Evaluating the mobility of toxic metals in untreated industrial wastewater sludge using a BCR sequential extraction procedure and a leaching test

The distribution and speciation of toxic metals in industrial wastewater sludge (IWS) was investigated. In this work, the modified BCR three-stage sequential extraction procedure was applied to the fractionation of Cr Pb Ni, and Cd in untreated industrial wastewater sludge from industrial sites in Hyderabad (Pakistan). The extracts were analyzed using electrothermal atomic absorption spectrometry. The procedure was evaluated using a certified reference material for soil mixed with sewage sludge BCR 483. The results from the partitioning study indicate that more easily mobilized forms (acid exchangeable) of Cd were dominant. The oxidizable fraction was dominant for all four toxic metals. Metal recovery was good, with <4% difference between the total metal recovered through the extractant steps and the total metal determined after microwave digestion. Lixiviation tests (DIN 38414-S4) were used to evaluate the leaching of toxic species from IWS, and it was observed that levels of leachable toxic metals were low compared to the amount of metal extracted in the exchangeable fraction of the BCR protocol.

Neonatal 5HT activity antagonizes the masculinizing effect of testosterone on the luteinizing hormone release response to gonadal steroids and on brain structures in rats

Hypothalamic 5HT concentrations are transiently lower in male compared to female Wistar rats in the second week post partum (pp) and our previous findings have shown that pharmacologically potentiating 5HT activity over this period feminizes certain aspects of sexually differentiated behaviours in adult males and androgenized females. In order to investigate whether neonatal testosterone and 5HT interact to influence physiological and morphological brain sexual differences, females, androgenized females and males were treated with the 5HT2 agonist (-) [2,5 dimethoxy-4-iodophenyl]-2-amino propane HCl [(-) DOI], over days 8-16 pp. In androgenized females (250 microg testosterone proprionate, day 2 pp) (-) DOI prevented the delay in vaginal opening, but did not prevent the androgen-induced constant oestrus in females treated with 100 microg TP, day 2 pp. (-) DOI overcame the neonatal androgen effect in suppressing the positive feedback of ovarian steroids in a few males and androgenized females. (-) DOI had a feminizing effect on the volume of the anteroventral periventricular nucleus (normally smaller in males), by significantly increasing its volume in male and androgenized females. It also had a significant antagonistic effect on the testosterone-induced increase in the volume of the sexually dimorphic nucleus of the preoptic area in males and androgenized females. These findings support the view that raised 5HT activity in the second week of life antagonizes the masculinizing effect of neonatal testosterone.

A validated HPLC assay for simultaneous analysis of salmon calcitonin and duck ovomucoid

A highly sensitive and selective analytical HPLC method is reported for the simultaneous measurement of salmon calcitonin (sCT) and its enzyme inhibitor, duck ovomucoid (dOVM). The method used a reversed phase C-18 column (4.6 x 250 mm, 5 microm) at room temperature. The elution was achieved using a gradient technique (20-35% B for 10 min, 35-37% B from 10th to 20th min and 37-20% B from 20th to 25th min). The mobile phase used was 0.05% v/v trifluoroacetic acid (TFA) in water and 0.05% v/v TFA in acetonitrile with a flow rate of 1 ml/min. Detection was carried out by UV spectrophotometry at 210 nm. sCT and dOVM were eluted at 7.8 and 15.4 min respectively, free from any interfering endogenous peaks during a run time of 25 min. Linear relationships were observed between the detector response and the concentrations of the analytes (10-100 microg/ml for CT (r2 = 0.996) and 10-100 microg/ml for the dOVM (r2 = 0.999)). The assay was found to be highly selective and sensitive due to the absence of any interfering peaks. The lower C.V. and % error values of the assay indicates that the assay could accurately and precisely quantitate both sCT and dOVM in the examined concentration range. This method can be usedfor the simultaneous quantitative analysis of sCT and dOVM.

