Recurrent Localized Tenosynovial Giant Cell Tumor of the Left Ring Finger: A Case Report and Literature Review

Here, we report the case of recurrent swelling and pain in the proximal interphalangeal joint of the left ring finger, which was later diagnosed as a localized tenosynovial giant cell tumor in a young adult female. The first presentation was at the same anatomical site four years prior. Examination at presentation showed a firm skin-colored nodule in the volar aspect of the left ring finger. The swelling was seen to be partly attached to underlying structures and was non-tender. After a careful physical examination and plain radiograph imaging of the hand, the two differential diagnoses considered were tenosynovial giant cell tumor and ganglion cyst. A surgical excision was performed, and histopathologic evaluation showed features consistent with a tenosynovial giant cell tumor, localized type. The resection margins were clear of tumor. The patient had no intraoperative or postoperative complications. Postoperative physiotherapy was recommended. No recurrence was seen after postoperative surgical follow-up for one year. This report highlights the importance of histopathologic evaluation and confirmation of clear surgical margins in the management of tenosynovial giant cell tumors. In recurrent cases, surgical re-excision with clear margins provides good clinical outcomes. Before surgical excision, patients should be informed about the biologic nature of the lesion and the high risk of recurrence. The management modalities to prevent recurrence and the need for long-term follow-up should also be discussed with the patient.

Gender Determination Using Index and Ring Finger Linear Measurements in North Indian Population: A Cross-Sectional Study

BACKGROUND

In the fields of medico-legal matters and bio-archaeological settings, gender evaluation plays a pivotal role in the initial stages of human identification. Approximately half of the population at risk is excluded when gender is determined, making it the most essential factor for identification. When it comes to medico-legal matters and bio-archaeological settings, gender evaluation is a crucial initial step in human identification. Traditional gender determination procedures, such as skull and pelvic analysis, may be hindered by fragmentary human remains that have been degraded by various forms of inhumation or physical assaults.

AIM

To investigate sexual dimorphism, this study examined the ratio of index finger length to ring finger length.

MATERIALS AND METHOD

The lengths of the index and ring fingers were measured and the ratios between them were calculated for both hands separately. Applications of IBM SPSS Statistics for Windows, Version 16.0 (Released 2007; IBM Corp., Armonk, New York, United States) included Student's t-test and Levene's test.

RESULTS

According to the study, women's index finger-to-ring finger length ratios were much longer than men's. The ratio of index finger to ring finger length was significantly different between the sexes on both sides of the hand (p<0.001). In terms of the right hand, the threshold value was 0.9666 for men and 0.9952 for females, while in terms of the left hand, the values were 0.9638 and 0.9920, respectively.

CONCLUSION

With an advancing front in this arena on gender determination, the use of digits has become an additional source of support to physical anthropologists for bio-archaeological surveys and to forensic experts for use in medico-legal investigations for fragmentary remains received during investigatory trials.

Thumb Reconstruction Using Transfer of the Ring Finger Without Vascular Anastomosis

PURPOSE

This study describes the results of the ring finger transfer technique for thumb reconstruction.

METHODS

Five fingers of 4 patients aged 23-57 years who presented to our clinic with an amputated thumb between 2017 and 2019 were included in this study. The results were assessed using Disabilities of Arm, Shoulder, Hand (DASH) scoring. Active range of motion, grip and pinch strengths, Kapandji scores, and static 2-point discrimination were measured.

RESULTS

The mean age of the patients (3 men, 1 woman) was 37 years (23-57 years). The level of amputation was the proximal phalanx in 3 digits and metacarpal in 2 digits. The average procedure time of was 89 ± 12 minutes. The average follow-up duration was 13 months (12-16 months). There was no total or partial digit necrosis in any patient. The mean preoperative shortened DASH score was 52.5 ± 6.7, and the mean postoperative score was 5.3 ± 6.5. The mean preoperative DASH Work Module score was 81.2 ± 18.8 and the mean postoperative score was 13.8 ± 7.5. Two-point discrimination was normal.

