mt-Nb(III) and Hs-Nb(III), respectively). The conversion of Mt-Nb(III) and Hs-Nb(III) to Mt-Nb(II)-NO and Hs-Nb(II)-NO, respectively, is a monophasic process, suggesting that over the explored NO concentration range (between 2.5 × 10-5 and 1.0 × 10-3 M), NO binding is lost in the mixing time (i.e., NOkon ≥ 1.0 × 106 M-1 s-1). The pseudo-first-order rate constant for the reductive nitrosylation of Mt-Nb(III) and Hs-Nb(III) (i.e., k) is not linearly dependent on the NO concentration but tends to level off, with a rate-limiting step (i.e., klim) whose values increase linearly with [OH-]. This indicates that the conversion of Mt-Nb(III) and Hs-Nb(III) to Mt-Nb(II)-NO and Hs-Nb(II)-NO, respectively, is limited by the OH--based catalysis. From the dependence of klim on [OH-], the values of the second-order rate constant kOH- for the reductive nitrosylation of Mt-Nb(III)-NO and Hs-Nb(III)-NO were obtained (4.9 (±0.5) × 103 M-1 s-1 and 6.9 (±0.8) × 103 M-1 s-1, respectively). This process leads to the inactivation of two NO molecules: one being converted to HNO2 and another being tightly bound to the ferrous heme-Fe(II) atom

Reversible two-step unfolding of heme-human serum albumin: A 1H-NMR relaxometric and circular dichroism study

Human serum albumin (HSA) participates in heme scavenging, the bound heme turning out to be a reactivity center and a powerful spectroscopic probe. Here, the reversible unfolding of heme-HSA has been investigated by H-1-NMR relaxometry, circular dichroism, and absorption spectroscopy. In the presence of 6 equiv of myristate ( thus fully saturating all available fatty acid binding sites in serum heme-albumin), 1.0 M guanidinium chloride induces some unfolding of heme-HSA, leading to the formation of a folding intermediate; this species is characterized by increased relaxivity and enhanced dichroism signal in the Soret region, suggesting a more compact heme pocket conformation. Heme binds to the folding intermediate with K-d = (1.2 +/- 0.1) x 10(-6) M. In the absence of myristate, the conformation of the folding intermediate state is destabilized and heme binding is weakened [K-d = (3.4 +/- 0.1) x 10(-5) M]. Further addition of guanidinium chloride ( up to 5 M) brings about the usual denaturation process. In conclusion, myristate protects HSA from unfolding, stabilizing a folding intermediate state in equilibrium with the native and the fully unfolded protein, envisaging a two-step unfolding pathway for heme-HSA in the presence of myristate

Functional Modulation by Lactate of Myoglobin A MONOMERIC ALLOSTERIC HEMOPROTEIN

The effect of lactate on O2 binding properties of sperm whale and horse heart myoglobins (Mb) has been investigated at moderately acid pH (i.e. pH 6.5, a condition which may be achieved in vivo under a physical effort). Addition of lactate brings about a decrease of O2 affinity (i.e. an increase of P50) in sperm whale and horse heart myoglobins. Accordingly, lactate shows a different affinity for the deoxygenated and oxygenated form, behaving as a heterotropic modulator. The lactate effect on O2 affinity appears to differ for sperm whale and horse heart Mb, δlogP50 being ≈1.0 and ≈0.4, respectively. From the kinetic viewpoint, the variation of O2 affinity for both myoglobins can be attributed mainly to a decrease of the kinetic association rate constant for ligand binding