Central orexin A has site-specific effects on luteinizing hormone release in female rats

Orexin A stimulates GnRH release from hypothalamic explants in vitro. The sites of action of orexin A in the regulation of LH release have been investigated in vivo in ovariectomized rats that were given vehicle or estradiol benzoate (EB), with or without an injection of progesterone 48 h later. Orexin A was administered intrahypothalamically under Saffan anesthesia, 50 h after the EB or vehicle; its effects on plasma LH levels were monitored in sequential blood samples. Orexin A (1.0 microg/side) injected into the rostral preoptic area (rPOA) at the level of the organum vasculosum of the lamina terminalis had a stimulatory effect on LH release in EB-treated ovariectomized rats. When orexin A was injected into the medial POA (mPOA) or the arcuate/median eminence, it had an inhibitory effect on the LH surge that occurs in ovariectomized rats primed with EB plus progesterone. Orexin A injected into the mPOA also reduced LH levels in ovariectomized rats untreated with ovarian steroids. Both the stimulatory and inhibitory effects of orexin A were antagonized by SB334867A, a selective orexin 1 receptor antagonist. Furthermore, when given alone into the rPOA, this antagonist attenuated the LH surge induced by EB plus progesterone. Thus, orexin appears to have a dual effect on LH release, being stimulatory in the rPOA and inhibitory in the mPOA or arcuate/median eminence. Both effects may be mediated, at least in part, by the orexin 1 receptor. Double label immunohistochemistry revealed close appositions between orexin A immunoreactive varicosities and a small proportion of GnRH cell bodies in the rPOA. It is suggested that the stimulatory effect of orexin A on LH release may involve direct actions on GnRH neurons.

Regulatory mechanisms of viral hepatitis B and C

Of all the hepatitis viruses, only the hepatitis B virus (HBV) and hepatitis C virus (HCV) cause chronic hepatitis, which can progress to cirrhosis and hepatocellular carcinoma. In this review, we discuss how these two biologically diverse viruses use common pathways to induce oxidative stress and activation of key transcription factors, known to be involved in inflammatory processes in cells. Activation of NF-kB and STAT-3 most likely contribute to the progression of viral infections to chronic hepatitis and liver oncogenesis associated with HBV and HCV infections. In this review, we focus on the mechanisms of action of HBx and HCV NS5A proteins in inducing intracellular events associated with the viral infections.

Quantitative MRI detects abnormalities in relatives of patients with epilepsy and malformations of cortical development

Malformations of cortical development (MCD) are a common etiology for epilepsy. Laminar heterotopia, bilateral subependymal heterotopia, and lissencephaly have a genetic basis. No gene mutations have yet been identified in patients with focal cortical dysplasias. The aim of this study was to use quantitative morphometric tools to determine if there were gray matter abnormalities in relatives of patients with MCD. We studied 19 relatives of 13 probands with MCD and 58 healthy controls with high-resolution MRI. The relatives and controls had no neocortical abnormalities on visual inspection. MRI data were analyzed with voxel-based morphometry and autoblock analysis. Voxel-based morphometry showed significant increases of gray matter in 9 of 10 probands, 5 of 19 relatives, and 5 of 58 controls. The autoblock analysis showed significant abnormalities in 7 of 8 probands, 8 of 19 relatives, and 2 of 57 controls. This finding suggests structural abnormality in the brains of a greater number of relatives of MCD patients than would be expected, and in the context, a reasonable inference is that this reflects subtle genetically determined cerebral abnormalities, although acquired pathologies are possible and are not excluded.

Mitochondrially associated hepatitis B virus X protein constitutively activates transcription factors STAT-3 and NF-kappa B via oxidative stress

The hepatitis B virus X protein (HBx) plays essential roles in viral replication and the generation of hepatocellular carcinoma. In spite of a large number of suggestive cellular targets and functions, a clear picture of its mechanism(s) of action has remained elusive. In this report, we continue to characterize its recently described mitochondrial association and further examine its impact on mitochondrial functions. HBx was previously shown to bind to a voltage-dependent anion channel (VDAC3) and alter the mitochondrial transmembrane potential (Delta Psi(m)). Here we show that, as a consequence of association with mitochondria, HBx constitutively induces activation of transcription factors, which include STAT-3 and NF-kappa B. This induction of activation was sensitive to the antioxidants N-acetyl L-cysteine and pyrrolidine dithiocarbamate, as well as to overexpression of Mn-superoxide dismutase. These results therefore implicate a potential role of reactive oxygen species (ROS) in a process that ultimately leads to the activation of STAT-3 and NF-kappa B. Evidence is also presented for the HBx-induced generation of ROS. The ability of HBx to induce the activation of STAT-3 and NF-kappa B was demonstrated by mobility shift and reporter gene expression assays with lysates from HBx-transfected HepG2 cells. A C-terminal HBx deletion mutant, HBx Delta 99, failed to bind VDAC3 and activate STAT-3 and NF-kappa B. These studies shed new light on the physiological significance of HBx's mitochondrial association and its role in inducing oxidative stress which can contribute to the liver disease pathogenesis associated with the hepatitis B virus infection.