CONCLUSIONS

Transfer of the ring finger to reconstruct the amputated thumb is an alternative reconstruction method for patients who do not accept toe-to-thumb and pollicization techniques.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

An ultra-thinned groin flap for reconstruction of complete digital ring avulsion injuries

In complete digital ring avulsions, amputation is usually carried out when replantation of the avulsed tissue is not an option or has failed. The purpose of this study was to report our experience in treating Urbaniak Class III degloved fingers using an ultra-thinned pedicled groin flap. Sixteen patients from ages 11 to 26 years were included. In all cases, the flexor digitorum superficialis tendon, extensor apparatus and proximal interphalangeal joint were intact. Rehabilitation included immediate active mobilization, with flap division at day 21. At a mean follow-up of 15 months, all patients but one were satisfied with the appearance. Two had mild subjective cold intolerance. No flap failure was recorded. The mean total active motion was 183° and the mean QuickDASH score was 8.8/100. Patients recovered S1 sensibility according to the Mackinnon and Dellon classification. The ultra-thinned groin flap has proved to be a reliable technique for non-replantable ring avulsions.Level of evidence: IV.

Cross-finger Flap to the Thumb: Quest for an Alternate Donor

Background  Distal thumb injuries are managed by multiple local and regional flaps. The cross-finger flap (CFF) is one versatile flap used to cover such defects. The donor finger to the thumb is classically described to be the index finger (IF). However, with the index finger being the second most important finger, it causes further debilitation of the already injured hand. Our aim was to find an alternate donor finger to spare the index finger.

Methods and Materials  A prospective observational study was conducted on 10 patients with distal thumb injuries who were admitted between November 2018 and July 2019. Ring finger (RF) was used as donor for CFF in all the cases. The subjects were assessed for first web space angle, Kapandji score, total range of movement (TRM) of long fingers, and global hand function using Michigan hand outcome questionnaire (MHQ) after flap division.

Results  There was no first web contracture and TRM of IF remained unaffected. However, TRM of RF was significantly reduced. But this being a relatively unimportant finger, there was no significant reduction in global hand function, as evaluated by the MHQ score.

Conclusion  The ring finger is a good alternative for index finger as donor for CFF to the thumb, because it provides adequate tissue along with comfortable positioning and easy maintenance of local hygiene. Moreover, it preserves global hand function by sparing the IF.

Ring finger sensorial conduction studies in grading carpal tunnel syndrome: Part II

BACKGROUND

Comparison of sensory conduction of median nerve (MN) with the one of ulnar nerve (UN) over writs-to-ring finger (RF) segment is useful in electrodiagnosis of carpal tunnel syndrome (CTS). However, there is not any consensus regarding the usage of this technique in grading of CTS.

OBJECTIVES

To determine whether the hands of CTS with elicitable MN sensory responses on index finger, but not on RF (non-respondings) compose a more severe electrophysiologic grade than the hands with elicitable responses on both fingers (respondings).

MATERIAL AND METHODS

The patients with bilateral moderate grade of CTS in whom one hand was responding and the contralateral hand was non-responding were included. Conduction study results of MN and UN were compared between respondings and non-respondings.

RESULTS

A total of 19 patients were included. Mean distal sensory onset latency (DSOL) of MN over index finger was longer (4.26 ± 0.49 msec versus 3.44 ± 0.39 msec; p< 0.001), sensory conduction velocity (SCV) was slower (33.7 ± 4.3 m/sec versus 40.2 ± 3.0 m/sec; p< 0.001), SNAP amplitude was smaller (10.3 ± 3.3 μV versus 19.1 ± 7.7 μV; p< 0.001), distal motor latency was longer (5.69 ± 0.60 msec versus 4.63 ± 0.32 msec; p< 0.001), and minimum F wave latency was longer (29.3 ± 1.7 msec versus 26.8 ± 1.4 msec; p< 0.001) in non-respondings than respondings. The nonresponding hand had a longer MN DSOL and slower SCV on index finger compared with contralateral responding hand in all of 19 patients.

CONCLUSION

Non-responding hands have more progressed median neuropathies, and represent a more severe electrophysiologic grade than responding hands. Further studies are warranted to determine whether the absence of MN sensory responses on ring finger is related with forthcoming NCS worsening and a preferable hallmark for deciding surgical intervention or not.