Human hepatitis C virus NS5A protein alters intracellular calcium levels, induces oxidative stress, and activates STAT-3 and NF-kappa B

The nonstructural protein 5A (NS5A) encoded by the human hepatitis C virus RNA genome is shown here to induce the activation of NF-kappaB and STAT-3 transcription factors from its cytoplasmic residence via oxidative stress. NS5A causes the disturbance of intracellular calcium. Ca2+ signaling triggers the elevation of reactive oxygen species in mitochondria, leading to the translocation of NF-kappaB and STAT-3 into the nucleus. Evidence is presented for the constitutive activation of STAT-3 by NS5A. In the presence of antioxidants [pyrrolidine dithiocarbamate (PDTC), N-acetyl l-cysteine (NAC)] or Ca2+ chelators (EGTA-AM, TMB-8), NS5A-induced activation of NF-kappaB and STAT-3 was eliminated. These results provide an insight into the mechanism by which NS5A can alter intracellular events relevant to liver pathogenesis associated with the viral infection.

Intrathecal fentanyl-induced pruritus is more severe in combination with procaine than with lidocaine or bupivacaine

BACKGROUND AND OBJECTIVES

Fentanyl is used as an additive to prolong intrathecal anesthesia with both lidocaine and low-dose bupivacaine in the outpatient setting to minimize voiding or discharge delays. Pruritus is the most common side effect. When using procaine as a substitute for lidocaine, we perceived an increased frequency and severity of pruritus. We compared prospectively the frequency and severity of itching with combinations of fentanyl with lidocaine, bupivacaine, and procaine.

METHODS

After institutional review board approval, 135 patients requesting neuraxial anesthesia were asked to evaluate the presence and severity (using a 100 point verbal pruritus score [VPS]) of itching 30 minutes after injection of their spinal anesthetic, on arrival to the postanesthesia care unit (PACU), and at the time of resolution of their block. Choice of anesthetic drug and dose and the use of intravenous sedation was left to the discretion of the attending and resident anesthesiologist.

RESULTS

Thirty-three patients received lidocaine and fentanyl, 47 received bupivacaine and fentanyl, and 55 received procaine and fentanyl. In the lidocaine group, 21% of patients experienced pruritus compared with 55% of the bupivacaine group and 55% of the procaine group (P =.003). The average VPS at 30 minutes postblock was 18.4 in the procaine group compared with 0 and 5.5 in the lidocaine and bupivacaine groups (P =.06). On admission to the PACU, it was 37 compared with 16 and 20 for lidocaine and bupivacaine, respectively (P =.006).

CONCLUSION

Procaine produces a higher frequency of pruritus than that seen with lidocaine-fentanyl combinations and a greater severity of pruritus than seen with lidocaine-fentanyl and bupivacaine-fentanyl spinal anesthesia. Reg Anesth Pain Med 2001;26:252-256.

MRSA colonization and the risk of MRSA bacteraemia in hospitalized patients with chronic ulcers

A cohort study of patients with chronic ulcers was performed to estimate the risk of methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia in a population colonized with MRSA. During a five-year period (January 1990-May 1995), 911 patients with chronic ulcers (CU), as determined by ICD9-CM code search, were admitted to an acute care hospital. Sixty percent (545/911) of these patients with CU had their CU cultured to detect MRSA and 30% (166/545) of these were colonized with MRSA. Among patients with surveillance cultures, those with MRSA colonization had significantly more days of hospitalization and were also more likely to have a central venous catheter during hospitalization compared with patients without MRSA colonization. MRSA bacteraemia occurred in 4% (36/911) of CU patients during the study period and in 6% (32/545) of cultured CU patients. Among the 545 patients who had surveillance cultures, the risk ratio for MRSA bacteraemia when there was MRSA colonization of their chronic ulcer was 16 (95% CI 6-45). Among patients with MRSA colonization, central venous catheter use was the only significant risk factor for MRSA bacteraemia. In 16 of the 28 patients with MRSA bacteraemia and MRSA colonization, the MRSA colonization was identified more than seven days before the bacteraemia. This cohort study identifies MRSA colonized CU patients in an acute care setting as a high-risk population for MRSA bacteraemia.

Demonstration of functional requirement of polypyrimidine tract-binding protein by SELEX RNA during hepatitis C virus internal ribosome entry site-mediated translation initiation

Polypyrimidine tract-binding protein (PTB) has been previously shown to physically interact with the hepatitis C virus (HCV) RNA genome at its 5'- and 3'-noncoding regions. Using high affinity SELEX RNA molecules, we present evidence for the functional requirement of PTB during HCV internal ribosome entry site (IRES)-controlled translation initiation. This study was carried out in rabbit reticulocyte translation lysates in which the HCV IRES-driven reporter RNA was introduced along with the PTB-specific SELEX RNA molecules. The SELEX RNAs specifically inhibited the HCV IRES function in the context of mono- and dicistronic mRNAs. The cap-dependent translation of a reporter (chloramphenicol acetyltransferase) RNA or naturally capped brome mosaic virus RNA, however, was not affected by the presence of SELEX during in vitro translation assays. The SELEX-mediated inhibition of the HCV IRES is shown to be relieved by the addition of recombinant human PTB in an add-back experiment. The in vivo requirement of PTB was further confirmed by cotransfection of Huh7 cells with reporter RNA and PTB-specific SELEX RNA. The HCV IRES activity was inhibited by the SELEX RNA in these cells, but not by an unrelated control RNA. Together, these results demonstrate the functional requirement of cellular PTB in HCV translation and further support the feasible use of SELEX RNA strategy in demonstrating the functional relevance of cellular protein(s) in complex biological processes.

Serotonin inhibits luteinizing hormone release via 5-HT1A receptors in the zona incerta of ovariectomised, anaesthetised rats primed with steroids

The zona incerta (ZI), an area in the dorsal hypothalamus, contains neuronal systems that appear to control gonadotropin release. Previous findings show that there is an inverse relationship between serotonin (5-HT) activity in the ZI and plasma luteinizing hormone (LH) levels, indicating that the 5-HT system in this area has an inhibitory effect on LH release. Employing anaesthetised, ovariectomised rats primed with 5 microg oestradiol benzoate followed at 48 h by 0.5 mg progesterone, we have shown that 2 microg/side 5-HT in the ZI inhibits the LH surge that normally occurs 4 h after the progesterone treatment. This effect was mimicked by 2 microg/side 8-OH-DPAT, a 5-HT1A agonist, but not by DOI, a 5-HT2 agonist, BMY7378, a presynaptic 5-HT1A agonist or MCPP, a 2B & 2C agonist. The inhibitory effect of 5-HT and 8-OH-DPAT was prevented by pretreatment, 1 h before, with either 2 mg/kg i.p. WAY100135, a 5-HT1A antagonist or 0.25 mg/kg i.p. ritanserin, a 5-HT2 antagonist. These results indicate that 5-HT in the ZI exerts its inhibitory effect on LH release via 5-HT1A receptors but that another 5-HT subtype may also be involved.

A novel mutation in the mitochondrial tRNA(TYr) gene associated with exercise intolerance

The authors report a novel A5874G mutation in the mitochondrial tRNA tyrosine (tRNA(TYr)) gene associated with exercise intolerance, limb weakness, and complex III deficiency. The mutation was absent in blood from the patient and all maternal family members, indicating that it may be a spontaneous somatic mutation in muscle. This is the first point mutation in the tRNA(TYr) gene associated with human disease and is further evidence that exercise intolerance associated with complex III deficiency is genetically heterogeneous.

Human La antigen is required for the hepatitis C virus internal ribosome entry site-mediated translation

The 5'-noncoding region (5'-NCR) of the hepatitis C virus (HCV) RNA genome serves as an internal ribosome entry site (IRES) and mediates translation initiation in a cap-independent manner. Previously, we reported the interaction between La antigen and the HCV IRES, which appeared to occur in the context of initiator AUG. It was further shown that HCV IRES-mediated translation was stimulated in the presence of human La antigen. In this study, we have defined the cis- and trans-acting elements responsible for La-5'-NCR interactions and established the dependence of the HCV IRES efficiency on cellular La antigen. During the La-IRES interaction, initiator AUG but not the neighboring codons was found to be the direct target of La binding. The C terminus effector domain-dependent modulation of La binding to the HCV IRES is demonstrated by deletion and substitution mutagenesis of the protein. An RNA systematic evolution of ligands by exponential enrichment (SELEX), generated against La protein that selectively binds La in HeLa lysates and competes for the protein binding to the 5'-NCR, was used to demonstrate the requirement of La for the HCV IRES function in the context of mono- and dicistronic mRNAs. Sequestration of La antigen by the RNA SELEX in HeLa translation lysates blocked the HCV and poliovirus IRES-mediated translation in vitro. The functional requirement of La protein for the HCV IRES activity was further established in a liver-derived cell line and in an add-back experiment in which the inhibited IRES was rescued by recombinant human La. These results strongly argue for the novel role of La protein during selection of the initiator AUG and its participation during internal initiation of translation of the HCV RNA genome.