The pedicled groin flap in resurfacing hand burn scar release and other injuries: a five-case series report and review of the literature

XX.

Ring finger sensorial conduction studies in grading carpal tunnel syndrome

BACKGROUND

Comparing the distal sensory latencies of median and ulnar nerve over wrist-to-ring finger (RF) segment is a sensitive conduction parameter in the diagnosis of carpal tunnel syndrome (CTS). However to the best of our knowledge, there is not any research questioning whether the RF studies are useful in grading the CTS or not.

OBJECTIVES

To determine whether the hands with moderate degree CTS and elicitable median nerve sensory responses over second finger and unelicitable responses over RF represent a more severe electrophysiological grade than the hands with elicitable responses over both fingers.

MATERIAL AND METHODS

In patients with clinical diagnosis with CTS, obtained values on sensory and motor nerve conduction studies of median and ulnar nerves were compared between median nerve-to-RF sensorial responders (group 1) and nonresponders (group 2).

RESULTS

Seventy-four recordings belong to 59 patients with moderate degree CTS were included. There were 55 hands in group 1, and 19 in group 2. Mean sensory onset latency of median nerve over second finger was longer (4.17 ± 0.53 msec versus 3.47 ± 0.46 msec; p< 0.001), sensory conduction velocity was slower (34.1 ± 5.5 m/sec versus 40.1 ± 5.3 m/sec; p< 0.001), SNAP amplitude was smaller (7.0 ± 3.3 μ V versus 13.7 ± 6.7 μ V; p< 0.001), and distal motor latency was longer (5.75 ± 0.96 msec versus 4.76 ± 0.42 msec; p< 0.001) in group 2 than in group 1.

CONCLUSION

Median nerve-to-RF sensorial nonresponders have a more progressed compressive neuropathy, and represent a more severe electrophysiological grade than the responders.

Functional conservation between mammalian MGRN1 and plant LOG2 ubiquitin ligases

Plant LOSS OF GDU 2 (LOG2) and Mammalian Mahogunin Ring Finger 1 (MGRN1) proteins are RING-type E3 ligases sharing similarity N-terminal to the RING domain. Deletion of this region disrupts the interaction of LOG2 with the plant membrane protein GLUTAMINE DUMPER1 (GDU1). Phylogenetic analysis identified two clades of LOG2/MGRN1-like proteins in vertebrates and plants. The ability of MGRN1 to functionally replace LOG2 was tested. MGRN1 ubiquitylates GDU1 in vitro and can partially substitute for LOG2 in the plant, partially restoring amino acid resistance to a GDU1-myc over-expression, log2-2 background. Altogether, these results suggest a conserved function for the N-terminal domain in evolution.

A novel method of ring removal from the aging finger

A simple, inexpensive method for removal of a ring from a swollen finger in elderly patients is described. This technique is similar to application of an Esmarch bandage prior to a surgical procedure. The technique uses a sheet rubber blood-drawing tourniquet, a hemostat, and a lubricant. In over 250 cases, this method has failed only once and no complications have been noted.

A SHORT INTERNODES (SHI) family transcription factor gene regulates awn elongation and pistil morphology in barley

The awn, an apical extension from the lemma of the spikelet, plays important roles in seed dispersal, burial, and photosynthesis. Barley typically has long awns, but short-awn variants exist. The short awn 2 (lks2) gene, which produces awns about 50% shorter than normal, is a natural variant that is restricted to Eastern Asia. Positional cloning revealed that Lks2 encodes a SHI-family transcription factor. Allelism tests showed that lks2 is allelic to unbranched style 4 (ubs4) and breviaristatum-d (ari-d), for which the phenotypes are very short awn and sparse stigma hairs. The gene identity was validated by 25 mutant alleles with lesions in the Lks2 gene. Of these, 17 affected either or both conserved regions: the zinc-binding RING-finger motif and the IGGH domain. Lks2 is highly expressed in awns and pistils. Histological observations of longitudinal awn sections showed that the lks2 short-awn phenotype resulted from reduced cell number. Natural variants of lks2 were classified into three types, but all shared a single-nucleotide polymorphism (SNP) that causes a proline-to-leucine change at position 245 in the IGGH domain. All three lks2 natural variants were regarded as weak alleles because their awn and pistil phenotypes are mild compared with those of the 25 mutant alleles. Natural variants of lks2 found in the east of China and the Himalayas had considerably different sequences in the regions flanking the critical SNP, suggesting independent origins. The available results suggest that the lks2 allele might have a selective advantage in the adaptation of barley to high-precipitation areas of Eastern Asia.