Does maternal prenatal attachment predict postnatal mother-infant interaction?

The current study examined whether maternal prenatal attachment is associated with the mother-infant relationship. One hundred pregnant women and their infants at 12 weeks participated in the study. The sample was part of the Umeâ Child and Family Development project and was randomly recruited by midwives or health visitors. The expectant women completed a self-administered questionnaire, the PAI (the Prenatal Attachment Inventory) measuring prenatal attachment towards their unborn baby. At about 12 weeks postpartum, mothers and their infants were observed and videotaped during an en face interaction. The results revealed that maternal prenatal attachment towards the unborn baby is a good predictor of the early mother-infant relationship. Mothers who were high on the PAI-factor fantasy, for example, in general showed more involvement while interacting with their babies. Mothers rated highly on PAI-factors such as interaction and affection stimulated their infants by using more proximal stimulation, while those rated highly on differentiation of self with the unborn baby used more distal stimulation. Maternal responsive behaviour was only predicted by infant attentive behaviour. This study demonstrated that maternal prenatal attachment during the third trimester of pregnancy is associated with the postnatal maternal involvement, and can serve as an important diagnostic aid in identifying those women for whom the mother-child interaction is likely to be sub-optimal.

Does maternal prenatal attachment predict postnatal mother-infant interaction?

The current study examined whether maternal prenatal attachment is associated with the mother-infant relationship. One hundred pregnant women and their infants at 12 weeks participated in the study. The sample was part of the Umeâ Child and Family Development project and was randomly recruited by midwives or health visitors. The expectant women completed a self-administered questionnaire, the PAI (the Prenatal Attachment Inventory) measuring prenatal attachment towards their unborn baby. At about 12 weeks postpartum, mothers and their infants were observed and videotaped during an en face interaction. The results revealed that maternal prenatal attachment towards the unborn baby is a good predictor of the early mother-infant relationship. Mothers who were high on the PAI-factor fantasy, for example, in general showed more involvement while interacting with their babies. Mothers rated highly on PAI-factors such as interaction and affection stimulated their infants by using more proximal stimulation, while those rated highly on differentiation of self with the unborn baby used more distal stimulation. Maternal responsive behaviour was only predicted by infant attentive behaviour. This study demonstrated that maternal prenatal attachment during the third trimester of pregnancy is associated with the postnatal maternal involvement, and can serve as an important diagnostic aid in identifying those women for whom the mother-child interaction is likely to be sub-optimal.

Allergic reaction to spinal cord stimulator

OBJECTIVE

The objective was to report on the possibility of allergic reaction to the components of a spinal cord stimulator.

DESIGN

We describe a severe allergic reaction after the insertion of a spinal cord stimulator in a patient with complex regional pain syndrome type 1.

SETTING

The patient was being followed in an office-based pain management practice.

PATIENT

The patient is a 41-year-old woman with complex regional pain syndrome type 1, posttrauma.

INTERVENTION

Insertion of a cervical and lumbar spinal cord stimulator.

OUTCOME MEASURES

The outcome measures were a numerical scale of pain intensity and the ability to perform the activities of daily living.

RESULTS

Adequate pain control complicated by allergic reaction.

CONCLUSIONS

There exists a possibility that a patient may experience an allergic reaction to spinal cord stimulator components. Recognition of such contact sensitivity is important for physicians implanting such devices. Patients may be misdiagnosed as having infections, which can delay appropriate management; definitive diagnosis can be confirmed with a patch test. Treatment consists of removal of such devices.

Hepatitis B virus X protein colocalizes to mitochondria with a human voltage-dependent anion channel, HVDAC3, and alters its transmembrane potential

Understanding the mechanism(s) of action of the hepatitis B virus (HBV)-encoded protein HBx is fundamental to elucidating the underlying mechanisms of chronic liver disease and hepatocellular carcinoma caused by HBV infection. In our continued attempts to identify cellular targets of HBx, we have previously reported the identification of a novel cellular protein with the aid of a yeast two-hybrid assay. This cellular gene was identified as a third member of the family of human genes that encode the voltage-dependent anion channel (HVDAC3). In the present study, physical interaction between HBx and HVDAC3 was established by standard in vitro and in vivo methods. Confocal laser microscopy of transfected cells with respective expression vectors colocalized HVDAC3 and HBx to mitochondria. This novel, heretofore unreported subcellular distribution of HBx in mitochondria implies a functional role of HBx in functions associated with mitochondria. Using a stable cationic fluorophore dye, CMXRos, we show that HBx expression in cultured human hepatoma cells leads to alteration of mitochondrial transmembrane potential. Such functional roles of HBx in affecting mitochondrial physiology have implications for HBV-induced liver injury and the development of hepatocellular carcinoma.

Enhancing the aqueous solubility of d4T-based phosphoramidate prodrugs

A range of polyether para-substituted phosphoramidates were synthesised and found to have substantially elevated aqueous solubilities compared to the underivatised parent prodrug. A 30-fold increase in aqueous solubility could be achieved without a substantial decrease of in vitro activity against HIV-1. Replacement of the aryl (i.e. phenolic) moiety by tyrosine led to a substantial enhancement in aqueous solubility but also to a decrease in antiviral potency. A previously unobserved trend was identified, relating increased aryl substituent steric bulk to decreased antiviral activity.

Characterization of Mycobacterium tuberculosis isolates from patients in Houston, Texas, by spoligotyping

Mycobacterium tuberculosis isolates (n = 1,429) from 1,283 patients collected as part of an ongoing population-based tuberculosis epidemiology study in Houston, Texas, were analyzed by spoligotyping and IS6110 profiling. The isolates were also assigned to one of three major genetic groups on the basis of nucleotide polymorphisms located at codons 463 and 95 in the genes (katG and gyrA) encoding catalase-peroxidase and the A subunit of DNA gyrase, respectively. A total of 225 spoligotypes were identified in the 1,429 isolates. There were 54 spoligotypes identified among 713 isolates (n = 623 patients) assigned to 73 IS6110 clusters. In addition, among 716 isolates (n = 660 patients) with unique IS6110 profiles, 200 spoligotypes were identified. No changes were observed either in the IS6110 profile or in the spoligotype for the 281 isolates collected sequentially from 133 patients. Five instances in which isolates with slightly different spoligotypes had the same IS6110 profile were identified, suggesting that in rare cases isolates with different spoligotypes can be clonally related. Spoligotypes correlated extremely well with major genetic group designations. Only three very similar spoligotypes were shared by isolates from genetic groups 2 and 3, and none was shared by group 1 and group 2 organisms or by group 1 and group 3 organisms. All organisms belonging to genetic groups 2 and 3 failed to hybridize with spacer probes 33 to 36. Taken together, the results support the existence of three distinct genetic groups of M. tuberculosis organisms and provide new information about the relationship between IS6110 profiles, spoligotypes, and major genetic groups of M. tuberculosis.

Incidence of neurapraxia in digital nerve injuries

Hand surgeons presented with a hand or finger laceration and an abnormal static two-point discrimination (> or =10 mm) must determine which patients require surgical exploration. There appears to be a paucity of data in the literature defining the incidence and nature of neurapraxia in this setting. A study was conducted in a busy urban practice to better understand this problem. To determine the incidence of intact nerves (i.e., neurapraxia) in digital nerve injury patients, the authors reviewed experience with 152 patients who presented with isolated digital nerve injuries over a 33-month period. Preoperative return of sensation and negative exploration cases were combined and referred to as the trauma-induced neurapraxia (TIN) group. There were 18 non-repair cases among the 152 isolated digital nerve injuries, giving a 12 percent incidence of TIN. Sensory recovery among the TIN patients ranged from 12 days to 6 months. In this study, the authors defined a group of patients who did not require surgical repair for isolated digital nerve injury as TIN cases. The TIN group represented 12 percent of the digital nerve trauma patients and required long follow-up for sensory recovery. This information is an important part of patient education and informed consent.