ZNRF proteins constitute a family of presynaptic E3 ubiquitin ligases

Protein ubiquitination has been implicated recently in neural development, plasticity, and degeneration. We previously identified ZNRF1/nin283, a protein with a unique, evolutionarily conserved C-terminal domain containing a juxtaposed zinc finger/RING finger combination. Here we describe the identification of a closely related protein, ZNRF2, thus defining a novel family of ZNRF E3 ubiquitin ligases. Both ZNRF1 and ZNRF2 have E3 ubiquitin ligase activity and are highly expressed in the nervous system, particularly during development. In neurons, ZNRF proteins are located in different compartments within the presynaptic terminal: ZNRF1 is associated with synaptic vesicle membranes, whereas ZNRF2 is present in presynaptic plasma membranes. Mutant ZNRF proteins with a disrupted RING finger, a domain necessary for their E3 function, can each inhibit Ca2+-dependent exocytosis in PC12 cells. These data suggest that ZNRF proteins play a role in the establishment and maintenance of neuronal transmission and plasticity via their ubiquitin ligase activity.

The degradation of promyelocytic leukemia and Sp100 proteins by herpes simplex virus 1 is mediated by the ubiquitin-conjugating enzyme UbcH5a

Infected cell protein 0 (ICP0) of herpes simplex virus 1 expresses two E3 ubiquitin (Ub) ligase activities mapping in the domains encoded by exons 2 and 3, respectively. Site 1 (exon 3) is responsible for the degradation of the E2 Ub-conjugating enzyme cdc34 whereas site 2 (exon 2) is associated with a ring finger and has been shown to mediate the degradation of promyelocytic leukemia (PML) and Sp100 proteins and the dispersal of nuclear domain 10 (ND10). In in vitro assays site 2 polyubiquitylates the E2 enzymes UbcH5a and UbcH6 but not other (e.g., UbcH7) enzymes. In this article, we show that ectopic expression of dominant negative UbcH5a carrying the substitution C85A delayed or blocked the degradation of PML and Sp100 and dispersal of ND10 whereas ectopic expression of wild-type UbcH5a or dominant negative UbcH6 and UbcH7 carrying the substitutions C131A and C86A, respectively, had no effect. These results link the degradation of PML and Sp100 and the dispersal of ND10 to the E3 activities of ICP0 associated with the UbcH5a E2 enzyme.

An initial biochemical and cell biological characterization of the mammalian homologue of a central plant developmental switch, COP1

BACKGROUND

Constitutive photomorphogenic 1 (COP1) has been defined as a central regulator of photomorphogenic development in plants, which targets key transcription factors for proteasome-dependent degradation. Although COP1 mammalian homologue has been previously reported, its function and distribution in animal kingdom are not known.

RESULTS

Here we report the characterization of full-length human and mouse COP1 cDNAs and the genomic structures of the COP1 genes from several different species. Mammalian COP1 protein binds to ubiquitinated proteins in vivo and is itself ubiquitinated. Furthermore, mammalian COP1 is predominantly nuclear localized and exists primarily as a complex of over 700 kDa. Through mutagenesis studies, we have defined a leucine-rich nuclear export signal (NES) within the coiled-coil domain of mammalian COP1 and a nuclear localization signal (NLS), which is composed of two clusters of positive-charged amino acids, bridged by the RING finger. Disruption of the RING finger structure abolishes the nuclear import, while deletion of the entire RING finger restores the nuclear import.

CONCLUSIONS

Our data suggest that mammalian COP1, similar to its plant homologue, may play a role in ubiquitination. Mammalian COP1 contains a classic leucine-rich NES and a novel bipartite NLS bridged by a RING finger domain. We propose a working model in which the COP1 RING finger functions as a structural scaffold to bring two clusters of positive-charged residues within spatial proximity to mimic a bipartite NLS. Therefore, in addition to its well-characterized role in ubiquitination, the RING finger domain may also play a structural role in nuclear import.

The Arabidopsis HOS1 gene negatively regulates cold signal transduction and encodes a RING finger protein that displays cold-regulated nucleo--cytoplasmic partitioning

Low temperature is one of the most important environmental stimuli that control gene transcription programs and development in plants. In Arabidopsis thaliana, the HOS1 locus is a key negative regulator of low temperature-responsive gene transcription. The recessive hos1 mutation causes enhanced induction of the CBF transcription factors by low temperature as well as of their downstream cold-responsive genes. The hos1 mutant plants flower early, and this correlates with a low level of Flowering Locus C gene expression. The HOS1 gene was isolated through positional cloning. HOS1 encodes a novel protein with a RING finger motif near the amino terminus. HOS1 is ubiquitously expressed in all plant tissues. HOS1--GFP translational fusion studies reveal that HOS1 protein resides in the cytoplasm at normal growth temperatures. However, in response to low temperature treatments, HOS1 accumulates in the nucleus. Ectopic expression of HOS1 in wild-type plants causes cosuppression of HOS1 expression and mimics the hos1 mutant phenotypes.

The RING finger/B-box factor TAM-1 and a retinoblastoma-like protein LIN-35 modulate context-dependent gene silencing in Caenorhabditis elegans

Context-dependent gene silencing is used by many organisms to stably modulate gene activity for large chromosomal regions. We have used tandem array transgenes as a model substrate in a screen for Caenorhabditis elegans mutants that affect context-dependent gene silencing in somatic tissues. This screen yielded multiple alleles of a previously uncharacterized gene, designated tam-1 (for tandem-array-modifier). Loss-of-function mutations in tam-1 led to a dramatic reduction in the activity of numerous highly repeated transgenes. These effects were apparently context dependent, as nonrepetitive transgenes retained activity in a tam-1 mutant background. In addition to the dramatic alterations in transgene activity, tam-1 mutants showed modest alterations in expression of a subset of endogenous cellular genes. These effects include genetic interactions that place tam-1 into a group called the class B synMuv genes (for a Synthetic Multivulva phenotype); this family plays a negative role in the regulation of RAS pathway activity in C. elegans. Loss-of-function mutants in other members of the class-B synMuv family, including lin-35, which encodes a protein similar to the tumor suppressor Rb, exhibit a hypersilencing in somatic transgenes similar to that of tam-1 mutants. Molecular analysis reveals that tam-1 encodes a broadly expressed nuclear protein with RING finger and B-box motifs.

Cdc53/cullin and the essential Hrt1 RING-H2 subunit of SCF define a ubiquitin ligase module that activates the E2 enzyme Cdc34

SCFCdc4 (Skp1, Cdc53/cullin, F-box protein) defines a family of modular ubiquitin ligases (E3s) that regulate diverse processes including cell cycle, immune response, and development. Mass spectrometric analysis of proteins copurifying with Cdc53 identified the RING-H2 finger protein Hrt1 as a subunit of SCF. Hrt1 shows striking similarity to the Apc11 subunit of anaphase-promoting complex. Conditional inactivation of hrt1(ts) results in stabilization of the SCFCdc4 substrates Sic1 and Cln2 and cell cycle arrest at G1/S. Hrt1 assembles into recombinant SCF complexes and individually binds Cdc4, Cdc53 and Cdc34, but not Skp1. Hrt1 stimulates the E3 activity of recombinant SCF potently and enables the reconstitution of Cln2 ubiquitination by recombinant SCFGrr1. Surprisingly, SCF and the Cdc53/Hrt1 subcomplex activate autoubiquitination of Cdc34 E2 enzyme by a mechanism that does not appear to require a reactive thiol. The highly conserved human HRT1 complements the lethality of hrt1Delta, and human HRT2 binds CUL-1. We conclude that Cdc53/Hrt1 comprise a highly conserved module that serves as the functional core of a broad variety of heteromeric ubiquitin ligases.